Incidental discovery of an abdominal mass is a fairly common occurrence during well-child visits, and while many are benign, pediatricians need efficient paths for identifying serious tumors and assessing an individual’s risk of progression as well as likely treatment response. Pediatric surgeon Willieford Moses, MD, FACS, discusses steps in evaluation, including which imaging modalities are most useful, and describes keys to decision-making for neuroblastoma, hepatoblastoma, renal tumors, germ cell tumors and other tumors seen during childhood. Learn when observation is an option, how experts weigh benefits versus risks on aggressive surgical interventions, and the intra- and post-op risks families should understand.
Hi, everyone. Thank you for the introduction, Maria. Um As mentioned, I'm Willie Moses, one of the pediatric surgeons at the Children's Hospital in Oakland. Uh I primarily practice in Oakland, but as um U CS F faculty, I also spend time in San Francisco and in fact, for many of my surgical oncology patients depending on the complexity. Um there's always considerations even if they're primarily treated in Oakland uh for surgery on the San Francisco side for the availability of adult surgeons. For example, if a vascular surgeon needs to be involved or in some cases with the complex liver tumors, the transplant service. Um nevertheless, I predominantly practice in Oakland. Um and I'm happy to share um the following slide deck as an opportunity to hopefully review some of the common considerations that um you uh all as a community physicians uh and particular pediatricians may have with respect to some of the preoperative questions and laboratory studies and imaging modalities that are frequently used as well as some of the post operative uh challenges that you may see in clinic and thus be the liaison to communicating either myself or sending them back to the hospital for further assessment, should you see or identify a problem? And so please feel free as mentioned to ask questions if you have any. Um you know, while this certainly is by no means exhaustive. Um If there are particular questions beyond this discussion or the slide deck, I'm happy to answer those as well, particularly as it pertains to surgical oncology and again, the pediatric population. Um So, um without further ado uh I have no uh personal or financial disclosures, we'll have her say that I am a father to a two year old. Her name is Flora. Um I, I hate to even show her eating ice cream, but this seemed to be the most recent cute picture I should say of her. Uh That being said, II, I am a father and a surgeon and I check her abdomen almost every time I give her a bath much to the uh incredulous disbelief of my wife uh who likes to comment on it. But nevertheless, um you know, I've been in the emergency department uh and I've taken her there not for abdominal issues, but for G I complaints, I was actually convinced in this picture that she had pyloric stenosis, although that's essentially unheard of in a 12 week old. Uh but as a pediatric surgeon, I couldn't deny the concerns. Uh And so with that, I recognize the challenges faced to many of uh the community physicians when pediatric patients present for well child visits, which is often the most common way, at least that I've identified in which patients present with abdominal masses that are picked up by providers with subsequent um you know, assessments and evaluations completed. And so with that in mind, the objectives here will be to discuss the general differential for an abdominal mass in the pediatric population. Uh some of the cog based or children's oncology group based treatment protocols for common solid organ tumors, uh anticipate the both post operative complications for different types of tumors and and what may need to be done about those. Um and then understand the man principles for a lymphatic leak in particular. And then finally, to describe the post-operative imaging recommendations specifically for germ cell tumors, which I'll, I'll highlight at the end and hopefully give uh enough sort of um feedback or I guess background uh to help um clarify why exactly for many of those patients. It's, it's almost critical that we continue to follow them even though relatively benign tumors, so to speak. So if that abdominal masses, while not particularly common carry a very broad differential in the pediatric population, uh often what guides sort of the um interventions and studies is based upon where it's felt in the abdominal cavity. Uh whether it's a flank uh mass that's appreciated or clearly an inter adominal mass uh or in, in small Children, although often more commonly in some of our adults and populations appreciating a pelvic mass. And what's important is that many of the things on the differential are not uh um tumors, they're not cancer, it's not malignancy. Uh In many instances, it can be a benign cyst that's identified or a cidal cyst or some other pathology that ultimately may require surgery but does not necessarily lead them down the oncologic route. Um In older kids, the differential is a little different than in the neonatal and infant population, but nevertheless, still broad and again, does not always necessarily pretend uh that or concerning, you know, oncologic diagnosis. And so with that said, when these patients present to either the pediatrician's office or even to our emergency department, the most common uh sort of initial steps would be to do imaging. And I I think uh plane film is certainly the most straightforward and easily accessible regardless of where essentially they're presenting to. Um you know, oftentimes particularly if there's concerns that this may be constipation that can very quickly exclude that or rule it in and we can move forward in one direction or another. Uh If there is concerns for an abdominal mass based off of the plane film or physical exam, the next step would be to do an ultrasound. Uh And I say plus or minus Doppler because that does give us more information with respect to the characteristics and the associated vasculature around the tumor, uh but not necessarily critical as a first step because essentially we just wanna confirm that there is in fact a tumor or a solid mass or a cystic lesion. And that can guide the next step, which generally will be cross sectional imaging. The urgency of which is really dependent upon either the symptoms for which they presented to either the pediatrician's office or urgent care uh or with the associated differential and the need for additional image modalities that may benefit from going to the emergency department where we can more easily expedite an MRI as opposed to having to go through the outpatient authorization and approval process. And then again, the possibility that anesthesia may uh complicate the the ability to do that relatively quickly as an outpatient. Uh And so, depending on the differential or the concerns, you know, I I don't think there's ever a hesitation if, if you have one to send the child to the emergency department for further evaluation. Um because oftentimes um even if it's not necessarily an acute presentation, you know, the abdominal mass or complaints that have been present for months, um the ability to expedite uh expedite management and work up is often best facilitated through our emergency department. And not always necessarily the case if it's done as an outpatient, the final caveat, I would say to that particularly with respect to cross sectional imaging, but also true of ultrasounds is depending on where the imaging study is done that can also complicate our ability to either review those images and or have one of our pediatric radiologists here uh at the hospital review the images, particularly if it's an outpatient and the family doesn't readily have access to the imaging studies. And so with that, I would just encourage if you find that your, your patients are getting imaging or are able to get their images relatively quickly uh closer to home. Um Please just in, in an effort to sort of expedite their care, encourage them to actually procure the, the CD or the disk that actually has the images and to bring that with them to clinic so that we can upload it in our system uh for review, either in clinic or or afterwards with our radiologist. So that said, depending on the concerns, you know, there's certainly some basic laboratory studies that all patients should get with respect to CBC and uh B MP uh LFT liver function tests and coags. Uh But then depending on the concerns by ultrasound or where you may feel the mass that should to a degree dictate some of the additional studies that you can get. Um certainly if they come to our emergency department without having had those studies or get admitted, we would, we would do those studies. Uh For example, if it was neuroblastoma, you know, you'd want urinary ST is looking at catecholamines. Uh versus if this was an ovarian tumor, you would be concerned for your germ cell based tumors of which you'd want an A FP and A Beta HCG. And so, uh, the list depending on what the concerns is, can, can, uh, be sometimes extensive. Uh and often, you know, guided by both an emergency department, consult to oncology or consult to the surgery team. So I don't feel that these have to be done as an outpatient. Um, we often do these studies in the emergency department. Uh And so, um, as, uh uh an example, as we get into some of the clinical presentations, um this was a stock photo that um you have online, but essentially this is a three year old who presented to another hospital with dark spots. Um There is um concerns that they had attended local daycare and it hadn't been seen are are noticed uh until later on in the day. And there's thus concerns for potentially non accidental trauma, which uh unfortunately is, is the reality of, of the world we live in with respect to how patients uh occasionally present from uh child abuse and or situations that are obviously less than ideal for them. Unfortunately, though, um while, you know, we absolutely need to go down the the route of non accidental trauma, this can also be a presentation for neuroblastoma as I'm, I'm sure many people are familiar with. Uh And so you, you to a degree have to have a relatively high index of suspicion uh that said for uh neuroblastoma, as I'm sure many are familiar with, it's one of the most common extracranial solid organ tumors in Children. Uh 7% of all childhood cancers, 15% of, unfortunately, all childhood deaths. Uh and remarkably, um although, um we, we speak commonly about neuroblastoma, there's only about 700 cases per year in the United States. With the, uh with the median age of presentation being about two years old. Uh the incidence has increased over time. There are some risk factors that they may point to with associations to maternal factors and some genes that have been implicated as well as some syndromes. But uh unfortunately, we haven't, you know, been able to clearly elucidate. Um why in one patient versus the next? I said they can present in a variety of clinical fashions. Uh Again, the age is generally under five years old with most commonly around the 1 to 2 year old age range. Commonly, it can be an asymptomatic abdominal mass that's appreciated on physical exam. Uh Occasionally, you know, if a child presents with coughing and or some respiratory complaints, uh it can be identified uh on a chest X ray uh as a thoracic based neuroblastoma. Uh and then as well, a pathologic fracture can be a way in which some of these patients present due to the um B and metastatic disease. Uh The clinical signs we look for which are not always present but hypertension Horner syndrome. If it's a thoracic based lesion neurologic symptoms, which certainly are a surgical emergency if there's paraspinal involvement, uh extending into the neural foramina and into the spinal cord. Um, skin lesions, um relatively rare but can be seen particularly in the younger patients with MS disease. Raccoon eyes is the term that they use for the, the bruising if you will around the eyes that um can be mistaken for a non accidental trauma or at least traumatic injury, uh Oxon opticon, myoclonus, um also sort of one of the more commonly discussed signs but relatively rare in terms of presentation, the labs which I sort of alluded to on the prior slides were catecholamines. You can also check a ferritin neuros specific eila and then L DH uh imaging modalities oftentimes the most common study will be AC T scan because that can be done relatively quickly, um does not require anesthesia and it gives us the clinical information to proceed with uh sort of down the algorithm of either treatment or biopsy or intervention. Uh Secondary studies would include a bone scan and then an MIBG study which can both confirm the diagnosis and the presence of metastatic disease. And so when I look as the surgeon at the CT scans or the cross sectional imaging, the most critical thing is to determine the resect ability. Uh and that comes down to a sort of defined set of risk factors if you will, um which are are largely meant to confirm um um uh the presence if you will of uh local regional disease and the potential for uh either catastrophic injury or elevated risks with attempts at surgical resection up front. Uh And so, depending on where the lesion is located, there are certain sort of criteria we look for in terms of vascular encasement um invasion into adjacent um structures or organs or the diaphragm, for example. Um and this sort of guides whether or not surgery upfront can be considered safe or if we need to consider giving, for example, the adjuvant therapy to see if by shrinking the tumor, um we can um knock them down in a level in which it's no longer considered high risk in terms of surgical intervention. So as an example, this would be a thoracic based sort of mediastinal neuroblastoma. Uh And in this case, you can see it's encasing the vasculature coming off of the aorta going towards the left subclavian. Um That would be an image defined risk factor for which to attempt upfront resection would pose significant risk to the vasculature and adjacent structures and potentially depending on how high it extends. Um you know, you can get into the brachial plexus as well. This being an abdominal right adrenal based neuroblastoma. In this case, it appears to be encasing the IVC, which is that arrow there as well as the adjacent vasculature going to, you know, the kidney and the small intestines somewhere in this milieu, you can expect the celiac and the S ma also to likely be encased. And so to consider upfront surgery, you know, is going to put all of those blood vessels at risk and or leaving a significant amount of tumor behind in an effort to avoid injury to those structures. Neither of those would be ideal given the alternative would be to attempt upfront biopsy. And again, we'll get into that briefly, this final picture being left side adrenal based neuroblastoma. Um It appears um that there's no obvious vasculature that appears to be encasing on the superior. You can see a blood vessel, but you'd wanna know to what degree that relationship involves either wrapping around or just abutting the blood vessel because that would guide whether or not it can be resected up front. So, in terms of our staging, we generally follow the international Neuroblastoma risk group or INRG, which um uses essentially the image defined risk factors to define uh L one versus L two tumors. Uh And L two tumors again, when you have wrapping around a blood vessel or invading to adjacent structures, uh most benefit from doing a biopsy and potentially neoadjuvant therapy to get it to shrink down. Um M disease would be metastatic disease and similar to all other unfortunate cancers. Uh And then in particular, you have what's called MS disease, which is essentially in pediatric patients under 18 months in which there's evidence of metastatic disease to the skin, to the bones uh to the liver, um they're in a different category with respect to that metastatic disease than sort of the general patient who has met to, for example, the lungs. Uh And so they have a different treatment algorithm and uh and ultimately, they can have different survival based upon that uh as opposed to the classical, you know, considerations for metastatic disease. And so once you're able to classify based off the initial set of imaging, whether or not this should be L one or L two disease, um you know, depending on the age and then some of the histologic factors that are identified. Um in particular, the min amplification, that's what ultimately will then determine whether or not they're considered very low risk, low risk, intermediate or high risk. Uh and the treatment algorithms in particular, the chemotherapy and the significant regimens that are subsequently required. Um All of which again is um you know, maintained through the children's oncology group is dependent upon how we then classify those patients and, and whether or not they're, for example, low risk versus high risk. Um So the key important things for the risk stratification is the age um generally less than 12 months, but extending up to 18 months, pertains a better prognosis than older patients. Uh amplification uh is certainly bad. And I would say if there's any takeaway nan amplification uh would be considered probably the most significant of the histologic factors for which uh if it's present portends a bad prognosis DNA index and then other sort of favorable unfavorable histology, the mitotic or uh um the MK I, if you will, um all of all of these um are components of the algorithm and the, the treatment plans for these patients in terms of determining both um their risk stratification. And then uh what sort of intervention groups they would be assigned. And so getting back to that third picture, which again showed the image which does not appear to encase the blood vessel, but abuts the blood vessel, which you can see sort of superior this white strip. We consider that essentially an L one tumor. Um it's not invading anything, it's not encasing anything. And so they would be again a candidate for upfront resection. Um depending on the results of the resection, the pathology. Uh again, the critical thing would be to determine, yes, this is neuroblastoma confirmed by pathology, but then whether or not it's m amplified or not. And that will again determine or differentiate whether they, they be considered high risk uh or uh lower intermediate risk. Um I'll give a special note uh to the bottom portion of this slide. Uh because there is in fact, an observation uh algorithm or treatment group uh which is essentially Children under 12 months old who are identified to have an adrenal based neuroblastoma, which is diagnosed either by mibg or urine catecholamines. But nevertheless, if you're able to um identify in a child less than 12 months old and you have imaging confirmation by MIBG or you're in catecholamines. Um There is a, a trial uh that is looking at observation for those patients because it is a high rate of spontaneous regression without any intervention including surgery. We're actually looking at extending that to thoracic based lesions as well. But nevertheless, the critical point here is that uh an option is to just observe those patients if the tumor is less than five centimeters with very frequent surveillance studies, of course, and if there's any evidence that it's brilliant or changing than to consider intervening at a later time point. Um But this is certainly something that is done routinely throughout the US. Um A as an option for the very young, less than 12 month old patients with again, tumors less than five centimeters different than, of course, this tumor, which again, this was that second one we looked at where um you know, this arrow here is pointing to the IVC and you see tumor that's wrapped completely around it. Uh And so that would be considered an L two tumor. And the question becomes, how do we confirm a diagnosis? And the only way to figure out the min amplification status is by biopsy. Uh And so traditionally, that's been an open biopsy, but, you know, I would say more routinely throughout the US and also at U CS F, we're now uh proceeding with uh image guided core needle biopsy, which is done by the interventional radiologists. Uh Historically, the concern has been that it would be inadequate amount of tissue to, to fully evaluate uh the tumor for all of the various studies that are needed to impact. Again, our ability to classify it as low intermediate or high risk. Uh that said with a cod needle biopsy, our invention, radiologists are able to take, you know, 2530 biopsies if necessary uh to, to achieve an adequate amount of tissue, somewhat similar to the one centimeter by one centimeter by one centimeter cube, which is what I would attempt at surgically with an open biopsy. And of course, it minimizes the need for anesthesia and open incision, the recovery from all of that. Uh And so there's good data to suggest that this is a viable option of which again, we, we uh are more routinely doing at U CS F and so for L two tumors, the upfront biopsy is the goal to determine the M in amplification status to classify them as higher intermediate risk. And then depending on that is what determines what the next step in the algorithm would be and to a degree how much of the tumor essentially needs to be removed. Again, if this is a tumor that's completely encased in a lot of critical blood vessels to achieve, you know, a total resection, 100% out is gonna, you know, put that IVC at extensive risk is gonna put the, the contralateral and ipsilateral kidney extensive wrists. You may injure the S MA and now they have no blood flow to the small intestines. All of that um is a consideration for how aggressive you wanna be surgically. And again, if they are making amplification status is negative, if it's non amplified, uh then you may not need to be as aggressive because that's not an as aggressive tumor. Uh And if that favorable histology, 50% might be considered adequate. Um a as opposed to if they're high risk and you really need to be as aggressive as possible in resecting the tumor. So there's a whole treatment algorithm with respect to their induction consolidation phases of their chemotherapy and stem cell transplants is, is certainly beyond the scope of my expertise as a pediatric surgeon. But it's just important to know that within the treatment for neuroblastoma, there is a very extensive algorithm that I'm sure unfortunately many of your patients uh have had to undergo which can last, you know, you know, certainly more than a year in terms of their treatments with surgery, just being one component and the timing of that surgery within uh the the cycles of chemotherapy and, and with respect to when a transplant is done, uh can be variable. But um you know, largely it's just important to recognize that surgery is just one component uh of their multidisciplinary care for many of these patients, particularly with high risk treatment protocols. Uh MS tumors, again, these are the patients less than 18 months old with skin liver bone disease. Um you know, you again, wanna figure out their making amplification status and then determine similar to the L two tumors. What degree local regional control with surgery can be achieved. Metastatic tumors. Uh very similar depending upon the making and amplification status will determine how aggressive we need to be surgically to manage the primary site. But again, in the setting of metastatic disease, as we all know, um you know, uh surgery at the primary site does not necessarily treat the additional or it does not treat the additional sites. And so it's just one component of uh sort of multi modal approach. So surgery for neuroblastoma, I'll put up two pictures mainly just so you guys can appreciate the, the challenge if you will um when these tumors wrap around the blood vessels. Unfortunately, because of the location in the back of the abdominal cavity for the adrenal based tumors, those blood vessels are the celiac which supplies blood flow to the liver, uh as well as the spleen and the pancreas. Um and the uh S ma superior Mesenteric artery which supplies the blood flow to the small intestines. Uh And when the tumor is completely wrapped around it to be very, very aggressive, which historically, in the past, at least I would say was always the goal for these patients. Um You put them at considerable risk if you injure the S MA, and now they have no blood flow to obviously the small intestines. Uh and so, as a result, we've attempted to identify, you know, uh 95% for example, resection as a goal to account for leaving small bits of tumor around the blood vessel, which can still classify as you know, successful surgery. Certainly, if you've avoided injury to uh some of these critical structures and as well, particularly with mediastinal tumors. But just as an example, um there's all the additional structures that these tumors can encase when you're in the mediastinum resecting tumors. Unfortunately, you have the art of a Danski Wiz uh and that supplies, you know, it's responsible for spinal perfusion. And so you can attempt 100% resection and may be successful in that. But unfortunately, you've compromised blood flow to the spinal cord. And as a result, the patient now has neurologic symptoms and deficits in their lower extremities. And so it's critical to obviously know the anatomy, but also define the goals of surgical approach because unfortunately, to attempt 100% resection can compromise some of these critical structures. And in particular, when these patients are already receiving a very intensive multimodal approach to their treatment, you know, attempting to get 100% out surgery uh surgically, that may in fact be deleterious to the overall outcome. So, um to get into some of the post-operative management um you know, speak example, post-operative day six. After a section of a left sided adrenal based neuroblastoma, the patient had been doing well, got discharged home presents to the pediatrician's office day after discharge with increased abdominal distention and discomfort. And so, um you know, if this child was sent to the emergency department and or through a pediatrician, the next step likely would be to do an ultrasound, which may show a moderate amount of ascites. There's always a concern is, is this blood, for example. Um but the biggest concern that would run through my mind is is if this is lymphatic fluid that is built up. And so kyla societies, lymphatic fluid in the abdominal cavity. Um unfortunately, and which is often not necessarily appreciated beforehand, uh carries a 20% risk with neuroblastoma resections. Um And the majority of these patients are managed completely non operatively in many instances and may not even be identified because it resolves on its own without ever developing abdominal distension or discomfort. But I I always uh cite this to families up to 20% of patients may require additional interventions, whether that uh is being NPO with TPN uh or prolonged hospitalizations with peritoneal drains. Um you know, it certainly, um you know, correlates to the extensiveness of the resection and where the tumor located with respect to the lymphatics and, and structures that may be compromised during the resection. Uh But nevertheless, 20% may unfortunately require some further intervention to manage a lymphatic leak. And so I would consider that to be uh relatively common with respect to the post operative complications that we see to briefly get into the path of physiology. Um you know, the um uh when fat is absorbed in the gut, um it um has two differentiated pathways essentially for long chain fatty acids that actually gets absorbed through Chylomicron. Those Chylomicron go through the lymphatic structures in the back of the abdominal cavity to the cistern and Kyle, then to the thoracic duct and then to the subclavian vein that being the normal pathway for the majority of the fat that we intake. However, medium chain triglycerides get absorbed directly from the intestines into the portal venous system and go straight to the liver for breakdown. And so I I mentioned this because our treatment for lymphatic leaks is essentially based upon this um for tumors in which we are doing extensive dissections, essentially, you're compromising that lymphatic flow. And thus, when we have Kyle leaks, it's because you've disrupted uh the normal pathway for in particular long chain fatty acids and Chylomicron to be absorbed back into the system. And so our treatment essentially is to try to cut out the um the nus for ongoing lymphatic leaks by decreasing uh the intake of fatty acids and in particular long chain fatty acids. And so as many of you may unfortunately see, uh in some of our patients, it they get discharged on a medium chain triglyceride formula. Um you know, it's often because we're trying to select for medium chain triglycerides, which do not get absorbed through the lymphatics, but actually get absorbed directly into uh the portal venous system and going straight to the liver. And so there's different algorithms that some, some hospitals will use in treatment, you know, approaches. But essentially the long and the short is to attempt a low fat diet. And one focused on medium chain triglycerides if that fails, and there's still abdominal distension or fluid plus or minus of drain that may be placed, uh then they can be placed on octreotide or satin. And unfortunately, if there's no response to that, then they can be completely NPO with TPN. Uh and in the vast majority of patients that's sufficient, albeit maybe for a prolonged period of time, but does not require further surgical intervention uh if they fail to resolve with that. However, then there's considerations for doing lympho syt gray. And our interventional radiologist can attempt uh to embolize the small lymphatics if they're able to identify them. Uh or unfortunately, some patients may ultimately require surgery, but I would say that's very rare. Often, the majority of these patients can be managed non operatively with dietary modifications. Other complications from neuroblastoma, certainly intraoperatively, there's vascular injury, injury to the kidney and the blood vessels to the kidney adrenal gland, which again is the majority of our intraabdominal neuroblastoma, uh sits right on top of and shares blood flow with the kidney. And so, uh unfortunately, the the kidney is often at risk particularly the blood vessels to the kidney. During these uh sometimes challenging dissections postoperatively. As mentioned, there can be ky leaks chylothorax or Kylo Society's Corner syndrome when we're operating in poster metal tumors in the chest and upper thoracic cavity. Unfortunately, you have risk for potential nerve injury and subsequent corner syndrome. Uh just lastly on the subject of neuroblastoma. Uh it's important to recognize that, you know, for stage one disease for the favorable histology, nan non amplified, low risk groups, they actually have a fairly high overall survival, much different in our stage four patient populations. And so um important to recognize neuroblastoma is just part of uh a, a group of neuroblast tumors. This being an example of a ganglioneuroma. So this was a patient uh that I had taken care of with the large abdominal mass. It was appreciated by the pediatrician during the well child visit. As you can see in these pictures, it's basically compressing. Um you know, many of the important blood vessels, this being, you know, the um S ma right here, the renal, you know, it's clearly um in uh touching upon many blood vessels. And so to immediately jump into the operating room, um would be high risk for this patient. And so we proceeded with a biopsy that biopsy showed as a ganglia neuroma. Uh And so, um you know, it would have been ideal to leave it at that. Unfortunately, with ganglia neuromas and it's just a small sample of the tumor, there can be other areas within that large tumor that uh arbor neuroplastic components, uh neuroblastoma, for example. Uh And so it's very difficult to, to hang our hats with it being ganglioneuroma, but important to recognize that ganglioneuroma carries a very favorable prognosis. Whereas ganglia neuroblastoma, particularly the nodular subtype or frankly neuroblastoma, a much more aggressive variant on the spectrum of neuroplastic tumors. Uh And so there are certainly some characteristics that we look for and there's different treatment algorithms if we can feel confident that this is just a neuroblastoma, excuse me, a gangland neuroma. Some people actually advocate for just simply treating it with uh observation to see if it grows. And there are many people in which this can be identified as a tumor in the 30 or forties. And the presumption being it's been there for a very long time and thus, maybe they don't need any surgery at all. If we can feel confident it's ganglia neuroma very different than however, if there's a neuroplastic component or element to the tumor. Uh And so the study that I was just pointing to which this is sort of their, their uh 53 patients to show that, you know, for the three patients in the ganglia neuroma uh side that were managed with observation none of them ultimately succumbed to their disease nor had progression of disease. So, observation is an option for ganglioneuroma very different. However, if it's ganglial neuroblastoma or obviously, neuroblastoma, and as one can surmise the outcomes are variable based upon in terms of survival. Uh if it's gangl blastoma intermixed versus the nodular subtype versus frank neuroblastoma with, of course, and unfortunately, the worst of the survival. So just to summarize um because we, we will be moving on from neuroblastoma. Uh it's the most common pediatric extracranial solid tumor. Um image defined risk factors are what guide whether or not surgery upfront is an option or if we need to do chemotherapy. Um The risk stratification is largely based upon the Mick in status but also other components of the biology and histology. Uh Overall, the treatment is guided by protocols from cog uh and neuroplastic tumors comprise uh a couple of benign variants, uh Gangel and then gangs or ganglioneuroma intermix subtype. And so with, with that, quite a bit of information, just wanna give a pause if there are any questions um for moving forward. And Maria, you can just uh interrupt me if there were any questions that were placed at in a chat or not. Yeah, I haven't seen it yet. OK, I'll, I'll jump in if something comes up. No problem. Well, um we will uh proceed then. So um next is a two year old who presented to um pediatrician after a grandmother had felt a mass during bath time, which is very common, not necessarily grandma, but just someone feeling an abdominal mass while they're bathing the child and an ultrasound confirmed a liver mass. And the pediatrician appropriately ordered uh a FP level which was elevated at 61,000, certainly elevated for a two year old. And so pediatric liver tumors. Um, you know, the um most common, uh and certainly the, the one that carries the most common pediatric concern would be hepatoblastoma. But it's important to recognize that there is a broad differential and that it's not always hepatoblastoma, particularly as you move beyond the infancy and the toddler age Children uh to a school age and adolescence, it's unfortunately more common to see, you know, a pato cellular carcinoma uh or sarcomas. Um there of course, are the benign uh findings that we can see particularly in adolescents and teenagers, for example, the FNH or um pic adenoma. And so, um this just to give a little more in terms of the, the, you know, frequency of it for hepatic tumors. This was a study um from a pathologist down in, in Los Angeles and of the 285 tumors in patients under two years old, 43% were hepatoblastoma. But very quickly you get into a broad differential of other potential findings. And of course, the interventions vary dependent upon that hepatic tumors in older Children, hepatocellular carcinoma. The most common one that we're concerned about. But FNH also being AAA relatively frequent finding for these patients to focus on hepatoblastoma because that again is the most frequent thing particularly that, that we'll we'll deal with for our patients. Um How we define our interventions for hepatoblastoma are largely dependent upon where it's located with underlying histology is uh and the potential prognosis as a result. And so, um when we think anatomically or at least when I do as a surgeon, it's largely dependent upon the hepatic veins. So, an important point here is that the hepatic veins define the sections of the liver and where the tumor is, is within the liver with respect to the hepatic veins, guides both the extent of a potential resection, but also the feasibility of a resection for the patient. And so if um if you, you keep that in mind, when we think about liver tumors, it's actually um you know what we call the pretext criteria, which we use to guide the classification of the hepatoblastoma. So pretext, one, for example, is when you have a tumor that's isolated to one section of the liver with three contiguous sections that are tumor free. So if you see there's tumor here and the right section here, you have three contiguous sections. Again, these sections are defined by our hepatic veins. There's the right hepatic vein, middle hepatic vein, left hepatic vein lateral to the right hepatic vein is one section between the right hepatic vein and the middle hepatic vein is the second section. A third one being between the middle and the left and then lateral to the left is where you find the fourth section. So when you have a tumor combined to one of the lateral portions, either on the right side or the left side, there's three contiguous sections without tumor. And so that's a pretext. One for which upfront surgery would be an option. There's pretext, two, pretext three and then pretext four. And based upon where the tumor is or how many tumors there is, what defines whether or not it's considered, you know, up amenable to upfront resection or not. And then similar to our image defined risk factors. There are annotation factors within how we interpret the imaging for liver tumors that guide the, the safety and feasibility of a resection. It may be a pretext too confined to one side of the liver. But if it completely abuts the the middle hepatic vein in order to get a negative margin, unfortunately, the extent of your surgery now may need to be extended as a result. And so, um um just briefly, um generally, the cog recommends upfront resection for what we consider very low risk, um which is a pretext, one or two with uh with um pathology demonstrating what we call pure fetal histology. Uh they can be managed with the surgery alone and no other intervention required if surgery is successful. And negative margins. Um You know, if there's concerns that uh the tumor abuts or comes close to the middle hepatic vein, uh as mentioned, unfortunately, that means that, you know, upfront surgery may not be an option and you wanna give them chemotherapy, which the primary uh chemotherapy regimens are cis-platinum based or platinum based regimens. Um I won't get too much into this but just know that depending upon the low intermediate or high risk will determine to what degree and extent they will require chemotherapy. And all of this is currently being studied within cog protocols. And there's active studies for which we attempt to enroll of our patients to further sort of guide our our future interventions with respect to liver um complications. Um As as one can imagine, these are, are, you know, very challenging operations because of the extensive degree of blood flow to the liver. Um Unfortunately, there are complications that are often identified at the time of surgery immediately postoperatively, but occasionally, um when they present to the pediatrician if they have follow up within days after surgery. And so bleeding hematoma bile leaks, um you know, for the extensive resections, there can be hepatic insufficiency, meaning, you know, it appeared, you know, removing three quarters of the liver would still leave an adequate amount of liver for, for the child. Unfortunately, that is not always the case. And so if they don't have adequate function, um that obviously is a big problem Um that is why, unfortunately, for particularly, you know, pretext for tumors where there's extensive involvement throughout the liver. Um transplant is in fact the best treatment option and not resection um portal vein thrombosis. Um Certainly a consideration when we're, we're operating next to critical blood vessels and there can be thermal injury. Um So, uh the next patient, this is a two year old, again presented to the pediatrician with concerns for constipation, uh subsequently developed nausea, vomiting. The previous plan had been a referral to G I. But with the nausea, vomiting, there was concerns that, you know, this increasing abdominal distension growth and now mass were more concerning. And so it was sensitive ed for further work up where AC T scan revealed this very large left sided tumor. Um And so in two year old, left side tumor concerns based on imaging for renal tumor if that's essentially wils until proven otherwise, um renal tumors, relatively rare. 6.3% of the cancers found in Children less than 15. However, the majority of those particularly in in the excuse me, toddler age range are gonna be a Wilms tumor. Um Fortunately, their survival for Wilms tumor is very, very high. Uh and particularly in for low stage uh groups. It can be, you know, approaching 100%. Median age of diagnosis is 2.5. Uh most often it is unilateral uh tumor, but it can be bilateral, particularly if there's associated syndromes or underlying genetic predispositions. Uh that changes how we manage it. Of course, because you, you can't do bilateral nephrectomies and have successful outcomes. Um, risk factors. Um you know, these, you know, questionable um maternal exposures, um low birth weight and preterm babies. Um A again, um there's genetic predispositions as well and syndromes uh that increase the likelihood and in some patients, they'll be actually screened routinely for Wilms tumors as well as uh hepatoblastoma depending upon the genetic predisposition. Clinical presentations, most often these babies are asymptomatic, but they can present with hematuria, hypertension, varicocele scene on physical exam. Um Children with horseshoe kidneys are at a higher risk of Wilms tumor. So they need to be monitored for it. The work up generally starts with an ultrasound and in particular, if you find yourself ordering an ultrasound, it's helpful to have a Doppler, although we would certainly repeat it as soon as the patient arrives here in Oakland. But what we're looking for is evidence of um vascular invasion and tumor thrombus is that uh pertains a different prognosis and certainly impacts from a surgical standpoint. Are our options for resection CT scan or MRI you know, again, it's variable which, which image modality. Often we go with AC T scan because of expedited nature of it. Uh and then AC T scan of the chest look for evidence of metastatic disease. The goal of surgery is to essentially remove the tumor without spillage, the critical thing with spillage if you get into, uh the actual tumor is unfortunately that it, it takes what may be a low risk tumor and upstages them, which changes their chemotherapy and their radiation protocol. Um And because they're at certainly higher risk for, you know, regional recurrence, uh we attempt to sample the lymph nodes, in fact, not sampling enough lymph nodes is one of the most common, you know, errors made from a surgical standpoint. Uh because if you don't have an adequate number of lymph nodes sample, then unfortunately, you can't properly stage them. And in some instances, they may require a more aggressive chemotherapy because we, we don't necessarily know. Um Yeah. Um I think that's what I wanted to say there. Um in terms of primary surgery upfront, you know, if, if there's concerns that there's vascular invasion, in particular, if there's tumor thrombus, that goes into the renal vein and then the IVC and then extends up towards the heart, that would be a contraindication to upfront surgery. And you'd wanna give chemotherapy first if there's concerns that there's an involvement in medicinal structures, the spleen the liver, the pancreas, uh chemotherapy upfront. If there's bilateral tumors, you wanna try to shrink them with chemotherapy and then consider uh doing the nephron sparing approach, partial nephrectomies essentially. And then if there's pulmonary compromise, now, if there's, you know, a single solitary pulmonary lesion, you would still wanna approach uh for local regional control a nephrectomy. Uh But if there's diffuse metastatic disease and respiratory compromise as a result, whether that potentially is for metastatic disease or uh or thrombus, which can be tumor thrombus. And further evidence of metastatic disease upfront chemotherapy may be the best option. Um Just briefly, there are certain groups that would not require any chemotherapy postoperatively, that's in particular stage, one favorable histology. So Children less than two years old with relatively small tumors, surgery alone may be curative for them uh complications and I have a few more slides. So we'll move a little more quickly. But uh essentially there's interoperate complications. Uh, tumor spillage uh is a significant one because it changes uh both their prognosis and the additional therapies required, uh bleeding and vascular injury, you know, certainly things that are identified readily and, and have to be managed in the operating room post operatively. And I wanna highlight in a deception because when we do these retroperitoneal dissections, there's a thought that there may be disruption of some of the um um some of the sympathetic um nerves to the small intestines and potentially uh a disruption in the normal peristaltic movements of the intestines which increase the propensity for in a su exception. Uh And so if you have a child with colicky type pain, you know, a couple weeks, a month or two after surgery, um, you know, it would be important to send them for an ultrasound or to the hospital to evaluate both for a potential bowel obstruction but also for potentially in a se section. Um because that is more common in these patient populations. So, um there may be a question, why don't we all those? I have a couple more um slides. Uh So, um so this is a 12 year old who presented for clearance, preoperative or pres sport clearance, essentially, which I think is probably a common scenario. Um Of note, when they presented, there was abdominal fullness of which the the parents had commented I've been there for a few months. And again, this was thought to be potentially constipation. It was until the pediatrician evaluated that it was very clear that there was a mass there. And so they sent this patient for further evaluation and got AC T scan. And what you can see on the CT scan is there's a very large tumor appears to be emanating from somewhere in the pelvis. Uh This is the uterus here and this may be the right ovary unclear. Uh But you can see this large tumor has different densities here. So solid mass, this looks like fat density. Then on this next side, this would be calcification. And so when you see fat, solid tumor and calcification that should particularly in a female patient, raise concerns for a teratoma of likely ovarian origin, which unfortunately, this was uh the further work up if that's the concern would be to send tumor markers, the typical ovarian tumor markers that we want uh are uh serum beta HCG and A FPL DH C A 125 and an inhibit A AND B. And if those aren't sent um as an outpatient, we send them from uh the emergency department, we always wanna send them before any resection. Uh because knowing the preoperative levels will allow us to monitor potentially postoperatively for evidence of recurrence if you don't know preoperatively what it was and it's negative or, or within normal limits, postoperatively. Uh Unfortunately, you'll never know if it was elevated beforehand. And thus, you know, you're, you're in the sort of liminal space with respect to whether or not to follow it afterwards. This was that patient's tumor. It was about 17 centimeters consistent with a mature teratoma. Um briefly, ovarian tumors, I would say relatively common with respect to the pelvic tumors that we see in our pediatric patients. Germ cell tumors account for the overwhelming majority of these neoplasms in, in pediatric patients different than the adult population in which they're more epithelial based. The typical concerns for aggressive cancer and a and a 70 year old patient uh would be an epithelial tumor. Very rare for them to have a germ cell tumor at that age. Uh The most common germ cell tumor we see is a mature teratoma which is a relatively benign tumor for which surgery upfront with complete resection is considered curative. Essentially, it's important to know. However, that these patients have a high risk of recurrence. Both. Um because we attempt to, you know, do an ovarian sparing approach, meaning just take the tumor out to preserve the, the ovary. But also because they have a, a high risk of a contralateral either synchronous or metachronous tumor in the other ovary. And so, one of the mainstays of treatments for germ cell tumors is to attempt an ovarian sparing operation because we know they're at a high risk for getting a tumor in the other side. And if you do an upfront oophorectomy for one side, and then five years later, they develop a tumor on the other side, there's no telling whether or not at that point you'll, it'll be amenable to an ovarian sparing approach. And unfortunately, if you've already removed one ovary, obviously, 11 can deduce um the concerns with respect to fertility and as well hormones for, for that patient. If you now have to contemplate uh uh oophorectomy on the contralateral side, the staging based upon whether the tumor is confined or there's evidence of either metastatic disease or fluid that's sampled. If there's tumor cells in the site that's picked up, that then determines if these patients would require chemotherapy, of which the majority are gonna be a stage one tumor and not require chemotherapy, overall survival very high for these patients. Uh postoperatively. And again, you know, if we had tumor markers, we wanna follow those uh and important for I think the pediatricians to recognize is that for these germ cell tumors, we wanna do surveillance imaging and this is critical because of that risk to the contralateral side as well as if we were successful in an ovarian sparing approach, meaning just removing the tumor and leaving the ovarian place. We want to look for any evidence of recurrence there and that generally will extend for up to five years if not longer in terms of their surveillance protocols. This last patient, which I'll just show is, is a picture of the patient who presented with acute onset of abdominal pain uh for which there is concerns for ovarian torsion. Certainly, if there's a large ovarian mass or lesion and severe abdominal pain that always rises to the top of the differential, our goal is to try to preserve the ovary because even if in the operating room, it looks dark or black, oftentimes it can remain viable. And so um we'll attempt as much as possible to det to it and leave it in place without resection. Important though, to note is if we're successful in that and it regains viability, there are some reports that 50 to 58% of these patients can have an underlying mass. And so, in addition to, you know, surveillance to confirm viability of these uh ovaries, we also wanna confirm that, you know, 6 to 8 weeks later, uh when we get an ultrasound, you know, we don't see a tumor that was responsible for that torsion. It's commonly gonna be because of a large cyst, a follicular cyst that developed. And once it gets over five centimeters, there's a higher risk of it tors, but occasionally it can be, uh, because there's an underlying mass and we wanna identify that because at the time when we det tose it, you're not able to assess the entire ovary may look black, it may appear black. That's consistent with what it could look like if there was a hemorrhagic cyst that led to the torsion. And, and because it's now filled with potentially hematoma, you can't assess for underlying mass, which again is why postoperatively, even if we were successful in preserving that kid that ovary and it's viable, we wanna confirm that there's no evidence of metastatic disease or excuse me, not metastatic disease, but an underlying tumor. And so with that, that was very long winded and quite a bit of information. But just to briefly summarize abdominal masses are common. They carry a very broad differential in the pediatric population of which cancer and tumors is unfortunately, fortunately a relatively small component, but still something to consider, particularly since the majority of those patients will present with an asymptomatic mass. Ultrasounds are generally considered the first step because it's relatively straightforward, can be done typically close to home and can give us a lot of important clinical information to guide the next step. Lymphatic leaks are something that we commonly see after resections of tumors in the retroperitoneum, neuroblastoma, Wilms tumors, large liver tumors, uh and those are often managed with simple dietary modification and don't require surgery then finally mature teratoma, which we commonly see as the germ cell tumor uh in our adolescent patients, um carries a very favorable prognosis, but it's important to follow these patients for any evidence of recurrence and or uh contralateral disease. And so, um that was my last slide. Um.
