Hepatoblastoma with Dr. Greg Tiao

Published: 2022-02-03

23 Views

0 Likes

0 Shares

0 Comments

Grand Rounds

View profile →

Inside this episode

Kai, the Library's AI content creator, listened to this episode and mapped who's speaking, the chapters, key claims, and cases. Every item links to the exact moment in the recording.

AI-enriched

Who's speaking

Speaker 1 — host
Dr. Greg Tiao — guest
Speaker 3 — host
Speaker 4

Chapters

0:00Introduction and Differential Diagnosis — Overview of hepatoblastoma epidemiology and differential diagnosis for pediatric abdominal masses, including neuroblastoma, Wilms tumor, hemangioma, and other liver lesions.
2:08Clinical Presentation and Diagnostic Workup — Discussion of hepatoblastoma presentations ranging from asymptomatic mass to tumor rupture, the role of AFP in diagnosis, and the four essential diagnostic components: history, imaging, AFP, and liver biopsy.
4:00Liver Anatomy and PRETEXT Staging — Detailed review of liver segmental anatomy (Couinaud classification), anatomic landmarks on imaging, and the PRETEXT staging system based on number of contiguous liver sections free of tumor.
6:34Treatment Algorithms and Transplantation — Treatment strategies based on PRETEXT stage, including primary resection for PRETEXT 1-2, neoadjuvant chemotherapy for PRETEXT 3-4, indications for liver transplantation, and the importance of early transplant center referral.
8:46Current Research and Conclusion — Overview of the ongoing Pediatric Hepatic International Tumor Trial (FIT study) aimed at refining risk stratification and treatment algorithms for hepatoblastoma.

Key claims

0:00Hepatoblastoma is the most common malignant liver tumor in the pediatric population — Speaker 1
0:15There are around 250 new cases of hepatoblastoma per year — Dr. Greg Tiao
0:15Treatment algorithms for hepatoblastoma have changed dramatically over the last 20-25 years — Dr. Greg Tiao
0:51Neuroblastoma is considered by most to be the most common abdominal wall malignancy in children — Dr. Greg Tiao
1:13Neuroblastoma is the most common solid malignancy in the pediatric population — Speaker 3
1:28The differential diagnosis for liver tumors includes hepatoblastoma, hemangioma, hematomas, focal nodular hyperplasia, and hepatocellular carcinoma — Speaker 3
1:41Hemangioma is the most common liver lesion in children — Dr. Greg Tiao
2:08Hepatoblastoma can present as an asymptomatic abdominal mass, tumor rupture, respiratory distress due to tumor size, or as a paraneoplastic syndrome like precocious puberty — Speaker 3
2:08An elevated alpha-fetoprotein (AFP) is a key component in the workup of hepatoblastoma — Speaker 3
2:08AFP is critical for the diagnostic algorithm and is a guide for treatment response — Speaker 3
2:39MRI is used by most experts to delineate anatomy and evaluate the extent of liver involvement in hepatoblastoma — Speaker 3
3:00EOVIST is an MRI contrast agent that is taken up by hepatocytes and then excreted, providing the best definition when looking at the liver on imaging — Dr. Greg Tiao
3:17To establish a diagnosis of hepatoblastoma, four things are needed: history, abdominal imaging, AFP check, and liver biopsy — Speaker 3
3:17The most important intervention for survival in hepatoblastoma is to achieve complete resection — Speaker 3
3:17Aggressive resections for hepatoblastoma include trisectionectomy, mesohepatectomy, resection with an additional procedure in the remnant liver, and liver transplantation — Speaker 3
4:08Couinaud labeled liver segments in a counterclockwise fashion after the districts of Paris by injecting portal vessels — Dr. Greg Tiao
4:45The right hepatic vein differentiates anterior sections (5 and 8) from posterior sections (6 and 7) of the right liver — Dr. Greg Tiao
5:20The right portal vein separates superior segments (7 and 8) from inferior segments (5 and 6) of the right liver — Dr. Greg Tiao
5:53The PRETEXT staging system classifies tumors based on the number of contiguous liver sections free of disease, calculated as 4 minus the number of free sections — Speaker 3
6:34PRETEXT 1 has 3 contiguous sections free of disease, PRETEXT 2 has 2 contiguous sections free, PRETEXT 3 has 1 free section, and PRETEXT 4 has no free sections or diffuse tumor burden — Speaker 3
6:34PRETEXT 1 and 2 tumors with greater than a centimeter margin from the middle hepatic vein and portal bifurcation should be considered for resection at diagnosis — Speaker 3
7:15The change in practice for PRETEXT 3 and 4 tumors improved survival rates for hepatoblastoma from less than 30% in the 1970s and 1980s to between 80 and 90% today — Dr. Greg Tiao
7:31PRETEXT 3 tumors are generally biopsied at diagnosis and then started on neoadjuvant chemotherapy — Dr. Greg Tiao
7:31Indications for liver transplantation in hepatoblastoma include unresectable disease, unsafe to resect, or resection would leave inadequate liver remnant — Dr. Greg Tiao
8:11It is important to consult a transplant center early for PRETEXT 3 or 4 liver disease — Speaker 3
8:19Teams are now trained to recognize tumors and send them to centers that offer transplant or can do aggressive resection — Dr. Greg Tiao
8:46The Pediatric Hepatic International Tumor Trial (FIT) is an ongoing multinational trial aimed at better delineating treatment algorithms and identifying high and low risk features for each PRETEXT stage — Speaker 3
9:06The FIT study has been ongoing for three years — Dr. Greg Tiao

Points of disagreement

0:51Most common abdominal malignancy in children
- Dr. Greg Tiao: Most would consider neuroblastoma to be the most common abdominal wall malignancy in children, though this is somewhat controversial
- Speaker 3: It's a toss up between neuroblastoma and Wilms tumor depending on who you talk to; you could make an argument that Wilms is the most common abdominal malignancy since neuroblastoma tumors occur throughout the body

This episode was analyzed and enriched by Kai, the Library's AI content creator. Every item links to the moment it comes from — click a timestamp to listen in context.

Written for:

Hepatoblastoma: From Recognition to Resection Strategy

The episode's teaching points arranged as a structured lesson, building from the basics up to the finer points. Written by Kai from the episode transcript and reviewed before publishing.

For trainees · Teaching arc · AI-written, human-reviewed

Foundation: Differential and Diagnostic Essentials

Hemangioma is the most common liver lesion in children, not hepatoblastoma. With only 250 hepatoblastoma cases annually, maintaining a broad differential is critical when a child presents with a liver mass 0:15 1:41. The workup requires four components: history, abdominal imaging (MRI with EOVIST contrast preferred), AFP level, and liver biopsy 3:17. AFP serves dual purposes — it anchors the diagnosis and tracks treatment response 2:08. EOVIST, an MRI contrast agent taken up and excreted by hepatocytes, provides superior anatomic definition for surgical planning 3:00.

Anatomic Literacy: The Couinaud System in Practice

The right hepatic vein separates anterior from posterior sections; the right portal vein separates superior from inferior segments. Couinaud numbered liver segments counterclockwise (after Paris districts) by injecting portal vessels 4:08. On the right side, segments 5 and 8 lie anterior to the right hepatic vein, while 6 and 7 lie posterior 4:45. The right portal vein divides superior segments (7 and 8) from inferior segments (5 and 6) 5:20. This anatomic framework is not academic — it determines resectability and drives the PRETEXT staging that governs treatment.

The PRETEXT System: Staging That Dictates Strategy

PRETEXT stage equals 4 minus the number of contiguous tumor-free sections. The liver divides into four sections: right posterior (segments 6-7), right anterior (5-8), left medial (4), and left lateral (2-3) 5:53. PRETEXT 1 tumors have three free sections, PRETEXT 2 have two, PRETEXT 3 have one, and PRETEXT 4 have none or diffuse involvement 6:34. PRETEXT 1 and 2 tumors with greater than one centimeter margin from the middle hepatic vein and portal bifurcation should be considered for upfront resection 6:34. This is the straightforward group.

The Game-Changer: Neoadjuvant Therapy for Advanced Disease

PRETEXT 3 and 4 management transformed hepatoblastoma survival from under 30% to 80-90%. This single shift — biopsying PRETEXT 3 tumors at diagnosis and starting neoadjuvant chemotherapy rather than attempting immediate resection — accounts for the dramatic improvement in outcomes over the past 20-25 years 7:15 7:31. The strategy recognizes that complete resection remains the most important intervention for survival, but achieving it may require downsizing the tumor first 3:17. For PRETEXT 3 and 4 disease, aggressive resections include trisectionectomy, mesohepatectomy, resection with additional procedures in the remnant liver, and liver transplantation 3:17.

Early Transplant Consultation: A Non-Negotiable

Consult a transplant center early for PRETEXT 3 or 4 disease — the earlier the better. Indications for transplantation include unresectable disease, unsafe resection, or inadequate projected liver remnant 7:31 8:11. Teams now recognize these tumors earlier and refer to centers offering transplant or aggressive resection expertise 8:19. This referral pattern change is as important as the chemotherapy itself — it ensures patients reach centers capable of the full range of interventions before treatment decisions narrow the options.

The Current Frontier: Risk Stratification Within Stages

The ongoing Pediatric Hepatic International Tumor Trial (PHITT) aims to identify high and low risk features within each PRETEXT stage. Three years into enrollment, this multinational trial seeks to refine treatment algorithms by recognizing that not all PRETEXT 3 tumors behave identically 8:46 9:06. The goal is precision — matching treatment intensity to tumor biology rather than anatomy alone. For the trainee, the lesson is that today's staging system, transformative as it has been, remains a work in progress. The judgment to escalate or de-escalate therapy will increasingly depend on molecular and histologic features layered onto anatomic staging.

The discussants emphasized that the survival gains in hepatoblastoma came not from a single breakthrough but from systematic changes: earlier recognition, neoadjuvant chemotherapy for advanced disease, willingness to perform aggressive resections or transplant, and centralization of care to expert centers 7:15 8:19. Each element required abandoning prior assumptions about what was resectable or survivable.

Takeaways from this story

PRETEXT 3-4 tumors get biopsy plus neoadjuvant chemo, not upfront resection — this shift drove survival from <30% to 80-90%
Right hepatic vein separates anterior (5,8) from posterior (6,7) sections; right portal vein separates superior from inferior
PRETEXT stage = 4 minus number of tumor-free contiguous sections; stages 3-4 require early transplant center consultation
Complete resection is the most important survival intervention; options include trisectionectomy, mesohepatectomy, or transplant
Hemangioma is the most common pediatric liver lesion; hepatoblastoma accounts for only ~250 cases/year in the US

Neuroblastoma vs Wilms: Which Is the Most Common Abdominal Malignancy in Children?

The points where the speakers disagreed, with each position presented side by side. Written by Kai from the episode transcript and reviewed before publishing.

For specialists · Points of disagreement · AI-written, human-reviewed

The Question

When a child presents with an abdominal mass, clinicians must maintain a broad differential [c4, c5]. Among malignancies, which tumor holds the distinction of being most common in the abdomen remains a point of genuine disagreement among pediatric surgeons [c4, c5].

The Case for Neuroblastoma

One discussant holds that neuroblastoma is commonly considered the most common abdominal malignancy in children, though acknowledging this is "somewhat controversial" 0:51. The reasoning rests on neuroblastoma's status as the most common solid malignancy in the pediatric population overall 1:13. This position treats abdominal neuroblastoma as the local manifestation of the most prevalent solid tumor system in children 1:13.

The Case for Wilms Tumor

The counterargument challenges the framing itself 1:13. While neuroblastoma is indeed the most common solid malignancy in children, "that's because there are tumors everywhere in the body" 1:13. By this logic, counting all neuroblastomas — thoracic, abdominal, pelvic, and elsewhere — inflates its apparent dominance in any single anatomic region 1:13. The second discussant argues that Wilms could be considered the most common abdominal malignancy precisely because neuroblastoma's total case count includes tumors arising outside the abdomen 1:13. If the question is specifically about abdominal primaries, Wilms may claim the higher frequency 1:13.

Where They Agree

Both discussants acknowledge the question is unsettled — one calls it "somewhat controversial," the other frames it as "a toss up between neuroblastoma and Wilms, depending on who you talk to" [c4, c5]. Neither disputes that both tumors are common, that both must remain high on the differential for an abdominal mass, or that the distinction matters less to initial workup than recognizing either possibility [c4, c5]. The disagreement is about how to count, not about clinical management at presentation 1:13.

They also agree implicitly that hepatoblastoma, despite being the most common malignant liver tumor in children, is nowhere near the most common abdominal malignancy overall, with only around 250 new cases per year [c1, c2]. The neuroblastoma-versus-Wilms debate operates in a different frequency range entirely [c1, c2, c5].

What Would Resolve It

The discussants do not propose a resolution, and the transcript offers no suggestion of what evidence would settle the question [c4, c5]. The disagreement appears to hinge on whether the most common abdominal malignancy should be defined by site of origin (favouring Wilms) or by total case burden in patients who present with abdominal disease (favouring neuroblastoma) 1:13. Resolving it would require agreement on the definition, then registry data stratified accordingly — a question of taxonomy as much as epidemiology 1:13. Until then, it remains what one discussant called it: a toss up, depending on who you ask 1:13.

Takeaways from this story

Neuroblastoma vs Wilms as most common abdominal malignancy remains unsettled, hinging on whether to count by site of origin or total abdominal burden.
Neuroblastoma is the most common solid malignancy overall in children, but tumors occur throughout the body, not just abdomen.
Hepatoblastoma, though the most common malignant liver tumor in children, represents only ~250 cases/year — far less common than either neuroblastoma or Wilms.

Topic overview

This discussion covers the diagnosis and management of hepatoblastoma, the most common malignant liver tumor in children with approximately 250 new cases per year in the United States. The speakers review the diagnostic workup including imaging with MRI using EOVIST contrast, the critical role of alpha-fetoprotein (AFP) in diagnosis and treatment monitoring, and liver anatomy segmentation essential for surgical planning. Treatment has evolved dramatically over the past 20-25 years, with survival rates improving from less than 30% in the 1970s-80s to 80-90% today, primarily through the adoption of neoadjuvant chemotherapy for advanced tumors and earlier referral to transplant centers. The PRETEXT staging system (based on number of contiguous liver sections free of disease) guides treatment algorithms, with PRETEXT 1-2 tumors often resectable at diagnosis while PRETEXT 3-4 tumors typically require neoadjuvant chemotherapy and may need liver transplantation.

Key takeaways

MRI with EOVIST contrast provides optimal liver imaging by hepatocyte uptake and excretion for surgical planning. (2:39)
PRETEXT 1-2 tumors with >1cm margin from middle hepatic vein/portal bifurcation should be resected at diagnosis. (6:34)
Neoadjuvant chemotherapy for PRETEXT 3-4 tumors improved survival from <30% (1970s-80s) to 80-90% today. (7:15)
Early transplant center consultation is critical for PRETEXT 3-4 disease to optimize resection vs transplant decisions. (7:31)
Complete resection remains the most important intervention for hepatoblastoma survival. (3:17)

Keywords

hepatoblastoma neuroblastoma Wilms tumor hemangioma hematoma focal nodular hyperplasia hepatocellular carcinoma precocious puberty liver biopsy MRI trisectionectomy mesohepatectomy liver transplantation hepatic resection EOVIST

Hashtags

Hashtags will be added soon through AI processing

Transcript

Click "Show Transcript" to view the full text (10105 characters)

Hepatoblastoma is the most common malignant liver tumor in the pediatric population. But treatment strategies have changed dramatically over the past 25 years. That's why today we're going to talk about the basics with an expert. So, Hepatoblastoma, there's around 250 new cases a year. Huge changes in terms of the treatment algorithm over the last 20 years. That's Dr. Greg Tiao. He is a pediatric transplant surgeon at Cincinnati Children's Hospital. He's going to walk us through some of the basics. So stick around. This is the Stay Current in Pediatric Surgery podcast. Okay, so I'll start by setting the scene. A child comes into the hospital with an abdominal mass. We're talking specifically about Hepatoblastoma today, but we should still have a very wide differential diagnosis. That's right. Hepatoblastoma is the most common malignant liver tumor in children, but it's nowhere near the most common liver tumor or the most common abdominal tumor. When I'm recalling the most common abdominal wall malignancy in children, I recall this being somewhat controversial, but most would consider it to be neuroblastoma. It's a toss up between neuroblastoma and Wilms, depending on who you talk to. Now neuroblastoma is the most common solid malignancy in the pediatric population, but that's because there are tumors everywhere in the body. So you could make an argument that Wilms is the most common. So we get our imaging and we figure out that the tumor is coming from the liver. So on our differential diagnosis, we should have hepatoblastoma, hemangioma, hematomas, focal nodular hyperplasia, and hepatocelular carcinoma. Common things being common, hemangioma should be pretty high on the list. Unfortunately, I'm not sure if Rajni jumped on or not, but she'll see many kids with liver lesions and their hemangiomas. The most common lesion is hemangioma. Even though hepatoblastoma is the most common malignant liver tumor in children, it's still pretty rare with about 250 cases per year. So you got to be pretty in tune with the wide range of presentations and have a high index of suspicion. Like Rod said, neuroblastoma has a wide spectrum of presentations. It can present as an asymptomatic abdominal mass, but on the other end of the spectrum, Dr. Tiao has seen it present as a tumor rupture or as a patient in respiratory distress due to the tumor size. It can also present as a perineoplastic syndrome like precocious puberty. But keep in mind that in any situation, an elevated alpha-phetoprotein, or AFP, is a key component in the workup. AFP is critical for the diagnostic algorithm, and it's a guide for treatment response. Okay, so to summarize, I see a kid and I'm suspicious because he has a large abdominal mass and he has an AFP in the 10,000s. Next we need to get axial imaging. Most experts are relying on MRI to delineate the anatomy and to evaluate the extent of liver involvement. MRI with EOVIST that we got today. What was that? What's EOVIST? EOVIST is an MRI contrast agent that is taken up by the hepatocytes and then excreted. It can provide the best definition when looking at the liver on imaging. If you're listening in the Stay Current app, scroll down under the media player. We're going to give you some images of EOVIST so you can take a look. I mean, it really does distinguish biliary anatomy. So to establish a diagnosis of hepatoblastoma, we need four things. We need to start with the history. Then we need to get our abdominal imaging. Then we need to check an AFP. And finally, we need to get a liver biopsy. The most important intervention for survival is to achieve complete resection. The way you get there can be varied. Primary goal is to achieve complete tumor removal. There's conventional resection and then there's more aggressive resections. Aggressive resections are when you're starting to think about a trisectionectomy, a mesohepatectomy, a resection with an additional procedure in the remnant liver, and of course, liver transplantation. As you're probably starting to figure out, a lot of the resection algorithms are based on liver anatomy and the pretext system. But before we get to that, Dr. Tiao, can you walk us through how to find all eight liver segments on axial imaging? That was correct. One is Caudate. Two and three are left lateral segments, superior and inferior. 4A, 4B is left medial segment. 5, 6, 7, 8 are the right side of the liver. Do you guys know how Cunode labeled them in this clockwise circle? He injected them into portal vessels. And so that's really how these are labeled. But he labeled them in this counterclockwise fashion after, I can never pronounce this, but the districts of Paris are done in the same fashion. Hmm. That actually makes sense in a strange way. When we look at the right side of the liver here, you guys see this here is the vena cava right here. So Al, how do we differentiate 5 and 8 versus 6 and 7? What's the anatomic marker that allows us to differentiate between the anterior and posterior sections of the liver, of the right liver? That looks like the right hepatic vein there. You see this right hepatic vein coming out here? And so what we're actually seeing that track out. And then how do we separate between superior and inferior? That looks like the right portal vein coming in there. So right anterior is going to be segment 8 and that is going to be anterior to the right hepatic vein and superior to the right portal vein. 5 is right inferior and that's based off the right portal vein inferior and anterior to the right hepatic vein. 6 and 7 in that same fashion, 7 superior and 6 inferior. Okay, now would be a really good time for a diagram of the anatomy. Conveniently, we've put one in the media player for you. So scroll all the way down in the app and you'll find it. And the reason that all matters is because there's something called the pretext staging system. We need to classify our tumors in a more anatomically understandable fashion. And so the sections of the liver, the right posterior section is 6 and 7 and the right anterior is 5 and 8 is considered the right sections of the liver. And segment 4 is considered the left medial segment. A section in the segment 2 and 3 is the left lateral. And depending on if you had tumor in those stages, in those sections, the number of free sections without tumor is a minus 4 is your pretext stage. We've also included a table of the pretext system to review. So pretext 1 has 3 contiguous sections free of disease. Pretext 2 has 2 contiguous sections free of disease. Pretext 3 has 1 free section and pretext 4 has no free sections or diffused tumor burden in all sections of the liver. Additionally, this staging system is the framework for the treatment algorithm. Pretext 1 and 2 tumor, if there was greater than a centimeter margin from the middle hepatic vein and the portal bifurcation, you could offer, you should be considered for resection and diagnosis. Patients with bigger tumors that did not get resected would then be risk stratified to intermediate, low risk or intermediate risk. And then depending on annotation factors, if they had a positive, they could be in high risk. Pretext 3 and 4 is the big game changer. This change in practice is what improves survival rates for patients with hepatoblastoma from less than 30% in the 70s and 80s to between 80 and 90% today. And we had surgical guidelines for pretext 3 tumors and teach these patients to generally be biopsied in diagnosis and then started on neoadjuvant chemotherapy. And then depending on how they responded, be ready to send them to a transplant center or a center that has expertise to do more advanced liver resections. And then pretext 4 patients had a much more complicated schema. And the reason we had to do that was some of these patients needed to be transplanted. So if you have pretext 3 or 4 liver disease, there are specific indications to transplant, mainly if it's unresectable disease, whether it's unsafe to resect, or a resection would leave the patient with an inadequate liver remnant. But the main thing to get out of this is it's important to consult a transplant center. And the earlier the better. You refer these patients to liver transplant programs much earlier. And this is why we see so many more patients nowadays than perhaps when Fred and Maria were running the program 15 years ago. Because teams are trained to recognize tumors and send them to a center that offers transplant or can do aggressive resection. And if you'd like more information on the survival benefits of liver transplantation, you guessed it, it's in the link below. After clarifying the pretext stages you're not quite done, there's an ongoing trial to better delineate the treatment algorithms for each of the stages of hepatoblastoma. Sheik is responsible for an ongoing multinational trial called FIT, or the Pediatric Hepatic International Tumor Trial. The aim is to identify high and low risk features for each of the pretext stages. The FIT study has been going on now for three years. We've had the privilege of contributing to it in terms of its development. That's why we see a lot of tumors here. The treatment for hepatoblastoma has really evolved significantly. This is the schema for the study. This is the schema for hepatoblastoma and we'll break down this down a little bit more in just a second. No worries. Details for this study and others can be found in the links below. Management of these malignant liver tumors continues to improve through improved treatment, multidisciplinary teams, international collaborative efforts, and research. Thank you for joining us for this update on pediatric hepatoblastoma. And remember to check out the link below for the full lecture. Follow us on social media. Subscribe to our YouTube page. Download the Stay Current Pediatric Surgery app. It's in the Apple App Store. It's in the Google Play Store. Or if you're listening to us on an audio podcast, leave us a comment, a suggestion, a rating. It helps with the algorithm. And remember, knowledge should be free.

Comments

Loading comments...