Hepatoblastoma: Update Course 2014

PRETEXT staging stands for pretreatment extent of disease and is based on segmental liver anatomy prior to chemotherapy

PRETEXT staging has a tendency to overstage because it is based purely on imaging and bulky tumors make it hard to assess true vascular invasion versus mass effect

POSTTEXT refers to extensive disease after neoadjuvant chemotherapy has been given

Key staging annotations include involvement of the retrohepatic cava or hepatic veins and the portal vein bifurcation

COG recommendations state that PRETEXT stage 2 tumors with no vascular involvement and achievable 1 cm margin can be resected upfront without neoadjuvant chemotherapy

COG feels that PRETEXT stage 1 and 2 tumors do not necessarily need referral to centers with liver resection expertise if the local surgeon feels competent

Most tumor shrinkage from chemotherapy occurs within the first two cycles

Current recommendations are that after two cycles of chemotherapy, if the tumor has not shrunk to a resectable point, the patient should be evaluated for transplant

As hepatoblastoma tumors shrink with chemotherapy, they do not shrink away from the vascular supply, so chemotherapy does not improve vascular margins

The goal surgical margin for hepatoblastoma resection is 1 cm

Survival in patients undergoing extended or heroic resections (tumor liver explants with back table resection and reimplant, portal vein reconstructions, hepatic vein reconstructions) is not as good as transplant survival

There has been a move away from heroic resections for hepatoblastoma

Patients who undergo failed resection followed by rescue transplant have worse survival than patients who undergo planned transplant upfront

Patients should be referred to a transplant center early even if they may not ultimately need transplant, to have pre-transplant evaluation completed and be plugged into the system

Primary transplant patients with hepatoblastoma do surprisingly well despite immunosuppression against rejection in the setting of cancer

For non-transplant center surgeons, criteria for proceeding with resection include feeling 95% confident of success and ability to perform an anatomic resection with good margin

Disease close to hepatic veins, disease extending across the liver, or involvement of the portal vein should prompt referral to a transplant center

The truth about resectability is determined at the time of operation despite all available imaging

In Europe, all liver tumors receive chemotherapy upfront before surgery because it results in smaller, easier-to-resect tumors

Core needle biopsy for hepatoblastoma typically requires about 10 passes through an area that includes normal parenchyma and tumor

There are two camps regarding pulmonary metastasis treatment: one advocates resecting metastases upfront before hepatectomy, the other suggests waiting until after hepatectomy because liver regeneration growth factors may stimulate previously unrecognized lung sites

There is no good data on either side of the pulmonary metastasis timing debate, with both approaches limited to a handful of patients

Papers on stage IV hepatoblastoma with lung metastases are limited to cohorts of less than 20 patients, making it hard to draw good conclusions

There may be reporting bias in transplant outcomes because successes are reported but not all failures