Pitfalls in the Surgical Management of Undifferentiated Sarcoma of the Liver and Benefits of Preoperative Chemotherapy

AimUndifferentiated sarcoma of the liver (USL) is the third commonest malignant liver tumor in children. The aim of our study is to evaluate the outcome of this rare entity according to the quality of the surgical resection and the compliance to the European pediatric soft tissue sarcoma group guidelines. Patients and MethodsWe conducted a monocentric review of patients referred to our department with a definitive pathologic diagnosis of USL between 1997 and 2013. We looked at the diagnosis and management pitfalls, surgical technique, and outcomes. Results are expressed as median (range). ResultsThere were 13 patients (M/F=7:6=1.1). Age at presentation was 8 years (range, 11 months-16 years). Of the 13 patients, 10 patients (69%) presented with abdominal pain, 5 (38%) with tumoral bleeding, and 2 (15%) with peritoneal rupture. All lesions were unique, nonmetastatic, and heterogeneous with cystic components measuring 14 (6-19) cm. Six (46%) patients had an upfront surgery: five because of wrong clinical diagnosis (three query mesenchymal hamartoma, one spontaneous peritoneal bleeding, and one cystic lymphangioma), and one because of rapid enlargement of the mass. Seven (54%) patients (including one with tumoral bleeding) received neoadjuvant chemotherapy, and had their tumor diameter decreasing by 40% (range, 0-60%). Final surgery consisted of seven right hepatectomies; one right extended hepatectomy; three mesohepatectomies; two left hepatectomies. There were three incomplete resection in the upfront surgery group versus none in the neoadjuvant chemotherapy group. The degree of tumor necrosis after chemotherapy ranged from 95 to 100%. Surgical complications included the following: liver transplantation (LT) following a Budd-Chiari syndrome after a mesohepatectomy, one biliary ducts injury treated by Roux-en-Y loop. All patients received the postoperative chemotherapy according to the European protocol. One of seven patients (14%) with neoadjuvant chemotherapy underwent radiotherapy for rupture at diagnosis versus three of six patients (50%) with upfront surgery: one for rupture at diagnosis and two for rupture during upfront surgery. One patient (17%) with upfront surgery had local recurrence at 2 years after initial surgery, and is in second complete remission 1year after a redo surgery. All patients are alive at a median 34 months (range, 5-134) follow-up. ConclusionUSL presents with painful mixed cystic and solid liver mass. If misdiagnosed and mistreated (enucleation or unroofing), the usual good outcome of this malignancy could be impaired. Preoperative chemotherapy is recommended.