Undifferentiated embryonal sarcoma of liver: a multi-institutional experience with 9 cases.

To summarize the clinicopathological features, therapeutic regimens and outcomes for the patients with undifferentiated embryonal sarcoma of the liver (UESL), 9 cases of UESL were retrospectively reviewed. Complete clinical history, lab studies, imaging examinations and pathological findings were collected for analysis. Overall survival and progression free survival were assessed by Kaplan-Meier Survival Analysis. The patients were 6 to 37 years old, and included 6 males and 3 females. The tumor size ranged from 5 to 26 cm. Pathologically, the tumors consisted of proliferations of medium sized spindle, oval or stellate shaped pleomorphic cells loosely or compactly arranged in an edematous or myxoid matrix, with scattered bizarre multinucleated giant cells. All of the 9 cases were treated with radical resections, 6 of 9 cases received chemothrepy for postoperative treatment. All follow-up data were available, 4 of 9 cases had recurrence, and 2 patients were died. Time to recurrence in these cases was 19, 4, 29, 14 months. The mean overall survival (OS) was 58.25 ± 9.1 months and the mean progression-free survival (PFS) was 39.55 ± 11.6 months. UESL is a potential treatable malignance when treated with combined multiagent chemotherapy after resection.