Pre-operatively misdiagnosed undifferentiated embryonal sarcoma of the liver: analysis of 16 cases.

BACKGROUND: To investigate the clinical features of undifferentiated embryonal sarcoma of the liver (UESL) to improve its preoperative diagnostic accuracy.

METHODS: The clinical, imaging, and histopathologic findings of 16 UESL patients whose disease was pathologically confirmed but preoperatively misdiagnosed were retrospectively analyzed.

RESULTS: Among these 16 patients, 9 were clinically misdiagnosed as primary liver cancer, 3 as hepatoblastoma, and 4 as malignant hepatic mass. In 12 patients who were presented due to abdominal discomfort, ultrasound showed that predominantly solid lesions, whereas computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated predominantly cystic masses within irregular soft tissue. Contrast-enhanced imaging showed enhancement intralesional foci, multiple internal septations, and edges. The postoperative pathology showed the cutting surface of tumors was variegated, with solid and cystic gelatinous areas, hemorrhage, and necrosis. Intracytoplasmic hyaline globules were commonly present among cancer cells.

CONCLUSIONS: UESL is a rare clinical condition without specific clinical manifestations. The inconsistencies between ultrasound and CT/MRI findings may be helpful to improve the preoperative diagnosis accuracy.