Imaging Results of Retroperitoneal Malignant Mesenchymoma: A Case Report

Retroperitoneal malignant mesenchymoma is a rare retroperitoneal neoplasm with poor prognosis. Here we present a patient with retroperitoneal malignant mesenchymoma. A 32year-old man presented with progressive painful swelling on his left lower leg, abdominal fullness and a palpable left abdominal mass. Imaging studies of abdomen included sonography, contrastenhanced computed tomography (CECT) and magnetic resonance imaging (MRI). CECT showed a huge, heterogeneously enhanced tumor with multifocal intratumorous calcifications in the left retroperitoneum. On MRI, the neoplasm was predominantly hyperintense on T1-weighted MR images and predominantly hyperintense , mixed with central isointense areas on T2-weighted images. Surgical resection of this retroperitoneal neoplasm was performed, and two courses of postoperative adjuvant chemotherapy were then administered. Unfortunately, a follow-up CT study obtained 1.5 months and 11 months after the operation showed local tumor recurrence. The patient died 17 months after the initial operation.