Abstract
A 59-year-old woman presented with an abdominal mass. Contrast-enhanced computed tomography (CT) revealed a solid mass encompassing the left kidney, consisting mainly of a low-density area suggestive of fat, and containing some heterogeneous high-density areas. Based on imaging findings, we diagnosed retroperitoneal dedifferentiated liposarcoma. During surgery, we suspected the tumor was directly invading into the pancreas and transverse colon. We therefore performed left nephrectomy, combined distal pancreatectomy and splenectomy, and partial transverse colectomy. The excised specimen weighed 3,500 g and was pathologically diagnosed as dedifferentiated liposarcoma. Although the aortic separated surface was tumor cell-positive, we judged that the tumor had been macroscopically resected and discharged the patient for follow-up. Contrast-enhanced CT taken 1 postoperatively revealed a nodular shadow in the right lung field, suggestive of metastasis. The patient then underwent right upper lobe segmentectomy. Postoperative pathological examination gave a diagnosis of lung metastasis of dedifferentiated liposarcoma. No recurrence, distant metastasis, or new lesion has since been detected. We report here this rare case of dedifferentiated liposarcoma that remained recurrence-free after resection of the primary tumor and metachronous lung metastasis, and review some of the literature.
