Dedifferentiated liposarcoma in the abdominal cavity: a case report.

Liposarcoma adherent to the mesentery is extremely rare and difficult to diagnose. A 70-year-old woman presented to the hospital with a right lower abdominal mass. After surgical resection, the patient was diagnosed with dedifferentiated liposarcoma of the transverse colon with a mesenteric origin, and chemotherapy was administered. Diagnosing dedifferentiated liposarcoma of the transverse mesocolon based on imaging findings alone is challenging. Surgical resection can aid diagnosis. Moreover, cancer-specific genetic testing was performed in this case because dedifferentiated liposarcoma is a disease for which novel therapeutic agents are expected to be developed.