Retroperitoneal Myoepithelial Carcinoma: A Case Report and Literature Review

Myoepithelial carcinoma is rare, and myoepithelial carcinoma occurring outside the head and neck is even rarer. We reported one case of retroperitoneal myoepithelial carcinoma.

A 63-year-old woman who underwent computed tomography (CT) for progressive abdominal distension revealed a left retroperitoneal mass and subsequently underwent surgical treatment where the mass was completely removed with a postoperative diagnosis of retroperitoneal myoepithelial carcinoma. A follow-up CT review 40 days after surgery revealed a recurrence of the mass. After 8 months of chemotherapy and targeted immunotherapy, a follow-up review of the CT images revealed a gradual reduction in the mass. Four months after the cessation of chemotherapy and targeted drug combined immunotherapy, a follow-up review via CT revealed another recurrence and enlargement of the mass.

CT of retroperitoneal myoepithelial carcinoma revealed a massive cystic solid mass in the abdominal cavity and retroperitoneum. The solid region of the mass was significantly enhanced and the cystic region was without enhancement on enhanced CT; the mass involved the adjacent duodenum, partial jejunum, and left renal vein. PET‒CT imaging revealed hypermetabolism in the solid region of the mass and no hypermetabolism in the cystic region.