A Case of Laparoscopically Removed Primary Retroperitoneal Mucinous Cystic Tumor with Borderline Malignancy

Abstract

A 22-year-old woman presented to our hospital with a chief complaint of right lower abdominal pain. Physical examination revealed an elastic fist-sized mass with poor mobility and mild tenderness on palpation of the right abdomen. Abdominal contrast-enhanced computed tomography (CT) scan showed a cystic mass, 86×70×54 mm in size, in the right paracolic gutter and the ascending colon compressed and displaced ventrally and medially. MRI performed 2 weeks later demonstrated similar findings except that the mass increased in size to 90×72×67 mm. Primary retroperitoneal cystic tumor was diagnosed, and a retroperitoneal tumor resection was performed laparoscopically. After carefully detaching the tumor from the surrounding tissues, to avoid damaging the tumor membrane, the tumor was placed in an endobag inside the abdominal cavity and removed through the umbilical port site by aspirating the tumor contents. Histopathological examination revealed primary retroperitoneal mucinous borderline malignant tumor with ovarian-like stroma in the cyst-like wall. Twenty-four months after surgery, there has been no recurrence. We report this case with a review of other cases in Japan.