Primary retroperitoneal mucinous cystadenocarcinoma (PRMC) is a rare disease and mostly occurs in females, and there are only three male cases described in the literatures without long-term follow-up.
A 59-year-old male presented with a left retroperitoneal cystic mass (7.5 ´ 7 ´ 3 cm) that upwardly displaced the left kidney and caused abdominal discomfort. The tumor was totally excised by the hand-assisted laparoscopic method without complications or recurrence in a follow-up period of 79 months. The etiology from coelomic metaplasia of peritoneal epithelium was proved by a spectrum of diverse cells (benign, borderline malignant, and malignant cells) during pathological examination.
This is the fourth male case of PRMC in the world with a favorable outcome after hand-assisted laparoscopic excision, and this is also distinct by the longest follow-up period in this disease entity.
Because of its low-malignant potential and recurrence rate, surgical excision is still the best choice of treatment, but the least invasion method should be adopted in front.