Mullerian cyst of the upper abdomen

Mullerian cysts are rare retroperitoneal lesions, the majority of which occur in women.

Most develop in the pelvis but a few involve the upper abdomen, manifesting as a mass at the tail of the pancreas.

The cysts are large and often displace adjacent organs. Precise preoperative diagnosis is seldom possible.

Surgical excision is curative, but many cysts are multilocular and may recur if removal is incomplete.

Histologically the lining is epithelium, ordinarily ciliated but occasionally mucinous. The cyst wall usually includes some smooth muscle.

In women, mullerian cysts may occur within the pelvis (where they clinically mimic ovarian lesions) or in the upper abdomen. They also occur in the pelvis in men.