Mullerianosis is a rare choristoma of Mullerian-derived tissues. It differs from endometriosis in that at least two types of Mullerian-derived tissue is present.

The pathogenesis of Mullerianosis is not completely understood, but the majority of cases occur in the bladder wall. The biopsy-proven Mullarianosis in the case above would be slightly atypical to most recorded cases since it is centered in the abdominal wall and since the patient has had pelvic surgery (hysterectomy).

Mullerianosis has been described in the literature as multiloculated and cystic, but imaging features are nonspecific and the diagnosis is made on histology.

In this case, the diagnosis was made after biopsy.