Hyperreactio luteinalis. Benign disorder masquerading as an ovarian neoplasm.

Hyperreactio luteinalis (HL) refers to moderate to marked cystic enlargement of the ovaries due to multiple benign theca lutein cysts and is most often associated with hydatidiform mole or choriocarcinoma. The cause of this condition is unknown, but is believed to be related to elevated levels of, or abnormal ovarian response to, human chorionic and pituitary gonadotropins. Only 47 cases of HL unassociated with trophoblastic disease have been previously reported in the English-language literature, mostly before 1974, and almost exclusively in the gynecologic literature. We present two additional cases of HL unassociated with trophoblastic disease and review the literature. One of our case reports documents the unusual occurrence of unilateral HL. Of the 49 cases described, 11 occurred with fetal hydrops (8 immunologic; 3 non-immunologic), 8 with multiple pregnancies, and 30 in otherwise normal single pregnancies. Hyperreaction luteinalis is most often bilateral and found incidentally at the time of cesarean section. However, HL may present during any trimester as an abdominal mass or acute abdomen. The natural course is postpartum regression. Recognition of HL is important, since misinterpretation at laparotomy or erroneous histologic diagnoses have resulted in unnecessary surgery, often with sterilization in 16 of the cases. A conservative approach is indicated with wedge biopsy and frozen section diagnosis. Oophorectomy is necessary only to remove infarcted tissue or to control hemorrhage.