2017 Volume 69 Issue 3 Pages 293-299
Malignant transformation of a mature cystic teratoma of the ovary is uncommon, and transformation to adenocarcinoma is especially rare. The current authors encountered a case of an ovarian mature cystic teratoma with spontaneous rupture, which was suspect of malignant transformation to adenocarcinoma. This case involved a 46-year-old woman, gravida 0, who was seen at a clinic for epigastric pain, a stomachache, a fever, and diarrhea. The woman was diagnosed with acute enterocolitis and she was given medication, but her condition failed to improve. Two days later, the woman was seen by internal medicine at a general hospital. Rupture of an ovarian tumor was suspected, and the women was referred to this department in the same day. A computed tomography (CT) scan revealed a multilocular cystic mass 8 cm in diameter with a solid component located in the lower abdomen and ascites around the liver. The patient was diagnosed with spontaneous rupture of an ovarian mature cystic teratoma, and she underwent laparoscopic right salpingo-oophorectomy. After surgery, histopathology indicated that the solid component was an admixture of endometrioid and clear cell adenocarcinoma, and the patient was diagnosed with suspicious of malignant transformation to adenocarcinoma of ovarian mature cystic teratoma. The patient underwent a staging laparotomy, and ovarian cancer was FIGO stage IC2 (pT1c, N0, M0). The patient underwent adjuvant chemotherapy with paclitaxel and carboplatin, and the cancer had not recurred two years postoperatively. [Adv Obstet Gynecol, 69 (3) : 293-299 , 2017 (H29.8)]
