Leiomyosarcoma arising from the ovarian vein has rarely been reported. Herein, we report two cases from a single institute. Given their direct connections to ovarian vessels, both leiomyosarcomas were initially suspected to be gynecological malignancies. In one case, leiomyosarcoma was discovered incidentally without any clinical symptoms; it had a close connection with the ovarian vein, was removed surgically, and the patient has survived for over 12 years. In another case, bowel obstruction caused by the tumor helped to identify metastatic leiomyosarcoma. Blood flow was supplied by the ovarian artery and grew into the lumen of the ovarian vein without invading adjacent organs. After surgical resection, the patient underwent 18 months of chemotherapy prior to palliative care. We propose that leiomyosarcoma arising from the ovarian vein should be treated as a gynecologic malignancy, especially if it develops in the lower abdomen.

Advanced carcinoma of the lower female reproductive tract is rare during pregnancy and the postpartum period. We here present a case of a 32-year-old Japanese woman, whose entire lower reproductive tract had been invaded by carcinomas as of 2 months after childbirth. She had been infertile, and pregnancy had been established by repeated embryo transfer. The gynecological cancer screening, which included Pap smear tests, was negative during the periods she underwent infertility treatment or during the first trimester. At 26 gestational weeks, the patient noticed uterine contractions concomitant with genital bleeding. Labor progressed slowly and steadily; thus, the pregnancy was ended by cesarean section at 29 weeks. At 2 months after childbirth, the patient experienced increased left abdominal pain and underwent a pelvic examination, revealing multiple pelvic masses and diffuse vaginal tumors causing stenosis. Vaginal tumors were biopsied, and histochemical analysis showed undifferentiated carcinoma with possible adenocarcinoma. Imaging modalities including CT, MRI, and PET-CT suggest that the carcinoma had invaded the entire reproductive tract, especially the uterine body, metastasized into the lungs and the ischial bones, and disseminated onto the peritoneum. She received multiple rounds of chemotherapy but died 6 months after childbirth. Taking into consideration the clinical feature and immunohistochemical profiles of the cancer cells, the endometrium is the most likely origin.