Cancer precision medicine includes personalized treatment, prognosis prediction and cancer prevention for both affected and unaffected individuals. Personalized treatment has been improved after comprehensive genome profile (CGP) has been covered by national health insurance in June 2019. On the other hand, the concept of cancer precision medicine includes cancer prevention for unaffected people. Reliable reduction of cancer death can be succeeded by intervening in people who have not developed cancer. Gynecological oncologists can contribute to the reduction of cancer deaths among the people using individual genomic information for both unaffected and affcted individuals.

Therapy-related myeloid neoplasms (t-MN) following exposure to poly (ADP-ribose) polymerase inhibitors (PARPi) are relatively rare complications associated with poor prognosis. Here we report a case of therapy-related acute myeloid leukemia (t-AML) presenting prolonged bicytopenia without blasts or dysplasia in peripheral blood smear during PARPi maintenance therapy for ovarian cancer. A 61-year-old woman underwent interval cytoreductive surgery after 3 cycles of chemotherapy (carboplatin plus paclitaxel). Complete response was achieved following additional 6 cycles of adjuvant chemotherapy. At 3 years after surgery, relapse occurred in the liver and subcutaneous lower abdominal wall. After 4 cycles of chemotherapy (carboplatin plus paclitaxel), complete resection of subcutaneous lesion was achieved. She received 3 cycles of adjuvant chemotherapy followed by olaparib maintenance therapy. From the 4th month of maintenance therapy, prolonged anemia and thrombocytopenia were observed and she received transfusion several times. Although no blast or dysplastic cell was observed in the peripheral blood smear, the diagnosis of t-AML was confirmed by bone marrow examination. Since cytopenia during PARPi maintenance therapy is common, it is challenging to suspect t-MN. Our experience suggests prolonged cytopenia during PARPi therapy should prompt further investigations including bone marrow examination.

Atypical placental site nodule (APSN) develops from the trophoblast, and is considered as a precursor to epithelioid trophoblastic tumor (ETT). We report a case of accidental coexisting APSN and ovarian cancer. A tumor was discovered in the pelvis of a woman who complained of lower abdominal pain. On the basis of imaging and cytology findings, an ovarian tumor was suspected. However, an endometrial biopsy revealed other atypical cells that had multiple distinct nuclei with eosinophilic or clear cytoplasm and proliferated in an alveolar or fascicular pattern.

Low-grade endometrial stromal sarcoma (LGESS) is a rare disease that accounts for 0.2%of all malignant tumors of the uterine corpus. Cytotoxic anticancer drugs have little effect on advanced LGESS, and hormone therapy, such as aromatase inhibitors, is recommended.

A 45-year-old woman (2 gravida, 2 para) visited a local gynecologist because of left lower abdominal pain and a mass in the pouch of Douglas was found. Exploratory laparoscopy revealed disseminated lesions in the pouch of Douglas and the abdominal cavity. The pathological diagnosis of the lesions was LGESS and she was referred to our hospital. Lower gastrointestinal endoscopy revealed rectal mucosal invasion and she was diagnosed with LGESS, stage IVB. As complete resection of the disseminated lesions was not possible, we performed tumor reduction surgery. Total abdominal hysterectomy, bilateral salpingo-oophorectomy, ileal resection, and Hartmann' s surgery were performed, and the pathological diagnosis was LGESS (pT4NXM1). Aromatase inhibitors were administered postoperatively for the residual lesion, and no progression or recurrence was observed 1 year and 2 months after the operation. Aromatase inhibitors for LGESS are not covered by insurance in Japan but should be considered as one of the treatment options.

There are few reports of uterine cervical neuroendocrine carcinoma (NEC) during pregnancy, and there are no definite treatment guidelines. We experienced a case of NEC diagnosed at 21 weeks' gestation. The patient was a 29-year-old female who had one child. A 20 mm polypoid mass was found in her cervix at 21 weeks' gestation. Histopathology confirmed NEC, and the tumor was 15 mm in diameter and diagnosed as cervical cancer stage IB1. Since the tumor diameter was less than 20 mm and no lymph node metastasis was observed, we decided to wait until 26 weeks' gestation. However, on the second day of the 24th week of gestation, the tumor rapidly grew, and an emergency cesarean section and radical hysterectomy were performed. The baby weighed 577 g and was growing well. Pathological examination revealed small-cell NEC with closed lymph node metastasis (pT1b2N1M0). Four cycles of postoperative PE therapy were administered, but pelvic recurrence and liver metastasis occurred within five months, and the patient died 10 months after surgery. Since uterine cervical NEC generally progress rapidly, when diagnosed during pregnancy, careful consideration of the gestation period and impact on the fetus is necessary for decision-making.