Surgical resection is generally not recommended for patients with distant metastasis of breast cancer. However, we report a case in which bilateral salpingo-oophorectomy for a unilateral ovarian tumor with no preoperative suspicion of malignancy was helpful in the treatment of recurrent breast cancer. The patient was a 49-year-old woman who underwent surgery for invasive ductal carcinoma of left breast at the age of 41 years. Because the tumor was hormone sensitive, the patient was treated with radiotherapy, luteinizing hormone-releasing hormone (LHRH) agonists, and tamoxifen for 5 years after surgery. Approximately 7 years after surgery, she was found to have multiple bone metastases. Therefore, radiation, LHRH agonist, and aromatase inhibitor therapies were initiated. After the initiation of LHRH agonist therapy, a 4-cm right ovarian cyst appeared, which slowly increased in size to 6 cm over 1 year. She visited our department, and magnetic resonance imaging revealed a unilateral polycystic ovarian tumor with some solid components but with no apparent evidence of malignancy. Laparoscopic bilateral salpingo-oophorectomy was performed. The postoperative pathological diagnosis was breast cancer metastasis with estrogen receptor positivity. This surgical intervention not only enabled pathological search and resulted in surgical menopause but also identified biomarkers in the tissue of the removed tumor, which was useful in planning the treatment strategy for recurrent breast cancer.

There are several reports of postoperative chylothorax from thoracic surgery field, but none from gynecologists. We report two cases of chylothorax after paraaortic lymphadenectomy of ovarian cancer.

Case 1: A 45-year-old woman underwent primary debulking surgery, including paraaortic lymphadenectomy for ovarian cancer. In the subsequent 6 days, she developed right pleural effusion and was diagnosed as chylothorax. The pleural effusion resolved with drainage and a low-fat diet within a month.

Case 2: A 44-year-old woman underwent primary debulking surgery, same as case 1. After 6 days of surgery, she developed right pleural effusion and was diagnosed chylothorax. There was no evidence of ascites. The patient was treated conservatively; drainage and fat-free intravenous nutrition. A month passed then, but the effusion did not decrease. In this case, lymphangiography was not effective to detect the leakage. With the chest tube inserted, she received adjuvant chemotherapy. Overall, it took half a year for the effusion to resolve. Postoperative chylothorax may take months to settle with conservative treatment alone.

Small-cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare tumor that occurs mainly in young women and has a very poor prognosis. We report a case of SCCOHT that developed in the contralateral ovary 16 years after initial treatment during childhood; therefore, it was considered metachronous. When the patient was 14 years old, she underwent left adnexectomy and adjuvant chemotherapy (vincristine + cyclophosphamide + etoposide + cisplatin) for ovarian primitive neuroectodermal tumor (PNET). She had been without recurrence until the age of 30, when she presented with abdominal pain and constipation. An 11-cm right ovarian tumor was found, suggesting the recurrence of PNET. Debulking surgery was performed, but less than 1 cm of dissemination still remained in the abdominal cavity. The pathological diagnosis was SCCOHT, elucidated by the SMARCA4/BRG1 immunostaining. The histopathological findings were similar to those from her childhood, suggesting multiple metachronous tumors. Although two courses of adjuvant chemotherapy with cisplatin and etoposide were administered, the tumor progressed, and the patient died 3.5 months after surgery. This case suggests that SCCOHT should be included in the differential diagnosis of childhood-onset malignant ovarian tumors that require long-term continuous observation due to the risk of metachronous recurrence.