An unusual presentation of ovarian carcinoma with supraclavicular lymph node and colorectal metastases leading to spontaneous rectovaginal fistula

INTRODUCTION AND IMPORTANCE: Secondary metastases to the rectum from primary ovarian cancer are a rare entity and their diagnosis and management are challenging. In this report, we discuss the findings of the case of metastatic ovarian cancer to supraclavicular lymph nodes and the rectum complicated with rectovaginal fistula. CASE PRESENTATION: A 68-year-old woman was admitted for abdominal pain with rectal bleeding. Pelvic examination revealed a left latero-uterine mass. Abdominal-pelvic CT scan showed a tumor mass on the left ovary. A cytoreductive surgery and resection of a non-imaged rectal nodule identified during surgery were performed. The tumor specimens including the rectal metastasis were immunohistochemically confirming a metastatic ovarian cancer using CK7, WT1 and CK20. The patient received chemotherapy and had complete remission. However, she had a recto-vaginal fistula confirmed by imaging and had developed right supraclavicular lymphadenopathy from ovarian cancer later. CLINICAL DISCUSSION: The dissemination of ovarian cancer in the digestive tract can be frequently, through direct invasion, abdominal implantation and lymphatic system. Unusually, ovarian cancer cells may spread to supra-clavicular nodes, because of the connection of the two diaphragmatic stages allowing the lymph flows through the lymphatic vessels. Moreover, rectovaginal fistula is an uncommon complication which can be seen spontaneously or due to certain patient's features. CONCLUSION: In advanced ovarian carcinoma, it is required to properly assess the digestive tract during surgery because imaging can miss metastatic lesions such as our case. The use of immunohistochemistry is recommended to differentiate between primary ovarian carcinoma and secondary metastasis.