S6049 An Uncommon Culprit: Small Bowel Metastasis From Serous Ovarian Carcinoma Presenting With Iron Deficiency Anemia

Introduction: Primary malignancies of the small bowel are rare, accounting for approximately 1% to 5% of all gastrointestinal cancers. Secondary metastatic lesions to the small bowel from distant primary tumors are even less common, with incidences ranging from 0.2% to 0.7%. Ovarian carcinoma, a malignancy associated with poor prognosis, predominantly manifests from epithelial tissue. These include mucinous, endometrioid, clear cell, and serous histological subtypes. Common metastatic sites of ovarian carcinoma include the uterus, fallopian tubes, peritoneum, chest, and liver. In contrast, gastrointestinal metastasis from ovarian cancer is rarer, accounting for only 0.013% to 1.6% of all gastric metastatic tumors. Case Description/Methods: A 62-year-old woman with a medical history significant for hypertension, hyperlipidemia, iron deficiency anemia, and stage IVa serous ovarian cancer on chemotherapy presented with epigastric pain and melena. Patient reported persistent postprandial abdominal pain and emesis for the past 6 months. An esophagogastroduodenoscopy (EGD) performed 2 months prior demonstrated gastritis and esophagitis, with an otherwise normal duodenum. On admission, notable laboratory results included hemoglobin 6.4 g/dL (baseline around 10 g/dL), iron saturation of 5%, and an elevated carcinoembryonic antigen-125 (CA-125) of 1,351 U/mL. A computed tomography angiogram (CTA) of the abdomen showed no evidence of active gastrointestinal bleeding, but did demonstrate findings consist with peritoneal carcinomatosis. Given the recent negative EGD and persistent symptoms, push enteroscopy was pursued for further evaluation. Enteroscopy noted a normal esophagus, stomach, and duodenum, but identified a mass in the mid-jejunum. Biopsies were obtained, and immunohistochemical staining was positive for CK7, PAX-8, and WT-1 tumor markers. These findings were consistent with metastatic serous carcinoma of Muellerian origin. Discussion: Ovarian cancer represents a significant cause of mortality in women, with serous ovarian cancer often demonstrating a highly aggressive clinical course. While small bowel malignancies are rare, metastatic involvement of the gastrointestinal tract from ovarian cancer is even more uncommon. Therapeutic options for metastatic ovarian carcinoma are limited. Despite its low rate of occurrence, it is imperative to consider gastric metastasis in the differential diagnosis for patients presenting with iron deficiency anemia, melena, and prior history of ovarian malignancy.