S1811 Cecal Ulceration as the Presenting Finding of Metastatic Breast Cancer: A Case Report and Review of Literature

Abstract

Introduction: Breast cancer is the second most common malignancy worldwide and the second leading cause of cancer mortality in women. Despite routine screening, early detection, and evolving treatment modalities, recurrence and metastatic disease often occur. While breast cancer metastases are traditionally identified in the lung, liver, and bone, metastases to the gastrointestinal tract are rare. Metastases to the stomach are more commonly identified than to the colon and rectum. Prior cases of metastatic breast cancer to the gastrointestinal tract are reported in individuals with an established diagnosis of breast cancer. We describe a case of an ulcerated lesion in the cecum as the initial presenting sign of metastatic primary breast cancer. Case Description/Methods: A 64-year-old-woman with hypertension and chronic constipation was referred to our institution for evaluation of seven weeks of fatigue, one week of urinary symptoms, and lower extremity edema. The patient had undergone ten years of unremarkable screening mammograms. On admission, laboratory workup was notable for markedly elevated liver enzymes. Computerized tomography scan indicated evidence of an ileocecal valve mass and extensive diffuse hepatic metastases. Endoscopic evaluation revealed a benign appearing 30mm sessile polyp in the proximal rectum 15cm from the anal margin and a 3mm ulcer in the cecum (A, B, C, D). Pathologic evaluation and immunohistochemical analysis of the cecal ulceration tissue was suggestive of a diagnosis of primary breast cancer with metastasis to the colon (E, F, G, H).The polyp in the proximal rectum was benign. The patient elected to be discharged to home and had close follow-up. The rapidly progressive nature of the patient’s presentation prevented further workup and ultimately the patient expired less than a month after diagnosis. Discussion: We present an unusual case of metastatic carcinoma of the breast to the colon and liver in an individual without a previous diagnosis of breast cancer who is treatment naïve. The accelerated time course from presentation to patient death was noteworthy. Accurate identification and differentiation between primary gastrointestinal cancer and metastatic breast cancer is paramount to proper management and treatment of the disease. This can be achieved through engaging a multidisciplinary team. This case highlights the need to maintain a high index of suspicion for colon ulcers and lesions as potential sites of metastasis of other primary malignancies such as breast cancer.Figure 1.: A 30mm sessile polyp in the proximal rectum 15cm from the anal margin (A), rectal polyp resected and retrieved (B), and 3mm ulcer in the cecum (C, D). Medium power (40x) and high power (100x) views of a H&E stained slide shows a biopsied fragment of colonic mucosa with metastatic carcinoma involving the deep mucosa and superficial submucosa. The moderately to poorly differentiated malignant epithelial cells infiltrate in nests and cords without forming clear glandular structures (E, F). Nuclear hyperchromasia is seen on higher magnification (F). Immunohistochemical staining, essential in the characterization of this tumor, supports the diagnosis of a carcinoma metastatic from the breast. CK7 shows strong, diffuse positivity, highlighting tumor cells (G). GATA3 shows scattered but strong, nuclear positivity (H). Tumor cells are negative for CK20, CDX2, and S100.