INTRODUCTION: Melanoma presenting in the gastrointestinal tract is commonly due to metastasis from a primary cutaneous or ocular lesion. There have been a few case reports of primary GI melanoma which is most commonly seen in the rectum and anus. We report a case of a 77 year old man who presented with GI bleeding and was found to have a primary small bowel melanoma. CASE DESCRIPTION/METHODS: A 77-year-old male presented with generalized weakness and a remote history of melena for the past week. Physical exam was unremarkable with no palpable masses or abdominal tenderness. Labs were significant for iron deficiency anemia with a hemoglobin of 8.9 from 13.1 and a ferritin of 14 ng/ml. Patient underwent bidirectional endoscopy which showed no clear source for iron deficiency anemia. A capsule endoscopy was performed, and a mass with overlying ulcerated mucosa was seen in the small bowel (Figure 1). Subsequent computed tomographic enterography demonstrated a 3.3 cm soft tissue mass in the jejunum (Figure 2). As the mass was unable to be reached endoscopically, the patient underwent laparoscopic removal of the mass, and pathology was most consistent with malignant melanoma. Histology showed solid nests of epithelioid cells with brisk mitotic activity, and immunohistochemistry staining was positive for SOX-10 (Figure 3), a marker of melanocyte differentiation. The patient underwent a skin exam showing no evidence of a cutaneous primary melanoma, and a fundoscopic exam showed no evidence of ocular melanoma. A PET scan did not identify an alternative site of primary malignancy or any other sites concerning for metastatic disease. As the patient had a solitary lesion in the small bowel without evidence of an alternative primary melanoma, the final diagnosis was primary malignant melanoma of the jejunum. At one year follow up, patient did not have any recurrence noted on imaging. DISCUSSION: While melanoma is the most common tumor to metastasize to the GI tract, small intestinal primary melanoma is extremely rare making up 2.3% of primary GI melanomas. In all cases where melanoma is found in the GI tract, a comprehensive evaluation for additional metastatic lesions and alternative primary site with a skin exam, fundoscopic exam and PET scan is indicated. Primary GI melanoma is a rare clinical entity with nonspecific symptoms that requires a high index of suspicion and a thorough workup for a primary source when diagnosed.Figure 1.: Mass with overlying ulcerated mucosa in the small bowel on capsule endoscopy.Figure 2.: 3.3 cm soft tissue mass in the jejunum on computed tomographic enterography.Figure 3.: Immunohistochemistry staining of jejunal mass was positive for SOX-10, a marker of melanocyte differentiation.