P2488 - Melanoma Metastasis Madness: A Rare Case of Melanoma Metastasis to the Stomach, Duodenum, and Colon

Abdulazeez Swaiti, MD¹, Jinye Liu, DO², Christina Santana, MD², Stephanie Ibarra Lepe, MD², Christin Wilkinson, MD¹, Saeed Graham, MD¹, Ahmed Hebishy, MD², Amy Chang, MD², Matthew Tugman, BA³, Michelle Cooley, BS³, Catherine Gray, BS³, Hassam Ali, MD¹, Zarak Khan, MD⁴, Rahul Pamarthy, MD¹, Danielle Hoo-Fatt, MD^4
1East Carolina University, Greenville, NC; ²East Carolina University Medical Center, Greenville, NC; ³East Carolina University Brody School of Medicine, Greenville, NC; ⁴East Carolina Gastroenterology, Greenville, NC

Introduction: Melanoma is the deadliest form of skin cancer and is rapidly increasing worldwide. After metastasis, the 10-year survival rate for patients with metastatic melanoma is less than 10%. Metastasis commonly affects the lungs, liver, bones, and brain. Gastric and intestinal involvement are less common and are not frequently reported. Common symptoms of gastrointestinal (GI) involvement include abdominal pain, constipation, anemia, hematochezia, melena, and weight loss. To summarize, GI metastasis constitutes only around 1-3% of all malignant melanoma. Once metastasis is found prognosis becomes poor and survival rates significantly decrease. We present a rare case of symptomatic metastasis of melanoma to a patient’s stomach and intestines.

Case Description/Methods: An 84-year-old male presented with fatigue, loss of appetite, and melena. He had been experiencing these symptoms for two months prior to admission. His medical history was significant for previous sigmoid colonic stricture status post partial colectomy, metastatic melanoma on nivolumab, chronic anemia, and failure to thrive. His hemoglobin continued to drop while prepping for upper endoscopy (EGD) and colonoscopy, requiring two units of packed red blood cells. EGD revealed localized mucosal changes characteristic of melanocytic metastasis in the gastric fundus, duodenal bulb, and in the second portion of the duodenum. His colonoscopy revealed two ulcerated large masses in the descending colon and an ulcerated small mass in the ascending colon. All masses were dark brown in color and were biopsied with cold forceps. Pathologic examination revealed the patient had metastatic melanoma in his stomach, duodenum, and colon.

Discussion: Melanocytes are derived from the neural crest, as are the cells in the GI tract which is why metastatic melanoma can be seen in the GI system. GI metastasis of melanoma presents similarly to other GI tumors with nonspecific symptoms such as abdominal pain, constipation, obstruction, hematochezia, melena, and weight loss. On endoscopic evaluation, lesions may appear as intraluminal masses, mesenteric implants, ulcerating or diffusely infiltrating pigmented or amelanotic regions. This case highlights the clinical relevance of metastatic melanoma lesions to the GI tract and reinforces the importance of maintaining a high index of suspicion, especially in patients with a known history of melanoma.



Disclosures:


Abdulazeez Swaiti, MD¹, Jinye Liu, DO², Christina Santana, MD², Stephanie Ibarra Lepe, MD², Christin Wilkinson, MD¹, Saeed Graham, MD¹, Ahmed Hebishy, MD², Amy Chang, MD², Matthew Tugman, BA³, Michelle Cooley, BS³, Catherine Gray, BS³, Hassam Ali, MD¹, Zarak Khan, MD⁴, Rahul Pamarthy, MD¹, Danielle Hoo-Fatt, MD⁴. P2488 - Melanoma Metastasis Madness: A Rare Case of Melanoma Metastasis to the Stomach, Duodenum, and Colon, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.