Metastatic Melanoma Presenting As Small Bowel Obstruction.

Metastatic melanoma to the gastrointestinal (GI) system is a known, though overall rare, phenomenon. Typically, symptomatic presentations from GI metastases are uncommon and often nonspecific, contributing to delayed diagnosis. We present the case of a male patient with a history of cutaneous melanoma treated with wide local excision one and a half years earlier, who presents to the emergency department with presyncope, acute nausea, vomiting, and melena. Initial workup revealed a five-point hemoglobin drop. Computed tomography (CT) of the abdomen and pelvis showed a high-grade small bowel obstruction with a soft tissue mass at the transition point. The patient underwent a diagnostic laparoscopy, small bowel resection, and lymph node dissection. Histopathology and immunohistochemical markers confirmed the diagnosis of malignant melanoma, which, along with the patient's history of cutaneous melanoma, favored a metastatic etiology. This case demonstrates the need to maintain a high index of suspicion for metastatic melanoma in patients with a prior history of cutaneous melanoma, especially for those presenting with bowel obstruction or obscure GI symptoms. Surgical resection is the mainstay of therapy and can be both diagnostic and therapeutic.