Intestinal metastasis of malignant melanoma of unknown primary localization

Abstract

Malignant melanoma (MM) has been shown to metastasize with relative affinity to the gastro-intestinal (GI) tract, especially through the small intestine, mostly within, but also later than the first 5 years after initial diagnosis. MM appears to less often originate in the GI tract. Surgical excision is reported to be safe and capable of improving oncological outcomes in the absence of other metastatic disease. We hereby report the case of a patient without a history of MM presenting in our clinic with severe anemia due to a tumor located in the small bowel diagnosed on abdominal tomography. Surgery consisted in a radical resection of the affected small bowel segment. Pathological examination revealed a MM metastasis to the jejunum. On further investigation of the patient, a cutaneous lesion suggestive of MM was identified on his right upper limb, which was excised, and the patient has been referred to the multidisciplinary team for initiation of adjuvant chemotherapy. Further follow-up is required due to MM’s propensity for multiple metastases. This case emphasizes the fact that in a patient diagnosed with an intestinal tumor a thorough clinical examination should be performed, as one of the possible differential diagnosis of intestinal tumors is the metastatic localization of a cutaneous MM.