This is a very rare case of metastatic oral mucosal melanoma to the colon with an unusual presentation mimicking melanosis coli. The colonoscopy findings show no mass effect but multiple hyperpigmented lesions Metastatic Malignant Melanoma Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations Melanotic schwannoma mimicking metastatic pigmented melanoma: a pitfall in cytological diagnosis Metastatic Melanoma: Symptoms, Stages, Treatment Intracranial metastatic melanoma Radiology Reference Article Radiopaedia.org