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 Pathology Outlines Melanotic macule Pigmented Lesions of the Oral Mucosa Pocket Dentistry Mucosal Melanotic Macule Springer Nature Link Pathology Outlines Pigmented lesions vulva Melaninassociated pigmented lesions of the oral mucosa: presentation, differential diagnosis, and treatment Mller 2010 Dermatologic Therapy Wiley Online Library