Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations Diffuse Melanosis Cutis Under Immuno and Targeted Therapy Cussigh 2025 JEADV Clinical Practice Wiley Online Library 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 Intracranial metastatic melanoma Radiology Reference Article Radiopaedia.org Metastatic Melanoma: Symptoms, Stages, Treatment Metastatic Malignant Melanoma