Melanosis coli Wikipedia Brown spots, especially on the lips, can be alarming to some. In some instances it can indicate rare oral mucosal melanoma, however in this case it was a non cancerous labial melanotic macule. COM March 2009 Diagnosis UW School of Dentistry Labial or Oral Melanotic Macule Benign, asymptomatic, and often underdiagnosed. Swipe to learn how to recognize, diagnose, and manage this simple yet important lesion! #thebasicdentist #rguhs #kuhs #tnmgrmu #OralPathology #MelanoticMacule #DentalFacts Labial melanotic macule Abuse of laxatives and melanosis coli