Ren M, et al. - Researchers described the clinical presentations, histopathology, and prognosis of 60 cases in China to study the clinicopathologic features and prognostic factors of primary anorectal melanoma. In this investigation, patients' age ranged from 17 to 86 years with a female-to-male ratio of 2.33:1. Multivariate analysis showed that age> 70 years and tumor invasion beyond deep muscular layer/sphincter ani externus were independent poor prognostic factors. They concluded that anorectal melanoma is a rare and lethal malignant neoplasm with morphological diversity as the largest single-institution study of anorectal melanoma in an Asian population.