Multiple synchronous anorectal melanomas with different colors: A case report

Figure 4 Histologic illustration of the four lesions in this case (HE staining, 10×). A: Pedunculated mass located at the anal canal level. Although this lesion appeared unpigmented via visualization, scattered round atypical pigmented cells were found microscopically; B: The sessile mass 3 cm above the dentate line showed densely distributed pigmented cells; C and D: Two mucosal melanic zones were analyzed. Infiltration of atypical pigmented cells was found distributed in the mucosal and submucosal layers.