Polypoid melanoma and superficial spreading melanoma different subtypes in the same lesion

Abstract

Melanoma is a malignant melanocytic neoplasm with high mortality rate, and steadily and universally increasing incidence rates. Polypoid melanoma is considered an exophytic variant of the nodular subtype. The incidence of polypoid melanoma is extremely variable, most likely because of the different criteria used for its characterization. We presented a rare case of polypoid melanoma and superficial spreading melanoma in the same lesion.

Nodular Melanoma-Like Superficial Spreading Melanoma Arising from Intradermal Unna Nevus-Can Incomplete Oncogenic-senescence be Responsible for Non-hierarchical Melanomagenesis?

“…The most common clinicopathological types of MM are lentigo maligna (LM), SSM, acral lentiginous melanoma and NM [1][2][3]. SSM is the most common clinicopathological subtype and accounts for 60-70% of MM cases in Caucasians, followed by nodular subtype.…”

“…Besides these common presentations, MMs sometimes may show unusual clinical expressions. One of them is PM (or polypoid melanoma [PoM]), and this variant can be confused with other skin lesions with pedunculated or polypoid appearance including intradermal nevus, fibroepithelial polyp, or pyogenic granuloma [1,6].…”

“…Malignant Melanoma (MM) is an aggressive tumor of melanocytes, and its incidence has been increasing worldwide over recent decades [1]. It can arise from either benign melanocytic skin lesions, or melanocytes within the other regions of the body including skin, mucosa and uvea, as de nova [2].…”

Macular-appearing Nodular melanoma Arising from a Preexisting Melanocytic nevus in an Elderly patient--Can “Older Age of Nevus” be Besponsible for Unusual Morphogenesis and Melanomagenesis?

“…However, the nodular appearance can at times result from the uncommon types of MM such as polypoid or pedunculated melanoma. Such lesions can mimic benign skin lesions including intradermal nevus, fibroepithelial polyp, or pyogenic granuloma (1,7,8). On the other hand, SSM usually begins as a smooth or slightly elevated pigmented spot.…”

“…MM is the most malignant melanocytic tumor, and it is responsible for approximately 95% of deaths caused by cutaneous cancer (1)(2)(3). The lesions are usually located on the trunk in males, while they more frequently occur in the lower extremities in females (3,4).…”