Simulants of malignant melanoma

Abstract

During the recent period, dermoscopy has yielded improvement in the early disclosure of various atypical melanocytic neoplasms (AMN) of the skin. Beyond this clinical procedure, AMN histopathology remains mandatory for establishing their precise diagnosis. Of note, panels of experts in AMN merely report moderate agreement in various puzzling cases. Divergences in opinion and misdiagnosis are likely increased when histopathological criteria are not fine-tuned and when facing a diversity of AMN types. Furthermore, some AMN have been differently named in the literature including atypical Spitz tumor, metastasizing Spitz tumor, borderline and intermediate melanocytic tumor, malignant Spitz nevus, pigmented epithelioid melanocytoma or animal-type melanoma. Some acronyms have been further suggested such as MELTUMP (after melanocytic tumor of uncertain malignant potential) and STUMP (after Spitzoid melanocytic tumor of uncertain malignant potential). In this review, such AMN at the exclusion of cutaneous malignant melanoma (MM) variants, are grouped under the tentative broad heading skin melanocytoma. Such set of AMN frequently follows an indolent course, although they exhibit atypical and sometimes worrisome patterns or cytological atypia. Rare cases of skin melanocytomas progress to loco regional clusters of lesions (agminate melanocytomas), and even to regional lymph nodes. At times, the distinction between a skin melanocytoma and MM remains puzzling. However, multipronged immunohistochemistry and emerging molecular biology help profiling any malignancy risk if present.

Immunohistochemical Study of Vasculogenic Mimicry and Angiogenesis in Melanocytic Tumors of the Eye and the Periocular Area

“…Scientists have been trying to find methods in order to recognize which nevi may progress to melanoma. Modern molecular methods, including genetic markers, cytokines, and proliferation indices, are all undergoing study (25)(26)(27)(28)(29). Most of the nevi in our study were conjuctival.…”

Stardust Pattern As Evolution Of Pigmented Spitz Nevi During Childhood

“…New histological entities were introduced attempting to classify spitzoid tumours with intermediate histopathological features between Spitz naevus and spitzoid melanoma (Spitz naevus with atypia and metastasis, metastasizing Spitz tumour, atypical Spitz tumour, atypical Spitz naevus, melanocytic tumour of unknown malignant potential, melanocytoma). The worrying scenario of possible loco-regional dissemination in connection with the medico-legal liability could lead to the risk of overcalling [ 5 ].…”

Bullous Melanoma

“…[1][2][3][4][5][6] In addition to these 6 patients, rare cases of melanoma arising in patients with epidermolysis bullosa or Hailey-Hailey disease have been described, 7,8 as well as 1 case of vesiculobullous metastatic melanoma. To the best of our knowledge, only 6 cases have been reported to date in patients without a concomitant bullous skin disorder.…”