Anal melanoma with neuroendocrine differentiation: report of a case.
Melanoma of the anal cavity is an uncommon malignant tumor with an aggressive clinical behavior. The presence of nonmelanocytic cell or tissue components, designated as divergent differentiation, is an unusual but well-documented phenomenon in melanoma. We experienced a rare case of amelanotic melanoma with neuroendocrine differentiation of the anal canal, occurring in a 68-year old woman. This tumor was characterized by a clear-cut radial growth phase and an invasive component composed of a diffuse small cells population positive for neuroendocrine markers with a focal but convincing co-expression of S100 protein. To the best of our knowledge, this represents the first case of neuroendocrine differentiation in a primary melanoma of the anal cavity. Although anal melanoma with neuroendocrine differentiation is exceptional, clinical practitioners should be aware of its possibility at this site.
University of Naples Federico II, Naples, Italy.
Gennaro
G
Ilardi
University of Naples Federico II, Naples, Italy.
Danila
D
Caroppo
University of Naples Federico II, Naples, Italy.
Silvia
S
Varricchio
Regional Oncologic Hospital, CROB, Rionero in Vulture, Potenza, Italy.
Giulia
G
Vita
University of Naples Federico II, Naples, Italy.
Pierpaolo
P
Di Lorenzo
University of Naples Federico II, Naples, Italy.
Luigi
L
Insabato
University of Naples Federico II, Naples, Italy.
Gaetano
G
De Rosa
University of Naples Federico II, Naples, Italy massimo.mascolo@unina.it.
Massimo
M
Mascolo
D000368:Aged; D001005:Anus Neoplasms / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000032:analysis; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008545:Melanoma / Q000473:pathology*; D055099:Neuroendocrine Cells / Q000473:pathology*
D014408:Biomarkers, Tumor
amelanotic melanoma; anal cavity; immunohistochemistry; neuroendocrine differentiation