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https://doi.org/10.4081/dr.2025.10415

Primary malignant melanoma with pseudovascular morphology: a diagnostic pitfall

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Published: 19 November 2025
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Diagnostic pitfall, immunohistochemistry, malignant melanoma, next-generation sequencing, pseudovascular morphology

Authors

Monia Di Prete
https://orcid.org/0000-0002-3881-8540
Dermatopathology Research Unit, San Gallicano Dermatological Institute IRCCS, Rome, Italy.
Paola Pasquini
https://orcid.org/0009-0003-2788-6024
Dermatopathology Research Unit, San Gallicano Dermatological Institute IRCCS, Rome, Italy.
Elisa Melucci
Department of Pathology, Regina Elena National Cancer Institute IRCCS, Rome, Italy.
Viviana Lora
Clinical Dermatology, San Gallicano Dermatological Institute IRCCS, Rome, Italy.
Carlo Cota
carlo.cota@ifo.it
Dermatopathology Research Unit, San Gallicano Dermatological Institute IRCCS, Rome, Italy.

Melanoma is a neoplasm with a heterogeneous clinical presentation and several histopathological variants have been described. Although histopathological evaluation remains the diagnostic gold standard, unusual morphology of some melanomas can lead to erroneous pathologic misinterpretation, as they can be confused with other non-melanocytic tumors. Here, we present a case of nodular melanoma with pseudovascular morphology characterized by uncommon empty branching slit-like spaces, reminiscent of rete testis vessels, for which we suggest the name of retiform melanoma to distinguish it from angiomatoid melanoma. Immunohistochemical analysis and ancillary molecular tests helped us characterize this neoplasm, underscoring the need for clinical-morphological-molecular correlation for the correct diagnosis of unusual cases.

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How to Cite



1.
Di Prete M, Pasquini P, Melucci E, Lora V, Cota C. Primary malignant melanoma with pseudovascular morphology: a diagnostic pitfall. Dermatol Reports [Internet]. 2025 Nov. 19 [cited 2026 Apr. 18];. Available from: https://journals.pagepress.net/dr/article/view/10415
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