Desmoplastic melanoma: a rare variant with challenging diagnosis

Abstract

Desmoplastic melanoma, a distinct and uncommon variant, is characterized as an invasive lesion with proliferation of fusiform melanocytes in the dermis and subcutaneous tissue, associated with varying patterns of desmoplasia. Neurotropism and neural differentiation may occur. The clinical presentation is variable and nonspecific, easily confused with other fibrous neoplasms. The disease is locally aggressive and shows lower metastasis rates than other types of melanoma. Histopathology may be insufficient, requiring positive immunohistochemistry for S-100 protein and other antigens of melanocytic differentiation. Because desmoplastic melanoma represents a true clinical, dermoscopic, and histopathological diagnostic challenge, a case of invasive desmoplastic melanoma is reported, affecting a photoexposed area in an elderly woman after histological revisions and an initial diagnosis of fibroma.

Pigmented melanoma cell migration study on murine syngeneic B16F10 melanoma cells or tissue transplantation models

“…Melanomafibroblast interactions can be considered the cause of these morphological changes, knowing that melanoma cells can recruit and activate stromal fibroblasts which in turn provide the structural and chemical support for melanoma cell migration (33,34,35). The lack of pigmented melanoma cells in the lumen of newly formed vessels could explain the local aggressiveness and low metastatic rate observed in these types of melanoma (36).…”

Cutaneous Melanoma: A Review of Multifactorial Pathogenesis, Immunohistochemistry, and Emerging Biomarkers for Early Detection and Management

“…Various melanocytic markers such as S100, HMB45, Melan A, tyrosinase, MITF, and SOX10 can aid in the detection and subtyping of melanoma [58][59][60]. The S100 marker stands out for its high sensitivity for melanomas of all subtypes, including desmoplastic melanoma [60,61]. However, it is important to note that while S100 demonstrates high sensitivity, its specificity is limited, given that it is also expressed in a range of other malignancies and normal cellular components, such as dendritic cells, certain macrophages, and Schwann cells in lymph nodes [62,63].…”