Desmoplastic Melanoma Presenting as Primary Alopecia Neoplastica: A Report of Two Cases
July 2016
in “
Journal of Cutaneous Pathology
”
desmoplastic melanoma primary alopecia neoplastica scarring alopecias amelanotic lesion sun-damaged skin atypical spindled melanocytes collagen deposition lymph node metastasis alopecia areata lupus erythematosus lichen planopilaris S100 protein Breslow thickness immunostains SOX-10 DM scar-like alopecia S100
TLDR Two women were diagnosed with a rare melanoma that looked like hair loss but was actually a type of skin cancer.
The document from 2016 reports on two women, aged 59 and 66, who were diagnosed with desmoplastic melanoma (DM) presenting as primary alopecia neoplastica, a rare form of melanoma that is often misdiagnosed as scarring alopecias due to its similar appearance. DM typically occurs as an amelanotic lesion on sun-damaged skin and is characterized by atypical spindled melanocytes and collagen deposition. It has a higher local recurrence rate but a lower risk of lymph node metastasis than conventional melanoma. The patients' scalp lesions were initially thought to be alopecia areata, lupus erythematosus, or lichen planopilaris, but biopsies confirmed DM with S100 protein expression. One patient underwent surgery with a Breslow thickness of 8.5 mm found, while the other was lost to follow-up. The document stresses the importance of recognizing DM in the differential diagnosis of scar-like alopecia and the use of immunostains like S100 protein and SOX-10 for accurate diagnosis on small biopsies. It also discusses treatment recommendations and prognostic factors for DM.
