ReportsAmelanotic melanoma: The great masquerader☆
Section snippets
Case 1
This 52-year-old white man with no previous history of skin cancer presented with an “unusual spot” on the top of his left shoulder. The lesion was asymptomatic. The patient had seen a physician who rendered a diagnosis of basal cell carcinoma and then performed a small incisional shave biopsy that showed melanoma in situ. He was self-referred for further evaluation. On physical examination he had a few atypical nevi of his trunk. The shoulder lesion consisted of a 1.3 × 2.0-cm slightly raised
DISCUSSION
The clinical term amelanotic implies that the tumor lacks any pigmentation on visual inspection. A review of the literature suggests that the term is often used more loosely to include tumors only partially devoid of pigment. According to Guiliano, Cochran, and Morton,6 most tumors have pigmentation involving the adjacent skin; truly amelanotic lesions are rare.
Any clinical subtype of cutaneous melanoma may be amelanotic, although it is more common for this to occur in subungual tumors and in
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Cited by (167)
Cells to Surgery Quiz: January 2022
2022, Journal of Investigative DermatologyPlantar Melanoma: An Investigation of Its Incidence
2021, Clinics in Podiatric Medicine and SurgeryCitation Excerpt :The misdiagnosis rate of all forms of acral melanoma has been cited as between 25% and 36%; however, this may be greater for acral amelanotic melanomas. Amelanotic melanoma constitutes 2% to 8% of all melanomas, but approximately 7% of amelanotic melanomas occurs on the plantar aspect of the foot.19 These lesions may be painless to the patient and can at times resemble a diabetic foot ulcer.20
Melanoma of the Hands and Feet (With Reconstruction)
2021, Clinics in Plastic SurgeryCitation Excerpt :Moreover, the appearance of amelanotic melanomas varies and can mimic benign and malignant conditions including hemangioma, basal cell carcinoma, squamous cell carcinoma, pyogenic granuloma, Merkel cell carcinoma, and others.24,25 The importance of improving detection of amelanotic melanoma is highlighted by the fact that these lesions present with thicker Breslow thickness, higher mitotic rate, more frequent ulceration, higher tumor stage, and lower survival than pigmented melanomas.23,25 Classically, amelanotic melanoma distribution is associated with sun-exposed areas including the dorsal aspect of the hand.23
Cells to Surgery Quiz: April 2021
2021, Journal of Investigative DermatologyManagement of Noncutaneous Melanomas
2020, Surgical Oncology Clinics of North AmericaCitation Excerpt :Overall prognosis is poor for all mucosal melanomas. Patients are more likely to present with advanced disease compared with cutaneous melanoma, which may be caused by lack of early symptoms and high rates of amelanosis (25%–70%) compared with cutaneous melanoma (1.8%–8%),86,87 which adds to the difficulty in distinguishing melanoma from other more common, benign diseases. Surgical management has moved toward wide local excision (when feasible) instead of more radical procedures.
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