Amelanotic Melanomas Versus Pigmented Melanomas: Risk and Survival
Posted: Friday, April 5, 2019
Although amelanotic malignant melanoma is difficult to diagnose, greater clinician awareness, lower biopsy thresholds, and more patient education may be useful in improving its detection among patients with certain characteristics, concluded a study published in the JAAD–Journal of the American Academy of Dermatology. Caroline C. Kim, MD, of Harvard Medical School, Boston, and colleagues found that compared with pigmented melanoma, amelanotic malignant melanoma was associated with older age, red hair, and a history of non-melanoma skin cancer.
“Greater awareness of any suspicious amelanotic lesions in patients with these clinical factors, and a lower threshold for biopsy could lead to earlier detection,” the authors concluded.
The investigators performed a cross-sectional retrospective analysis of 933 patients with amelanotic malignant melanoma (n = 342) and pigmented malignant melanoma (n = 591) using a medical record review. These patients were treated at a specialty Pigmented Lesion Clinic and Cutaneous Oncology Program in Boston.
The findings suggested that patients with amelanotic malignant melanoma were more likely to be older, have a history of nonmelanoma skin cancer, and red hair; they also were less likely to have more than 50 nevi, a history of dysplastic nevi, or a family history of melanoma. In addition, a melanotic melanoma was more likely to be located on the head or neck and to have more aggressive pathologic features than pigmented melanoma, whereas it was less likely to be associated with a precursor nevus or regression.
Misdiagnoses were more common among patients with amelanotic melanoma than pigmented melanoma (25% vs. 12% clinically; 12% vs. 7% pathologically). Those with amelanotic melanoma also had poorer 5-year melanoma-specific survival rates (0.77 vs. 0.84, respectively).
Disclosure: The study authors reported no conflicts of interest.