Melanomas may look different from other irregular skin moles – they may be the ugly ducklings of irregular skin moles – according to a preliminary study published in Archives of Dermatology (JAMA/Archives), January issue.
The incidence of malignant melanoma continues to rise, explain the authors. If a doctor can identify a melanoma early he/she can treat the disease by removing the tumor. Malignant melanomas are more common among people who have many moles or other skin marks, especially if those marks are atypical in shape, size, or color. “The challenge for clinicians who diagnose and treat pigmented skin lesions is to distinguish between malignant melanoma and benign simulants.”
Alon Scope, M.D., of the Memorial Sloan-Kettering Cancer Center, New York, and team collected pictures of the backs of 12 individuals from a database of standardized patient images. They all had at least eight atypical moles; five of them had a confirmed melanoma. They asked 8 pigmented cell experts, 13 general dermatologists, 5 dermatology nurses, and 8 non-clinical medical staff to look at the images and try to identify those that looked different from all other atypical moles.
All 5 melanomas and only 2.1% (3 of 140) of the benign lesions were generally noticeable as different, meaning that two-thirds of the participants identified them as “ugly ducklings.” The researchers wrote “The malignant melanomas were apparent as being different to at least 85 percent of participants, whereas the agreement rate on the benign lesions perceived as being different was 76 percent at most. Four lesions were generally apparent as completely different, all four being malignant melanomas.”
The test had a sensitivity of 90% for all participants i.e. 90% of melanomas were identified as different.
Sensitivity was –
— 100% for the pigmented lesion experts
— 89% for general dermatologists
— 88% for nurses
— 85% for non-clinicians
The researchers wrote “Although the sensitivity and specificity and diagnostic accuracy of the ugly duckling sign depended on clinical expertise, the values for these parameters were good in all subgroups of participants. These preliminary findings suggest that the ugly duckling sign may prove to be a useful screening strategy for primary health care providers and even for skin self-examination.”
“The “Ugly Duckling” Sign – Agreement Between Observers”
Alon Scope, MD; Stephen W. Dusza, MPH; Allan C. Halpern, MD, MS; Harold Rabinovitz, MD; Ralph P. Braun, MD; Iris Zalaudek, MD; Giuseppe Argenziano, MD; Ashfaq A. Marghoob, MD
Arch Dermatol. 2008;144(1):58-64.
Written by – Christian Nordqvist