Use of the ugly duckling (UD) sign for melanoma recognition has been shown to significantly improve accuracy and specificity in disease detection, leading to decreased morbidity and mortality, according to the results of a study published in the Journal of the American Academy of Dermatology.1

The investigators sought to compare the sensitivity, specificity, and accuracy of melanoma recognition with use of the ABCD rule (A=asymmetry; B=border irregularity; C=color variegation; D=diameter >6 mm) vs use of the UD sign. The ABCD rule, which was developed in 1985 and revised in 2005 to include an “E,” which stands for Evolution (ie, ABCDE; the “E” portion was not tested in this study), is considered a cornerstone of melanoma recognition among both physicians and laypersons.2 The UD sign, a recently developed strategy for melanoma recognition, is the process of comparing cutaneous lesions on a patient and identifying an obviously different lesion (the UD). The UD lesion is usually considered to be suspicious for malignancy.

In this study, a total of 101 participants were randomly assigned into either the ABCD arm (n=51) or the UD arm (n=50). Individuals in each group received an educational tutorial on their respective teaching method for melanoma detection. Although more participants were familiar with the ABCD rule than with the UD sign (23.78% vs 4.0%, respectively), the majority (72.2%) were unfamiliar with both strategies.

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The sensitivity of recognition of malignant melanoma with both methods was high (100% in the UD group vs 99% in the ABCD group). However, the specificity for malignant melanoma recognition was significantly higher in the UD arm than in the ABCD arm (88.3% vs 57.4%, respectively; P =.02). Moreover, the accuracy of melanoma recognition was significantly higher in the UD group compared with the ABCD group (90.9% vs 66.7%, respectively; P =.02).

Based on these findings, the investigators recommend inclusion of the UD sign, in addition to the traditional ABCDE rule, in patient education campaigns, thus allowing for improved melanoma recognition in the general population.

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  1. Ilyas M, Costello CM, Zhang N, Sharma A. The role of the ugly duckling sign in patient education [published online September 27, 2017]. J Am Acad Dermatol. doi: 10.1016/j.jaad.2017.06.152
  2. Friedman RJ, Rigel DS, Kopf AW. Early detection of malignant melanoma: the role of physician examination and self-examination of the skin. CA Cancer J Clin. 1985;35(3):130-151.