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The "ugly duckling" sign: agreement between observers
Alon Scope1, Stephen W Dusza, Allan C Halpern
1Dermatology Service, Memorial Sloan-Kettering Cancer Center, 160 E 53rd St, New York, NY 10022, USA.
Archives of Dermatology
|January 23, 2008
Summary
The "ugly duckling" (UD) sign effectively identifies melanomas, with all 5 melanomas recognized as different from other moles. This visual cue shows high sensitivity for melanoma detection across various medical professionals.
Area of Science:
- Dermatology
- Oncology
- Medical Imaging
Background:
- The "ugly duckling" (UD) sign refers to a mole that looks distinctly different from a patient's other moles.
- Early melanoma detection is crucial for patient outcomes.
- The visual assessment of pigmented lesions is a key component of dermatological practice.
Purpose of the Study:
- To determine if multiple observers can consistently identify the "ugly duckling" (UD) sign.
- To evaluate the sensitivity of the UD sign in detecting melanoma.
Main Methods:
- 34 participants (experts, dermatologists, nurses, nonclinicians) evaluated back images of 12 patients.
- Patients had at least 8 atypical moles; 5 had confirmed melanoma.
- A lesion was deemed a UD if perceived as different by at least two-thirds of participants.
Main Results:
- All 5 melanomas (100%) were identified as UD signs.
- Only 2.1% of benign lesions were misidentified as UD signs.
- Melanoma detection sensitivity using the UD sign was 0.9 for the overall group, with high sensitivity across all participant subgroups.
Conclusions:
- Melanomas were consistently recognized as "ugly duckling" lesions in this study.
- The UD sign demonstrates significant potential for melanoma screening.
- Further research is warranted to explore the clinical utility of the UD sign in melanoma detection.
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