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Extensive regression in pigmented skin lesions: a dangerous confounding feature
Aimilios Lallas1, Zoe Apalla, Elvira Moscarella
1State Clinic of Dermatology, Hospital of Skin and Venereal Diseases of Thessaloniki, Greece.
Dermatology Practical & Conceptual
|June 21, 2013
Summary
Spontaneous regression is common in melanomas and melanocytic nevi, but can complicate diagnosis. Dermoscopic features like white and gray-blue areas are key indicators of regression in skin lesions.
Area of Science:
- Dermatology
- Oncology
- Dermoscopy
Background:
- Spontaneous regression occurs in 10-35% of primary cutaneous melanomas.
- Regression does not guarantee a favorable prognosis, as metastatic disease can still develop.
- Dermoscopy reveals specific features like white scar-like areas and gray-blue granules associated with regression.
Observation:
- Both melanomas and melanocytic nevi can exhibit regression.
- White areas on dermoscopy suggest fibrosis-type regression.
- Gray-blue areas indicate melanosis-type regression.
Findings:
- Lichen planus-like keratosis (LPLK) shows a gray-blue granular pattern during regression.
- This pattern resembles that seen in regressed melanocytic lesions.
- Interpreting dermoscopic findings in highly regressed lesions can be challenging.
Implications:
- Accurate dermoscopic interpretation is crucial for diagnosing regressed skin lesions.
- Understanding regression patterns aids in differentiating benign from malignant lesions.
- Further research may improve diagnostic accuracy for complex regressed lesions.
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