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Persistent perpendicular pigmentation: a peculiar but specific type of persistent nevus
Julia L Accetta1, Melissa M Helm, Lin Lin
1Tulane University School of Medicine, New Orleans, Louisiana. jaccetta@tulane.edu.
Dermatology Online Journal
|April 11, 2018
Summary
Persistent nevi, often mistaken for melanoma, are benign growths. Their unique pigmentation pattern confined to surgical scars is a key diagnostic clue.
Area of Science:
- Dermatology
- Pathology
Background:
- Persistent nevi are common in clinical and dermatopathology practice.
- These lesions can clinically and microscopically resemble melanoma but are benign.
Observation:
- Persistent nevi may display asymmetry and irregular features, raising concern for melanoma.
- Pigment restriction to the surgical scar is a crucial diagnostic indicator.
- Linear patterns along skin tension lines (Langer lines) can be observed in some persistent nevi.
Findings:
- The study reviews clinical and histologic features of persistent nevi.
- A case with striking perpendicular pigmentation confined to a scar is presented.
- This pattern is reassuring and aids in diagnosis.
Implications:
- Understanding the characteristic features of persistent nevi can prevent misdiagnosis of melanoma.
- Recognition of scar-confined pigmentation is vital for accurate dermatopathological assessment.
- This knowledge aids clinicians in reassuring patients about benign lesion behavior.
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