Melanoma skin cancer sign: Border that is irregular

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A normal mole and a mole with a ragged, notched border

Melanoma is the most serious type of skin cancer. The most important warning sign of melanoma is a change in the size, shape, or color of a mole or other skin growth, such as a birthmark.

  • Border irregularity is one thing to watch for. Call your doctor if any skin growth has developed ragged, notched, or blurred edges.

Current as of: March 1, 2023

Author: Healthwise Staff
Medical Review:
Kathleen Romito MD - Family Medicine
Adam Husney MD - Family Medicine
Amy McMichael MD - Dermatology

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