What is the likely diagnosis for a pigmented lesion that has enlarged and changed color over a period of three months?

The diagnosis of a pigmented lesion that has enlarged and changed color over a three-month period strongly suggests a nevocellular nevus, commonly known as a mole. Nevocellular nevi are typically stable benign growths formed from melanocytes and can exhibit various colors and sizes. However, when such a lesion undergoes changes in size, shape, or color, it raises concern for potential malignancy or dysplastic changes, signaling the need for careful evaluation.

In a clinical context, the observation that a pigmented lesion has not only changed color but also enlarged within a relatively short time frame is a hallmark characteristic to consider. While benign nevus can sometimes grow slightly or change color with sun exposure, significant alterations after a brief period may indicate a progression toward a more serious condition such as melanoma. Therefore, the emphasis on recent changes in the lesion heightens the suspicion for atypical or dysplastic features that are typically assessed during dermatologic evaluations.

This highlights why monitoring pigmented lesions is crucial—any rapid changes warrant further investigation to rule out malignancy, guiding appropriate management and intervention.