Malignant melanoma arising in a seborrheic keratosis.

We report a case of malignant melanoma associated with seborrheic keratosis. This has been reported rarely in the literature, with disagreement regarding whether it is coincidental or whether malignant transformation occurs. Because seborrheic keratoses are common and association with malignant melanoma is very rare, we conclude that the association is coincidental. However, because of the association of other malignancies, a biopsy of any suspect or changing seborrheic keratosis is essential.