Porokeratosis and cutaneous malignancy. A review.

BACKGROUND

Porokeratosis is a disorder of epidermal keratinization manifested clinically by a raised border and histologically by a cornoid lamella. While cutaneous malignancy has been reported to arise in porokeratosis, the risk remains unknown. In the past it has been associated with a history of radiation therapy.

OBJECTIVE

The purpose of this study is to estimate the frequency of cutaneous malignancy arising in porokeratosis and define those patients who are at highest risk.

METHODS

All cases in the English language literature in the last 30 years were reviewed.

RESULTS

Twenty-one (7.5%) of 281 cases reported revealed a malignancy arising within porokeratosis. Large lesions, those of long-standing duration, and the linear type were at greatest risk. Radiation therapy was an infrequently identified risk factor.

CONCLUSION

Porokeratosis is a premalignant condition, with certain groups of patients at greatest risk for malignant transformation.