Fluorouracil paste treatment of thin basal cell carcinomas.

Treatment of thin (superficial) basal cell carcinomas (BCCs) with topical fluorouracil is widely accepted despite the absence of published five-year cure rates. The published short-term data disclose treatment failure rates substantially higher than other modalities. In trials to improve and standardize topical fluorouracil therapy, thin BCCs were treated with 25% fluorouracil in petrolatum under occlusion for three weeks using weekly dressing changes. Of 44 thin BCCs treated only with 25% fluorouracil under occlusion for three weeks, the five-year cumulative recurrence rate was 21%. In a second series of 244 BCCs, light curettage preceded the 25% fluorouracil treatment to yield a five-year cumulative recurrence rate of 6%. Cosmetic results were good to excellent in more than 80% of both series. While fluorouracil by itself is not a satisfactory treatment for thin BCC, when combined with light curettage, topical fluorouracil therapy is capable of cure rates competitive with other modalities.