Recurrent basal cell carcinoma treated with radiation therapy

Abstract

A retrospective study was performed of 61 recurrent basal cell carcinomas treated with radiation therapy between 1974 and 1990 at the University of Arizona College of Medicine or at Southwestern Radiation Oncology, Tucson, Arizona. The median length of follow-up was 57 months. Applying the American Joint Committee on Cancer staging system to these recurrent tumors, 36 were stage I, 19 were stage II, five were stage III, and one was stage IV. Kaplan-Meier methods were used to estimate the 5-year complete remission rates. The Mantel-Haenszel Test and the Cox Proportional Hazards Model were used to determine if tumor size, stage, histologic subtype, anatomic site, age, sex, dose, number of radiation therapy treatments, length of time over which the radiation therapy was administered, or type of radiation beam used (orthovoltage x-rays vs megavoltage electrons) affected the 5-year complete remission rates. Only tumor size and stage had a statistically significant effect on the complete remission rates. The Kaplan-Meier estimates of the 5-year complete remission rates for 0.5- to 1.0-cm tumors vs tumors larger than 1.0 cm were 96% (95% confidence interval, 88% to 100%) and 81% (95% confidence interval, 64% to 99%), respectively. The Kaplan-Meier estimates of the 5-year complete remission rates for stage I/II tumors vs stage III/IV tumors were 93% (95% confidence interval, 85% to 100%) and 42% (95% confidence interval, 8% to 84%), respectively. Functional and cosmetic results were frequently good to excellent at 5 years. Soft-tissue necrosis developed in two of 61 cases, and was successfully managed in both. This article, combined with a review of the literature, suggests that radiation therapy is an effective method of treating recurrent basal cell carcinomas.