Topical Application of Sulforaphane-containing Broccoli Sprout Extracts on Radiation Dermatitis

Overview

The investigators plan to investigate the protective effects of topical sulforaphane-containing broccoli-sprout extracts (BSE) on radiation-induced dermatitis in women undergoing external-beam radiation therapy for breast cancer. Topical sulforaphane induces phase 2 enzymes that are protective against oxidants, electrophiles, and inflammation (Talalay and Fahey, 2001) - all of which are generated by both ultraviolet and ionizing radiation. Previous work from the investigators' group demonstrated that sulforaphane treatment protects against ultraviolet radiation-induced erythema of human skin (IRB protocol NA\_00004897; Talalay et al. 2007). This investigation will extend the investigators' previous work by employing ionizing rather than ultraviolet radiation. The investigators propose a two part sequential protocol (Study A and Study B). Both studies will involve women with breast cancer who have undergone lumpectomy and are scheduled for adjuvant external beam radiation treatment. In study A, the investigators will validate their technique for measurement of skin erythema using a device called a chromometer; no active agent will be applied (up to 6 women). Study B will follow completion of Study A. Study B will involve the application of broccoli sprout extracts (BSE) or vehicle alone to determine if sulforaphane can reduce radiation-induced erythema (27 women). Four adjacent, 1.5-cm diameter areas-of-interest on the affected breast will be located by means of an adhesive vinyl template which can be accurately and repeatedly placed at the same position. Two of the four areas will be treated with BSE (active agent) and two with vehicle (inactive control). BSE will be applied on three days weekly throughout the 5-week period of whole breast radiation. Erythema will be noninvasively quantified by measuring the red-reflectance of the skin with a chromometer up to three times weekly throughout treatment. A total of 33 patients are to be enrolled. The investigators' objective is to determine and quantify the effect of topical BSE on radiation-induced skin erythema. This study will employ standard, clinically-accepted radiation doses and techniques that are safe and well tolerated. The safety and tolerability of both oral and topical broccoli sprout preparations is well established; no safety concerns have been noted. (Shapiro et al. 2006; Dinkova-Kostova et al. 2007).