Phase I study of topical epigallocatechin-3-gallate (EGCG) in patients with breast cancer receiving adjuvant radiotherapy

Objective: The purpose of this study was to investigate the safety, tolerability and preliminary effectiveness of topical epigallocatechin-3-gallate (EGCG) for radiation dermatitis in patients with breast cancer receiving adjuvant radiotherapy. Methods: Patients with breast cancer who received radiotherapy to the chest wall after mastectomy were enrolled. EGCG solution was sprayed to the radiation field from the initiation of Grade 1 radiation dermatitis until 2 weeks after completion of radiotherapy. EGCG concentration escalated from 40 to 660 mu mol l(-1) in 7 levels with 3-6 patients in each level. EGCG toxicity was graded using the NCI (National Cancer Institute Common Terminology Criteria for Adverse Events) v. 3.0. Any adverse event >Grade 1 attributed to EGCG was considered dose-limiting toxicity. The maximum tolerated dose was defined as the dose level that induced dose-limiting toxicity in more than one-third of patients at a given cohort. Radiation dermatitis was recorded weekly by the Radiation Therapy Oncology Group scoring and patient-reported symptoms. Results: From March 2012 to August 2013, 24 patients were enrolled. Acute skin redness was observed in 1 patient and considered to be associated with the EGCG treatment at 140 mu mol l(-1) level. Three more patients were enrolled at this level and did not experience toxicity to EGCG. The dose escalation stopped at 660 mu mol l(-1). No other reported acute toxicity was associated with EGCG. Grade 2 radiation dermatitis was observed in eight patients during or after radiotherapy, but all decreased to Grade 1 after EGCG treatments. Patient-reported symptom scores were significantly decreased at 2 weeks after the end of radiotherapy in pain, burning, itching and tenderness, p < 0.05. Conclusion: The topical administration of EGCG was well tolerated and the maximum tolerated dose was not found. EGCG may be effective in treating radiation dermatitis with preliminary investigation. Advances in knowledge: EGCG solution seemed to be feasible for treating radiation dermatitis in patients with breast cancer after mastectomy. It should be tested as a way to reduce radiation-induced normal tissue toxicity and complications in future years.