Standard adjuvant treatment for HER2-positive breast cancer patients, following primary surgery for their cancer, is Trastuzumab (Herceptin)--typically used in combination with chemotherapy. However, a new study by researchers at Fox Chase Cancer Center reports that it may be safe to treat these patients with both Trastuzumab and adjuvant radiation therapy. The study will be presented today at the annual meeting of the American Society for Radiation Oncology (ASTRO).
"Our study evaluated the skin toxicity and early cardiac toxicity of concurrent Trastuzumab and radiation therapy treatment in the adjuvant setting," says Penny Anderson, M.D., radiation oncologist at Fox Chase and lead author on the study. "We found that there was an extremely low rate of acute radiation dermatitis and cardiac toxicity in patients who received this type of treatment."
The study followed 85 breast cancer patients who received adjuvant Trastuzumab while also receiving a course of adjuvant radiation therapy, as well as 85 breast cancer patients who only received adjuvant radiation therapy. Acute dermatitis was grade 2 in 15% and grade 3 in 2% of the patients receiving concurrent treatment, likewise grade 2 and grade 3 dermatitis was observed in 14% and 2 % of patients only receiving radiation therapy--there was only one patient who developed a grade > 2. There were no differences in cardiac toxicity between the two groups.
"The results of this study show that it is safe to use both Trastuzumab and radiation therapy in an adjuvant setting, when clinically indicated," adds Anderson. "We would like to see longer follow-up to evaluate the potential differences in late cardiac toxicity."