Dr. Singh on the Potential Effects of Radiation Timing in Head and Neck Cancer

Anurag Singh, MD, professor of oncology, director of radiation research, Department of Radiation Medicine, co-leader, Cell Stress and Biophysical Therapies Program, associate dean of graduate medical education, Research, Roswell Park Comprehensive Cancer Center, professor of medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, discusses the potential effects of radiation timing in head and neck cancer.

Interest has been generated regarding the potential effect of circadian rhythm on radiation therapy, Singh says. Prior data comparing outcomes and toxicities of patients treated with radiation therapy early in the morning vs late in the afternoon did not demonstrate significant differences.

However, a retrospective trial demonstrated that radiation treatment time was significantly associated with oral mucositis severity. The severity was lowest for patients treated between 8:30am and 9:30am, increased and peaked between 11:30am and 3:00pm, and decreased substantially after 3:00pm.

Although these data reflect a similar severity of oral mucositis between early morning and late afternoon treatment, they also suggest that additional research is needed to determine why patients treated with radiation therapy in the middle of the day experienced increased toxicity vs those treated in the early morning or late afternoon, Singh concludes.