Sparing the contralateral submandibular gland with low doses of radiation therapy appeared safe and effective among patients with locally advanced head and neck cancers, according to study results presented at the Multidisciplinary Head and Neck Cancer Symposium.
“Historically … there has been hesitation to spare the submandibular gland from radiation because there are lymph nodes near the gland that also end up not getting treated,” researcher Tyler Robin, PhD, an MD candidate at the University of Colorado School of Medicine, said in a press release. “While this seems worrisome because head and neck cancer spreads through the lymph nodes, it is well established that the risk of cancer involvement in the lymph nodes near the submandibular gland is exceedingly low, yet the benefit of sparing the gland for a patient’s quality of life is high.”
Robin and colleagues evaluated data from 71 patients who underwent contralateral submandibular gland-sparing radiation therapy at the University of Colorado Cancer Center or Memorial Sloan-Kettering Cancer Center. The median age of patients was 55 years. About half of patients were current or former smokers, and half were never smokers.
Nearly 50% of patients had lesions involving the base of the tongue. About 80% of patients had N2b or greater disease, and 90% of patients had overall stage IV disease.
Researchers classified contralateral submandibular gland sparing as mean radiation doses to the contralateral submandibular gland of ≤39 Gy. The mean radiation dose to the contralateral submandibular gland of all patients in the study was 33.04 Gy.
Median follow-up was 27.3 months. At this time, no patients experienced disease recurrences in the contralateral level Ib lymph nodes.
“It is important to consider treatment side effects alongside treatment benefit, and overall, our goal is to decrease side effects associated with radiation treatment without undertreating a patient’s cancer,” Robin said. “With modern advances in radiation therapy, it is possible to eloquently treat cancers while avoiding surrounding normal tissues. Our study is a prime example of how we can safely spare normal tissues in appropriate patients in order to decrease treatment side effects.”
* This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.