Thyroid Dysfunction Related to Radiation Dose in Head and Neck Cancer
Radiation dose appears to affect thyroid dysfunction in patients with head and neck cancer.
HealthDay News -- For patients with head and neck cancer receiving radiotherapy, thyroid dysfunction is a dose-related complication, with increased risk for female sex and concurrent chemotherapy, according to a study published in Head & Neck.
Stella Ling, MD, MPH, from The Ohio State University in Columbus, and colleagues reviewed records of 102 patients, who received radiation therapyfrom 2008 to 2010, to assess thyroid function. The authors grouped abnormalities as none, transient, or permanent; and overt or subclinical.
The researchers found that the incidence of any thyroid abnormality was 39.2% at a median follow-up of 33.5 months (women vs men: 50% vs 35%). Overall, 24.5% had permanent dysfunction, with higher incidence for women vs men (42.9% vs 17.6%; P =.0081). There was a strong correlation for permanent abnormalities with the half maximal inhibitory dose (P =.0275). There was also a correlation between the volume of the thyroid receiving 50 Gy and thyroid dysfunction after radiotherapy (P =.0316). Permanent dysfunction was increased with concurrent chemotherapy (P =.0008).
"Radiation-induced hypothyroidism is clearly a dose-related complication of head and neck radiotherapy," the researchers wrote. "Female sex and use of concurrent chemotherapy predict for an increased risk of radiotherapy-related thyroid dysfunction."
- Ling S, Bhatt AD, Brown NV, et al. Correlative study of dose to thyroid and incidence of subsequent dysfunction after head and neck radiation [published online December 1, 2016]. Head Neck. doi:10.1002/hed.24643.