This article is more than 5 years old. Information may no longer be current.
History of radiation exposure in DTC improves overall survival
Click Here to Manage Email Alerts
Outcomes in differentiated thyroid cancer, or DTC, do not significantly differ between patients with a history of radiation exposure and those without, but a history of radiation exposure may improve overall survival, according to study findings.
“Over the past 20 years, the incidence of DTC has skyrocketed,” the researchers wrote. “Paralleling this rise has been an enormous increase in the use of medical radiation. As radiation is a major risk factor for DTC, these observations have led some investigators to suggest that increased use of medical radiation has contributed significantly to the burgeoning incidence of DTC. Little is known, however, about the effect of medical radiation on outcomes for DTC.”
In the retrospective review, Raymon H. Grogan, MD, director of the Endocrine Surgery Research Program at the University of Chicago, and colleagues evaluated 257 patients with DTC treated at the University of Chicago between 1951 and 1987. Median follow-up was 27 years. Researchers sought to compare DTC morphology and outcomes in patients with and without a prior history of therapeutic external radiation exposure.
Sixty-four percent of participants had a history of radiation exposure. Most participants had classic papillary thyroid carcinoma; 93.1% in the history of radiation exposure group and 91.8% in the no history of radiation exposure group.
There was a significant increase in overall survival in the history of radiation exposure group compared with the no history group after controlling for age at diagnosis (HR = 0.55; 95% CI, 0.34-0.89). No significant differences were found between the groups for risk of recurrence or DTC-specific mortality.
In the no history of radiation exposure group, women had a higher overall survival compared with men (HR = 1.95; 95% CI, 1.13-3.36). There was no difference in overall survival between men and women in the history of radiation exposure group.
“Our findings demonstrate that [history of radiation exposure] DTC-specific outcomes do not differ from those of [no history of radiation exposure]-DTC, while [overall survival] is improved,” the researchers wrote. “As rates of multifocality and extrathyroidal extension are also equivalent between the [history of radiation exposure and no history] groups, this may suggest that [history of radiation exposure] patients would also benefit from the expanded indications for thyroid lobectomy, as excision of the contralateral lobe may only be of prophylactic benefit.” – by Amber Cox
Disclosure: The researchers report no relevant financial disclosures.
Click Here to Manage Email Alerts