Increased Cancer Risk After Radioiodine
Aug
19
Written by:
8/19/2012
A total of 27,593 patients treated with radioiodine ablation for hyperthyroidism were compared to control subjects. The results showed:
Cancer incidence among hyperthyroid patients treated with RAI was higher than in the population-based control group (118.9 vs 94.9 per 10,000 person-years, rate ratio [RR], 1.25; 95% confidence interval [CI]: 1.08-1.46). Furthermore, incidence of stomach (RR, 1.75, 95% CI: 1.00-3.14), kidney (RR, 2.32; 95% CI: 1.06-5.09), and breast (RR, 1.53; 95% CI: 1.07-2.19) cancer was increased among RAI-treated patients. The relative risk of cancer increased with higher RAI dose administered. The increase in cancer incidence was statistically significant in patients treated at the age of 50-59 (RR, 1.44; 95% CI: 1.05-1.97) or older than 70 years (RR, 1.39; 95% CI: 1.05-1.82).
There was a 5-year latent period after the RAI treatment before the cancer incidence began to differ between the RAI-treated hyperthyroid patients and the control group. CONCLUSIONS: Cancer incidence, especially cancer of the stomach, kidney, and breast, was higher in patients treated with RAI for hyperthyroidism.
Other studies have shown an increase in small bowel and also colorectal cancers, which emphasizes the need for routine colorectal screening in patients who have had RAI ablation.
Source:
Pub Med. 2007. Saara Metso, Anssi Auvinen, Heini Huhtala, Jorma Salmi, Heikki Oksala, Pia Jaatinen, "Increased cancer incidence after radioiodine treatment for hyperthyroidism." Research Gate