Value of postirradiation screening for thyroid nodules. A controlled study of recalled patients

Abstract

The occurrence of palpable thyroid abnormalities was determined in 214 persons with verified history of head and neck irradiation and in 243 concurrently examined, nonirradiated persons (control subjects). Examinations were performed by 2 physicians, each unaware of the medical history of the examinees and of the findings of the other examiner. Thyroid nodules, single of multiple, occurred in 6.1% of irradiated persons and in 4.5% of control subjects (95% confidence interval of the difference, -2.6% to +5.7%). Thyroid enlargement without nodules occurred in 5.6% of irradiated persons and in 3.7% of control subjects (95% confidence interval of the difference, -2.0% to +5.8%). Thyroid cancer was detected in 1 irradiated and 2 nonirradiated persons. This study did not find an excess number of thyroid abnormalities in subjects previously exposed to radiotherapy.