Intermediate and long-term side effects of high-dose radioiodine therapy for thyroid carcinoma

The present investigation is an evaluation of intermediate and long-term side effects in patients after high-dose radioiodine treatment due to differentiated thyroid carcinoma.

A total of 203 patients were interviewed using a standardized questionnaire.

After radioiodine treatment, 76.8% of the patients reported intermediate (from discharge up to 3 mo) or long-term (more than 3 mo after treatment) complaints, and 61.1% reported long-term side effects. Nonstochastic side effects included sialoadenitis, which occurred in 33.0% of cases, and 27.1% of patients suffered from a transient loss of taste or smell. More than 1 yr after the last radioiodine application, 42.9% of patients suffered from reduced salivary gland function. Complete xerostomia occurred in 4.4% of patients. Hematological abnormalities were found in 9 patients. In 28.1% of patients a transient episode of alopecia was reported. In 22.7% of patients chronic or recurrent conjunctivitis was reported, and 4 patients underwent dacryocystorhinostomy; 13.8% of patients suffered from an increased frequency of influenza, but 3.4% reported a reduced occurrence of such infections. For sialoadenitis, the loss of taste/smell and dry mouth, the dependence on accumulated activity was significant.

Severe long-term side effects are rare after high-dose radioiodine treatment. Moderate side effects are common. The side effects are commonly the result of radiation damage to the salivary glands. The frequency of such complaints advocates regular protection of the salivary glands.