Mucoepidermoid carcinomas of the salivary glands after high-dose radioiodine therapy.

Background: High-dose radioiodine therapy following total thyroidectomy is standard for patients suffering from differentiated thyroid carcinoma and c ontributes significantly to their favourable prognosis. Due to active iodin e accumulation, high focal radiation doses are received by the salivary gla nds. Patients/Result: Report on two patients, who received multiple high-do se radioiodine treatments because of a differentiated metastatic thyroid ca rcinoma. A few years later, they developed a mucoepidermoid carcinoma of th e salivary glands. Due to the high cumulative radiation dose, radiation-ind uced secondary malignancies following radiation-induced sialadenitis appear s likely, although no causal connection could be proven. Conclusion: Consis tent protection of the salivary glands during radioiodine therapy as well a s the follow-up of the many long-term survivors of differentiated thyroid c arcinomas is desirable to further lower the salivary gland-related side eff ects and to detect secondary malignancies as early as possible.