[Hypothyroidism after radiotherapy of the neck area: monitoring of thyroid function is important].

We present three patients with primary hypothyroidism after previous radiotherapy of the neck area. Myxoedema coma occurred in one of these patients. Lifelong follow-up of thyroid function is recommended after radiotherapy of the neck. Monitoring of thyroid function should be performed at least once a year by the radiation oncologist or by the general practitioner.