Cobalt-60 therapy of Hodgkin's disease and the subsequent development of hypothyroidism

Five patients with Hodgkin's disease developed hypothyroidism following cobalt-60 therapy to the cervical area. The hypothyroid state was detected from 5 to 12 months after completion of the cobalt-60 radiation therapy. The patient's primary complaints were lethargy and a “bloated” sensation. Physical findings were sparse except for edema of the extremities or the periorbital area. Laboratory studies are presented that confirmed the hypothyroidism. In this particular type of patient, fatigue and weight gain are vague and common complaints that warrant further evaluation to determine if post-radiation therapy hypothyroidism exists.