One hundred fifty-one patients with a history of childhood irradiation to the head, neck, and thorax had neck explorations (142 for "cold" thyroid nodules and 9 for hypercalcemia). Fifty-nine of the patients had thyroid carcinoma, and associated glandular tumors were found in 20 others. In addition, 6 female patients developed breast carcinoma; 4 of these women also had thyroid carcinoma. In this series, 48.6% of the patients irradiated for acne and 36.4% with tonsil and adenoid irradiation developed thyroid carcinoma, but only 10.5% with thymic irradiation did so. It is suggested that the workup on these patients include not only complete thyroid and parathyroid testing, but also a careful examination of all salivary glands, both major and minor. Women should have thorough breast examinations and should perhaps be followed as if they were in the potentially high-risk breast group. When thyroid surgery is performed, a total thyroidectomy is recommended.