Radiation‐associated thyroid carcinoma

Abstract

Since February, 1977, 735 patients having a history of receiving radiation therapy for benign conditions of the head and neck areas during infancy and childhood were examined in a thyroid screening program, and 159 patients were found to have palpable thyroid nodules. These patients had thyroid function tests and indirect laryngoscopy and were followed closely on suppression therapy consisting of either Cytomel or thyroid extract. Thyroidectomy was advised in those in whom the nodules persisted or increased in size. This study documents the incidence of carcinoma and other benign pathological changes and postoperative complications in this group of patients. So far, 49 patients had either a lobectomy with isthmusectomy or a total thyroidectomy. Eleven patients were found to have carcinoma (six had papillary, four had mixed papillary and follicular, and one had follicular carcinoma). Three patients had a therapeutic modified neck dissection following the documentation of microscopic involvement of paratracheal lymph nodes. A high incidence of chronic nonspecific thyroiditis, postradiation fibrosis, and follicular adenomas were also found in these patients. Three patients had temporary hypocalcemia (two weeks) and none had wound infection, hematoma, or postoperative nerve palsy. Of patients who had surgical resection, 22.4% showed thyroid carcinoma.

The effect of total body irradiation and bone marrow transplantation during childhood and adolescence on growth and endocrine function

“…Clinical hypothyroidism was not common amongst our patients, with only one permanently receiving replacement therapy. Nonetheless, untreated compensated hypothyroidism may contribute to the development of thyroid neoplasms in later life (Constine et al, 1984: Razack et al, 1980 but so far there is no evidence to suggest that fractionation avoids this problem (Sanders et al, 1986).…”

Post‐radiotherapy cribriform‐morular thyroid carcinoma

“…4 In a study conducted by Razack et al, the pathologies of patients who received radiotherapy during childhood and developed malignancy were reported as papillary, mixed papillary, and follicular and follicular carcinoma. 5 Hypothyroidism after head and neck radiotherapy, as it developed in our patient, is a well-known and common side effect. 6 In this respect, our case is a first.…”

“…Literature data show that histopathologic examination findings are nonspecific for radiotherapy-associated thyroid malignancies. 3,5 Thus, the development of cribriformmorular thyroid carcinoma in our patient may be sporadic or due to radiotherapy.…”

“…It is known that two‐thirds of thyroid malignancies that develop after external radiotherapy are benign and that one‐third are malignant and mostly well‐differentiated cancers 4 . In a study conducted by Razack et al, the pathologies of patients who received radiotherapy during childhood and developed malignancy were reported as papillary, mixed papillary, and follicular and follicular carcinoma 5 . Hypothyroidism after head and neck radiotherapy, as it developed in our patient, is a well‐known and common side effect 6 .…”

Radiation and thyroid carcinoma: Radiotherapy, head and neck regions, thyroid carcinoma

“…Others claim accuracy rates as high as However, although no study of fine-needle aspiration performed solely in patients with radiation thyroiditis is currently available, this technique would seem to be inadequate since about half of those patients with nodular gland on palpation have microscopic cancer discovered by serial sections and it is not unusual for the malignant focus to be quite distant from the palpated abnormality; indeed in 19.5% of the patients with a palpable nodule, carcinoma has been found in the contralateral lobe. 16 High resolution ultrasonography has been reported to allow detection of lesions as small as 3 mm?6 However, its accuracy in the evaluation of radiation thyroiditis has not been documented. Currently, fine-needle aspiration should be considered helpful only by its positivity when dealing with radiation-induced thyroid car~inoma.~' At any rate, the proper screening of this population requires adherence to a strict protocol.…”