Incidence of primary hypothyroidism in patients exposed to therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland.

INTRODUCTION: Hypothyroidism is a known consequence of external-beam radiotherapy to the neck encompassing a part or whole of the thyroid gland. In this non-randomized prospective study, we have tried to evaluate the response of the thyroid gland to radiation by assessing thyroid function before irradiation and at regular intervals after irradiation. AIMS AND OBJECTIVES: THE AIM OF THIS STUDY WERE TO ASSESS IN THE CANCER PATIENTS, WHO WERE EXPOSED TO THE THERAPEUTIC EXTERNAL BEAM RADIATION, WHERE RADIATION PORTALS INCLUDE A PART OR WHOLE OF THE THYROID GLAND: the incidence of primary hypothyroidism, the time required to become hypothyroid, any relation between the total dose for the development of hypothyroidism, and whether there are any patient or treatment-related factors that are predictive for the development of hypothyroidism, including the use of concurrent chemotherapy. MATERIALS AND METHODS: This non-randomized, prospective study was conducted for a period of 2 years in which thyroid function was assessed in 59 patients (cases) of head and neck cancer, breast cancer, lymphoma patients and other malignancies, who had received radiotherapy to the neck region. 59 euthyroid healthy patients (controls) were also taken, who had not received the neck irradiation. These patients/controls were assessed periodically for 2 years. RESULTS: The incidence of hypothyroidism after external beam radiation therapy (EBRT) to neck where radiation portals include part or whole of the thyroid gland was 16.94%, seven cases had subclinical hypothyroidism (11.86%) and three cases had clinical hypothyroidism (5.08%). Mean time for development of hypothyroidism was 4.5 months. There was no effect of age, gender, primary tumor site, radiation dose and chemotherapy, whether neoadjuvant or concurrent with the development of hypothyroidism. CONCLUSION: In summary, we found that thyroid dysfunction is a prevalent, yet easily treatable source of morbidity in patients undergoing radiation therapy to neck where radiation portals include a part or whole of the thyroid gland.

Role of cervical ultrasonography in primary hyperparathyroidism.

AIM: To evaluate the role of USG in the preoperative localization of parathyroid adenomas in patients with symptomatic hyperparathyroidism and to compare its usefulness with that of scintigraphy scan and postoperative findings. MATERIAL AND METHODS: Twenty-five patients with symptomatic primary hyperparathyroidism were subjected to USG of the neck and nuclear scintigraphy, followed by surgery. The results were independently analyzed and compared with per-operative findings. RESULTS: The 25 patients had a total of 28 abnormal glands: 22 solitary adenomas, and 6 multiple adenomas (two each in three patients). USG detected 20 out of 22 solitary adenomas and three out of six multiple adenomas. USG missed five abnormal glands, two of which were in the neck and three in the mediastinum. Scintigraphy was positive in 26 abnormal glands, out of which 22 were single and four were multiple. Two abnormal glands were missed: one in the neck and one in the mediastinum. CONCLUSION: As limited neck dissection for primary hyperparathyroidism becomes increasingly popular, USG has been found to be a sensitive, specific, and easily available noninvasive investigation for parathyroid localization. It can be easily offered to patients as a method for preoperative localization prior to limited parathyroid surgery outside tertiary care settings.