Objective: This study aimed to evaluate the association between occupational radiation exposure and changes in thyroid hormone levels among medical radiation workers. Methods: This retrospective cohort study included 2,946 radiation workers from 20 Guangzhou hospitals. Data on general characteristics, participant radiation dosimetry, and thyroid function test results [thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroid hormone (T4)] were extracted from dosimetry and medical records. The generalized estimating equation was used to evaluate the trend of changes in thyroid hormone levels over time and was adjusted for age, gender, and occupation. Results: The average annual effective dose was very low and showed a general downward trend. During the follow-up period, changes in T3 and T4 levels among radiation workers were -0.015 [95% confidence interval ( Conclusion Thyroid hormone secretion might be affected even in low-dose radiation exposure environments.
Adult ; China ; Cohort Studies ; Female ; Humans ; Male ; Middle Aged ; Occupational Exposure/adverse effects* ; Radiation Exposure/adverse effects* ; Retrospective Studies ; Thyroid Hormones/radiation effects* ; Young Adult

Adult ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Radiation, Ionizing ; Radiology Department, Hospital ; Serum ; metabolism ; radiation effects ; Testosterone ; blood ; Thyroid Hormones ; blood

OBJECTIVETo evaluate the effect of 90Y-DOTATOC and 131I-MIBG in treatment of metastatic medullary thyroid carcinoma (MTC).

METHODSTwelve histologically confirmed patients with metastatic MTC were included. All patients underwent both 111In-DTPA-octreotide imaging and 131I/ 123I-meta-iodobenzylguanidine (MIBG) imaging. According to the results of the combined imaging, positive patients were selected to be treated with 90Y-DOTA-D-Phe1-Tyr3-octreotide (90Y-DOTATOC) or 131I-MIBG, respectively. The therapeutic procedures of targeted internal radiation were performed with 3.33 GBq 90Y-DOTATOC at 6-week intervals, or 11.1 GBq 131I-MIBG with a minimum interval of three months.

RESULTSThe imaging procedure was positive in all 12 patients: 111In-DTPA-octreotide imaging in eight patients, 131I/ 123I-MIBG imaging in six patients. According to the results of combined imaging, we identified four patients to be treated with 90Y-DOTATOC, and five patients with 131 I-MIBG. After three to five sessions of treatment, three patients with partial remission and six with stable disease were observed. The effective rate was 3/9 (33.3%) and the overall tumor response rate was 9/9 (100%). No relevant toxicity was observed.

CONCLUSIONThe combined imaging technique can be used to identify patients for effective radionuclide treatment. The treatment with 90Y-DOTATOC or 131I-MIBG is well tolerated and may improve the fate of patients with metastatic MTC.

3-Iodobenzylguanidine ; therapeutic use ; Adult ; Aged ; Antineoplastic Agents ; therapeutic use ; Carcinoma, Medullary ; metabolism ; radiotherapy ; secondary ; Female ; Follow-Up Studies ; Humans ; Indium Radioisotopes ; Male ; Middle Aged ; Octreotide ; analogs & derivatives ; therapeutic use ; Pentetic Acid ; analogs & derivatives ; Positron-Emission Tomography ; Remission Induction ; Thyroid Gland ; diagnostic imaging ; pathology ; radiation effects ; Thyroid Hormones ; metabolism ; Thyroid Neoplasms ; metabolism ; pathology ; radiotherapy ; Treatment Outcome ; Yttrium Radioisotopes ; therapeutic use