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Background: Female thyroid cancer survivors are more likely to have a higher risk of breast cancer compared to the general population, and the underlying causes are yet to be understood. The potential role of I-131 treatment on this association remains controversial., Methods: We pooled individual data of women who were treated for differentiated thyroid cancer from 1934 to 2005 in France, Italy and Sweden. Standardized incidence ratios (SIRs) for breast cancer were estimated by comparison with age, sex and calendar-year expected values of the general population in each country. We estimated breast cancer risk in relation to I-131 treatment using time-dependent Poisson models., Results: Of 8475 women (mean age at diagnosis: 45 years, range 2-90 years), 335 were diagnosed with breast cancer [SIR = 1.52, 95% confidence interval (CI): 1.36-1.69] during a median follow-up time of 12.7 years since diagnosis. Overall, breast cancer risk did not differ between women treated or not with I-131 (relative risk=1.07, 95% CI 0.84-1.35). However, breast cancer risk increased with increasing cumulative I-131 activity, without significant departure from linearity (excess relative risk per 100 mCi=17%, 95% CI: 2% to 38%). The higher risk associated with a cumulative I-131 activity of ≥100 mCi and ≥400 mCi was translated into 4 (95% CI -4 to 13) and 42 (95% CI -8 to 93) excess breast cancer cases per 10,000 person-years, respectively., Conclusions: An elevated risk was observed for the highest cumulative administered activity (>=400 mCi), and a significant dose-dependent association was observed among thyroid cancer survivors who were treated with I-131. However, overall, I-131 treatment might only explain partly the increase in breast cancer risk among female thyroid cancer survivors., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: This article presents the mortality data compiled among a cohort of workers at risk of internal uranium exposure and discusses the extent to which this exposure might differentiate them from other nuclear workers., Methods: The cohort consisted of 2897 Areva-NC-Pierrelatte plant workers, followed from 1st January 1968 through 31st December 2006 (79,892 person-years). Mortality was compared with that of the French population, by calculating Standardized Mortality Ratios (SMR) and 95% confidence intervals (CI95%). External radiation exposure was reconstructed using external dosimetry archives. Internal uranium exposure was assessed using a plant-specific job-exposure-matrix, considering six types of uranium compounds according to their nature (natural and reprocessed uranium [RPU] and solubility [fast-F, moderate-M, and slow-S]). Exposure-effect analyses were performed for causes of death known to be related to external radiation exposure (all cancers and circulatory system diseases) and cancer of uranium target-organs (lung and hematopoietic and lymphatic tissues, HLT)., Results: A significant deficit of mortality from all causes (SMR=0.58; CI95% [0.53-0.63]), all cancers (SMR=0.72; CI95% [0.63-0.82]) and smoking related cancers was observed. Non-significant 30%-higher increase of mortality was observed for cancer of pleura (SMR=2.32; CI95 % [0.75-5.41]), rectum and HLT, notably non-Hodgkin's lymphoma (SMR=1.38; CI95 % [0.63-2.61]) and chronic lymphoid leukemia (SMR=2.36; CI95% [0.64-6.03]). No exposure-effect relationship was found with external radiation cumulative dose. A significant exposure-effect relationship was observed for slowly soluble uranium, particularly RPU, which was associated with an increase in mortality risk reaching 8 to 16% per unit of cumulative exposure score and 10 to 15% per year of exposure duration., Conclusion: The Areva-NC-Pierrelatte workers cohort presents a non-significant over-mortality from HLT cancers, notably of lymphoid origin, unrelated to external radiation exposure. The pilot study suggests an association between mortality from the HLT and lung cancers and exposure to slowly soluble RPU compounds. The results of this study should be investigated further in more powerful studies, with a dose-response analysis based on individual assessment of uranium absorbed dose to uranium-target organs., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

The aim of this study is to search for relationships between histology, radioiodine ((131)I) uptake, fluorodeoxyglucose (FDG) uptake, and disease outcome in patients with metastatic thyroid cancer. Eighty patients with metastatic thyroid cancer (34 males, 46 females, mean age at the time of the diagnosis of metastases: 55 years) were retrospectively studied. All patients were treated with radioactive iodine and evaluated by FDG-positron emission tomography (PET). Primary tumor tissue sample was available in all cases. Forty-five patients (56%) had a papillary, 12 (15%) a follicular, and 23 (29%) a poorly differentiated thyroid cancer. Cellular atypias, necrosis, mitoses, thyroid capsule infiltration, and vascular invasion were frequently detected (70, 44, 52, 60, and 71% respectively). Metastases disclosed FDG uptake in 58 patients (72%) and (131)I uptake in 37 patients (45%). FDG uptake was the only significant prognostic factor for survival (P=0.02). The maximum standardized uptake value and the number of FDG avid lesions were also related to prognosis (P=0.03 and 0.009). Age at the time of the diagnosis of metastases (P=0.001) and the presence of necrosis (P=0.002) were independent predictive factors of FDG uptake. Radioiodine uptake was prognostic for stable disease (P=0.001) and necrosis for progressive disease at 1 year (P=0.001). Histological subtype was not correlated with in vivo tumor metabolism and prognosis. In conclusion, FDG uptake in metastatic thyroid cancer is highly prognostic for survival. Histological subtype alone does not correlate with (131)I/FDG uptake pattern and patient outcome. Well-differentiated thyroid cancer presenting histological features such as necrosis and FDG uptake on PET scan should be considered aggressive differentiated cancers.

Unlabelled: (131)I treatment in thyroid cancer patients may induce side effects, including extrathyroidal cancer and leukemia. There are still some uncertainties concerning parameters that may influence the effective half-life of (131)I and the absorbed doses by extrathyroidal organs., Methods: Whole-body retention of radioiodine was measured in 254 patients, and repeated quantitative whole-body scans and measurements of the urinary excretion of (131)I were performed on 30 of these patients., Results: The mean effective half-life (10.5 h) was shorter by 31%, with little difference between patients, in the 36 patients who received recombinant human thyroid-stimulating hormone than in the 218 patients who underwent thyroid hormone withdrawal (15.7 h). The residence times in the stomach and in the rest of the body were significantly shorter in patients who received recombinant human thyroid-stimulating hormone than in patients who underwent withdrawal, but the residence times were similar in the colon and bladder., Conclusion: In patients who undergo thyroid hormone withdrawal, the longer mean effective half-life is mainly due to delayed renal excretion of (131)I and results in dose estimates higher than the data in report 53 of the International Commission on Radiological Protection, which were obtained from healthy, euthyroid subjects.