Health-related quality of life and radioiodine therapy in thyroid cancer patients: a before-and-after study.

OBJECTIVE: Thyroid cancers are on the rise, but the associated vital prognosis and long-term survival rates are very good. Therefore, treated patients' quality of life and psychological well-being are important considerations. The treatment usually involves surgery and radioactive iodine (radioiodine) ablation. This study aims to investigate potential effects of radioiodine ablation therapy on health-related quality of life, anxiety and depression symptoms, and nutritional status at 6 months post-therapy. METHODS: This study included 136 patients diagnosed with thyroid cancer. Absorbed doses to the salivary glands were estimated from dosimeters worn by patients. Patient health-related quality of life, psychological status and nutritional status were assessed before and 6 months after therapy using standardized questionnaires (including SF-36, Hospital Anxiety and Depression (HAD) scale). Statistical analyses included random-effects logistic and linear regressions adjusted for potential confounders. RESULTS: While no significant association was found between radioiodine exposure and anxiety or depression symptoms, or nutritional status, a significant increase in the SF-36 role physical sub- score was observed in relation with the salivary gland dose (ß= 6.54, 95%CI 2.71;10.36 for a 1-Gy increase). CONCLUSIONS: The findings suggest an improved physical health-related quality of life, namely reduced pain and functional impairment, 6 months after radioiodine therapy in thyroid cancer patients. No significant association was found between radioiodine exposure and mental health-related quality of life, anxiety or depression scores nor nutritional status. This study does not provide any evidence that radioiodine therapy has a potentially adverse effect on patient health-related quality of life.

Central nervous system tumours and occupational ionising radiation exposure: a nested case-control study among the ORICAMs cohort of healthcare workers in France.

OBJECTIVE: This study aimed at investigating the relationship between occupational exposure to external ionising radiation and central nervous system (CNS) tumours mortality in healthcare workers working in France. DESIGN AND SETTING: The Occupational Radiation-Induced Cancer in Medical staff (ORICAMs) nested case-control study was conducted based on the dosimetric records of the national register of occupational dosimetry (Système d'information de la surveillance de l'exposition aux rayonnements ionisants). PARTICIPANTS AND METHODS: 33 CNS tumour deaths occurred between 2002 and 2012 among the ORICAMs cohort composed of 164 015 healthcare workers. Each case was matched to five controls alive at the time of the corresponding case's death, based on sex, year of birth, date of enrolment in the cohort and duration of follow-up. All participants were badge monitored for external radiation exposure, expressed in Hp(10). Conditional logistic regression was used to analyse the dose-response relationship between radiation dose and CNS mortality. RESULTS: Cases were exposed to a mean cumulative career radiation dose of 5.8±13.7 (max: 54.3) millisievert (mSv) compared with 4.1±15.2 (142.2) mSv for controls. No statistically significant association was found between CNS tumour mortality and cumulative whole-body career dose (OR=1.00, 95% CI 0.98 to 1.03), duration of exposure (OR=1.03; 95% CI 0.95 to 1.12) or age at first exposure (OR=0.98; 95% CI 0.91 to 1.06). CONCLUSION: We found no evidence of an association between external radiation exposure and CNS tumour risk in healthcare workers. Limitations of the study include low statistical power and short duration of follow-up.

Radiation protection in a cohort of healthcare workers: knowledge, attitude, practices, feelings and IR-exposure in French hospitals.

The number of healthcare workers occupationally exposed to ionizing radiation (IR) is increasing every year. As health effects from exposure to low doses IR have been reported, radiation protection (RP) in the context of occupational activities is a major concern. This study aims to assess the compliance of healthcare workers with RP policies, according to their registered cumulative dose, profession, and perception of radiation self-exposure and associated risk. Every healthcare worker from one of the participating hospitals in France with at least one dosimetric record for each year 2009, 2014, and 2019 in the SISERI registry was included and invited to complete an online questionnaire including information on the worker's occupational exposure, perception of IR-exposure risk and RP general knowledge. Hp(10) doses were provided by the SISERI system. Multivariate logistic regressions were used. Dosimeter wearing and RP practices compliance were strongly associated with 'feeling of being IR-exposed' (OR = 3.69, CI95% 2.04-6.66; OR = 4.60, CI95% 2.28-9.30, respectively). However, none of these factors was associated with RP training courses attendance. The main reason given for non-compliance is unsuitability or insufficient numbers of RP devices. This study provided useful information for RP policies. Making exposed workers aware of their own IR-exposure seems to be a key element to address in RP training courses. This type of questionnaire should be introduced into larger epidemiological studies. Dosimeter wearing and RP practices compliance are associated to feeling being IR-exposed. RP training courses should reinforce workers' awareness of their exposure to IR.

Cohort profile: ORICAMs, a French cohort of medical workers exposed to low-dose ionizing radiation.

Medical personnel represent the largest group of workers occupationally exposed to ionizing radiation. Although the health risks associated with occupational exposure to low doses of ionizing radiation in the medical field have been investigated in several national cohorts, no study has been conducted in France to date. The ORICAMs (Occupational Radiation Induced Cancer in Medical staff) cohort is a nationwide French longitudinal cohort of medical workers exposed to ionizing radiation aiming to investigate the risk of radiation-associated cancer and non-cancer mortality. The ORICAMs cohort was set up in 2011 and includes all medical personnel monitored for ionizing radiation exposure with at least one dosimetric record in the SISERI database (the national registry for monitoring ionizing radiation exposure in workers) over the period 2002-2012. Causes of death were abstracted from death certificates and coded according to ICD-10. The follow-up ended on 31/12/2013. Standardized mortality ratios (SMRs) were calculated by cause of death to compare the mortality in the cohort to that in the French population, by gender, age group and calendar period. Among the 164,015 workers included in the cohort (60% women) a total of 1,358 deaths (892 in male and 466 in female) were reported. The observed number of all-cause deaths was significantly lower than expected based on national rates in both male (SMR = 0.35; 95% CI: 0.33, 0.38; ndeaths = 892) and female (SMR = 0.41; 95% CI: 0.38, 0.45; ndeaths = 466). This analysis leads to the conclusion that mortality in French workers exposed to medical radiation is significantly lower than the national reference rates. However, these results based on a comparative analysis with national rates may be impacted by the healthy worker effect towards low SMRs, and do not enable to establish a potential relationship between occupational exposure and mortality risk, even if we may suspect an impact of high SES of these professionals on the observed decreased mortality. Thus, further dose-response analyses based on individual ionizing radiation exposure and job's type will be conducted to characterize correlation between risk of cancer mortality and occupational exposure.

Dysfunction of the Salivary and Lacrimal Glands After Radioiodine Therapy for Thyroid Cancer: Results of the START Study After 6-Months of Follow-Up.

Background: Understanding of changes in salivary and lacrimal gland functions after radioactive iodine therapy (131I-therapy) remains limited, and, to date, no studies have evaluated dose-response relationships between absorbed dose from 131I-therapy and dysfunctions of these glands. This study investigates salivary/lacrimal dysfunctions in differentiated thyroid cancer (DTC) patients six months after 131I-therapy, identifies 131I-therapy-related risk factors for salivary/lacrimal dysfunctions, and assesses the relationships between 131I-therapy radiation dose and these dysfunctions. Methods: A cohort study was conducted involving 136 DTC patients treated by 131I-therapy of whom 44 and 92 patients received 1.1 and 3.7 GBq, respectively. Absorbed dose to the salivary glands was estimated using a dosimetric reconstruction method based on thermoluminescent dosimeter measurements. Salivary and lacrimal functions were assessed at baseline (T0, i.e., immediately before 131I-therapy) and six months later (T6) using validated questionnaires and salivary samplings, with and without stimulation of the salivary glands. Statistical analyses included descriptive analyses and random-effects multivariate logistic and linear regressions. Results: There was no difference between T0 and T6 in the level of parotid gland pain, nor was there difference in the number of patients with hyposalivation, but there were significantly more patients with dry mouth sensation and dry eyes after therapy compared with baseline. Age, menopause, depression and anxiety symptoms, history of systemic disease, and not taking painkillers in the past three months were found to be significantly associated with salivary or lacrimal disorders. Significant associations were found between 131I-exposure and salivary disorders adjusted on the previous variables: for example, per 1-Gy increase in mean dose to the salivary glands, odds ratio = 1.43 [CI 1.02 to 2.04] for dry mouth sensation, ß = -0.08 [CI -0.12 to -0.02] mL/min for stimulated saliva flow, and ß = 1.07 [CI 0.42 to 1.71] mmol/L for salivary potassium concentration. Conclusions: This study brings new knowledge on the relationship between the absorbed dose to the salivary glands from 131I-therapy and salivary/lacrimal dysfunctions in DTC patients six months after 131I-therapy. Despite the findings of some dysfunctions, the results do not show any obvious clinical disorders after the 131I-therapy. Nevertheless, this study raises awareness of the risk factors for salivary disorders, and calls for longer follow-up. Clinical Trials Registration: Number NCT04876287 on the public website (ClinicalTrials.gov).

Occupational exposure to ionizing radiation in medical staff: trends during the 2009-2019 period in a multicentric study.

OBJECTIVES: Health workers exposed to ionizing radiation account for + 50% of workers exposed to man-made radiation in France. Over the last decade, the use of radiation in medicine has increased due to the introduction of new practices. The EXposition des Professionnels de santE aux RayonnemenTs ioniSants study aims to evaluate and characterize the trends in radiation exposure of health workers in France between 2009 and 2019. METHODS: This retrospective study includes all health workers with at least one dosimetric record in the system for occupational dosimetry registration (Système d'information de la surveillance de l'exposition aux rayonnements ionisants) database for each of the years 2009, 2014, and 2019, in the hospitals included in the study. Individual external doses and socio-professional data were collected. Statistical analyses include descriptions, graphs, and logistic regressions. RESULTS: A total of 1457 workers were included (mean age: 39.8 years, 59% women). The average exposure significantly decreased between 2009 and 2019 (-0.008 mSv/year, p < 0.05). There were large discrepancies in trends according to professions, departments, hospitals, and gender. Over the 10-year study period, radiologic technologists and physicians were the most exposed (0.15 mSv (95%CI 0.14-0.16) and 0.13 mSv (0.06-0.21), respectively), but their exposure tended to decrease. Workers in nuclear medicine departments had the highest radiation exposure (0.36 mSv (0.33-0.39)), which remained stable over time. Thirty-eight percent of recorded doses were nonzero in 2009, decreasing to 20% in 2019. CONCLUSIONS: This study allowed to identify physicians and radiologic technologists in nuclear medicine departments as the most exposed medical workers in France, and to show an overall decrease trend in radiation exposure. This should be instructive for radiation monitoring and safety of exposed medical workers. KEY POINTS: • Radiation exposure of healthcare workers in most medical departments has steadily decreased between 2009 and 2019 in several French hospitals. • The number of zero doses consistently increased during the study period. • Workers in nuclear medicine departments are the most exposed, especially radiologic technologists and physicians.

Ionizing radiation exposure during adulthood and risk of developing central nervous system tumors: systematic review and meta-analysis.

Many studies on ionizing radiation (IR) exposure during childhood have shown deleterious effects on the central nervous system (CNS), however results regarding adult exposure are inconsistent, and no systematic reviews have been performed. The objectives are to synthesize the findings and draw evidence-based conclusions from epidemiological studies on the risk of benign and malignant brain and CNS tumors in humans exposed to low-to-moderate doses (< 0.5 Gy) of IR during adulthood/young adulthood. A systematic literature search of four electronic databases, supplemented by a hand search, was performed to retrieve relevant epidemiological studies published from 2000 to 2022. Pooled excess relative risk (ERRpooled) was estimated using a random effect model. Eighteen publications were included in the systematic review and twelve out of them were included in a meta-analysis. The following IR sources were considered: atomic bombs, occupational, and environmental exposures. No significant dose-risk association was found for brain/CNS tumors (ERRpooled at 100 mGy = - 0.01; 95% CI: - 0.05, 0.04). Our systematic review and meta-analysis did not show any association between exposure to low-to-moderate doses of IR and risk of CNS tumors. Further studies with histological information and precise dose assessment are needed.

Risk of Developing Non-Cancerous Central Nervous System Diseases Due to Ionizing Radiation Exposure during Adulthood: Systematic Review and Meta-Analyses.

Background: High-dose ionizing radiation (IR) (>0.5 Gy) is an established risk factor for cognitive impairments, but this cannot be concluded for low-to-moderate IR exposure (<0.5 Gy) in adulthood as study results are inconsistent. The objectives are to summarize relevant epidemiological studies of low-to-moderate IR exposure in adulthood and to assess the risk of non-cancerous CNS diseases. Methods: A systematic literature search of four electronic databases was performed to retrieve relevant epidemiological studies published from 2000 to 2022. Pooled standardized mortality ratios, relative risks, and excess relative risks (ERR) were estimated with a random effect model. Results: Forty-five publications were included in the systematic review, including thirty-three in the quantitative meta-analysis. The following sources of IR-exposure were considered: atomic bomb, occupational, environmental, and medical exposure. Increased dose-risk relationships were found for cerebrovascular diseases incidence and mortality (ERRpooled per 100 mGy = 0.04; 95% CI: 0.03−0.05; ERRpooled at 100 mGy = 0.01; 95% CI: −0.00−0.02, respectively) and for Parkinson's disease (ERRpooled at 100 mGy = 0.11; 95% CI: 0.06−0.16); Conclusions: Our findings suggest that adult low-to-moderate IR exposure may have effects on non-cancerous CNS diseases. Further research addressing inherent variation issues is encouraged.

Salivary Dysfunctions and Consequences After Radioiodine Treatment for Thyroid Cancer: Protocol for a Self-Controlled Study (START Study).

BACKGROUND: Following radioiodine (131I) therapy of differentiated thyroid cancer, the salivary glands may become inflamed, leading to dysfunctions and decreases in patients' nutritional status and quality of life. The incidence of these dysfunctions after 131I-therapy is poorly known, and no clinical or genetic factors have been identified to date to define at-risk patients, which would allow the delivered activity to be adapted to the expected risk of salivary dysfunctions. OBJECTIVE: The aims of this study are to estimate the incidence of salivary dysfunctions, and consequences on the quality of life and nutritional status for patients after 131I-therapy; to characterize at-risk patients of developing posttreatment dysfunctions using clinical, biomolecular, and biochemical factors; and to validate a dosimetric method to calculate the dose received at the salivary gland level for analyzing the dose-response relationship between absorbed doses to salivary glands and salivary dysfunctions. METHODS: This prospective study aims to include patients for whom 131I-therapy is indicated as part of the treatment for differentiated thyroid cancer in a Paris hospital (40 and 80 patients in the 1.1 GBq and 3.7 GBq groups, respectively). The follow-up is based on three scheduled visits: at inclusion (T0, immediately before 131I-therapy), and at 6 months (T6) and 18 months (T18) posttreatment. For each visit, questionnaires on salivary dysfunctions (validated French tool), quality of life (Hospital Anxiety and Depression scale, Medical Outcomes Study 36-Item Short Form Survey), and nutritional status (visual analog scale) are administered by a trained clinical research associate. At T0 and T6, saliva samples and individual measurements of the salivary flow, without and with salivary glands stimulation, are performed. External thermoluminescent dosimeters are positioned on the skin opposite the salivary glands and at the sternal fork immediately before 131I administration and removed after 5 days. From the doses recorded by the dosimeters, an estimation of the dose received at the salivary glands will be carried out using physical and computational phantoms. Genetic and epigenetic analyses will be performed to search for potential biomarkers of the predisposition to develop salivary dysfunctions after 131I-therapy. RESULTS: A total of 139 patients (99 women, 71.2%; mean age 47.4, SD 14.3 years) were enrolled in the study between September 2020 and April 2021 (45 and 94 patients in the 1.1 GBq and 3.7G Bq groups, respectively). T6 follow-up is complete and T18 follow-up is currently underway. Statistical analyses will assess the links between salivary dysfunctions and absorbed doses to the salivary glands, accounting for associated factors. Moreover, impacts on the patients' quality of life will be analyzed. CONCLUSIONS: To our knowledge, this study is the first to investigate the risk of salivary dysfunctions (using both objective and subjective indicators) in relation to organ (salivary glands) doses, based on individual dosimeter records and dose reconstructions. The results will allow the identification of patients at risk of salivary dysfunctions and will permit clinicians to propose a more adapted follow-up and/or countermeasures to adverse effects. TRIAL REGISTRATION: ClinicalTrials.gov NCT04876287; https://clinicaltrials.gov/ct2/show/NCT04876287. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/35565.

Biomarkers of Genotoxicity in Medical Workers Exposed to Low-Dose Ionizing Radiation: Systematic Review and Meta-Analyses.

Medical staff represent the largest group of workers occupationally exposed to ionizing radiation (IR). Chronic exposure to low-dose IR may result in DNA damage and genotoxicity associated with increased risk of cancer. This review aims to identify the genotoxicity biomarkers that are the most elevated in IR-exposed vs. unexposed health workers. A systematic review of the literature was performed to retrieve relevant studies with various biomarkers of genotoxicity. Subsequent meta-analyses produced a pooled effect size for several endpoints. The search procedure yielded 65 studies. Chromosome aberrations (CA) and micronuclei (MN) frequencies were significantly different between IR-exposed and unexposed workers (θpooled = 3.19, 95% CI 1.46-4.93; and θpooled = 1.41, 95% CI 0.97-1.86, for total aberrant cells and MN frequencies, respectively), which was not the case for ring chromosomes and nucleoplasmic bridges. Although less frequently used, stable translocations, sister chromatid exchanges (SCE) and comet assay endpoints were also statistically different between IR-exposed and unexposed workers. This review confirms the relevance of CA and MN as genotoxicity biomarkers that are consistently elevated in IR-exposed vs. unexposed workers. Other endpoints are strong candidates but require further studies to validate their usefulness. The integration of the identified biomarkers in future prospective epidemiological studies is encouraged.