Thyroid cancer patients treated with 131I: radiation dose to relatives after discharge from the hospital

Effectiveness of mobile robots collecting vital signs and radiation dose rate for patients receiving Iodine-131 radiotherapy: A randomized clinical trial

Objective

Patients receiving radionuclide 131I treatment expose radiation to others, and there was no clinical trial to verify the effectiveness and safety of mobile robots in radionuclide 131I isolation wards. The objective of this randomized clinical trial was to evaluate the effectiveness and safety of mobile robots in providing vital signs (body temperature and blood pressure) and radiation dose rate monitoring for patients receiving radionuclide therapy.

Methods

An open-label, multicenter, paired, randomized clinical trial was performed at three medical centers in Shanghai and Wuhan, China, from 1 April 2018 to 1 September 2018. A total of 72 participants were assigned to the group in which vital signs and radiation doses were both measured by mobile robots and conventional instruments. Intergroup consistency, completion rate, and first success rate were the primary effectiveness measures, and vital sign measurement results, the error rate of use, and subjective satisfaction were secondary indicators. Adverse events related to the robot were used to assess safety.

Results

Of the 72 randomized participants (median age, 39.5; 27 [37.5%] male participants), 72 (100.0%) completed the trial. The analysis sets of full analysis set, per-protocol set, and safety analysis set included 72 cases (32 cases in Center A, 16 cases in Center B, and 24 cases in Center C). The consistency, completion rate, and first success rate were 100% (P = 1.00), and the first success rates of vital signs and radiation dose rate were 91.7% (P = 1.000), 100.0% (P = 0.120), and 100.0% (P = 1.000). There was no significant difference in vital signs and radiation dose rate measurement results between the robot measurement group and the control group (P = 0.000, 0.044, and 0.023), and subjective satisfaction in the robot measurement group was 71/72 (98.6%), compared to 67/72 (93.1%) in the control group. For safety evaluation, there was no adverse event related to the mobile robot.

Conclusion

The mobile robots have good effectiveness and safety in providing vital signs and radiation dose rate measurement services for patients treated with radionuclides.

THE COMPARISON OF THE EXTERNAL DOSE RATE MEASUREMENT OF CHILDREN AND ADOLESCENT PATIENTS WITH ADULT PATIENTS TREATED WITH RADIOIODINE THERAPY

The aim of this study is to evaluate the radiation safety of caregiving people contacting the child and adolescent patients with thyroid cancer who received radioactive iodine-131 (RIT) treatment by comparison with external dose rate measurements of adult patients according to their administered activities and days of hospitalization. We retrospectively evaluated external dose rate measurement of 158 children and adolescent patients and 158 adult patients. During the RIT, the hospitalization time were grouped as 2, 3 and 4 d, and the administered activities as <3700, 3700 and >3700 MBq. The values of external dose rate measurements of children and adolescents were statistically significantly higher than the adult group. Different approaches in radiation safety rules are required for children and adolescents. In terms of radiation safety, we suggest that more specific regulations for family members and caregivers should be established and informed.

Higher body weight and distant metastasis are associated with higher radiation exposure to the household environment from patients with thyroid cancer after radioactive iodine therapy

There were insufficient data regarding radiation exposure to the household environment from patients with thyroid cancer who received radioactive iodine (RAI) therapy in Asia; we therefore performed the present study at the Chang Gung Memorial Hospital in Keelung, Taiwan.Patients with papillary or follicular thyroid cancer who received 3.7 GBq (100 mCi) RAI were enrolled in this prospective hospital-based study. The enrolled patients were asked to place a thermoluminescent dosimeter in the living room, bedroom, and bathroom of their houses for 4 weeks to measure radiation exposure to the household environment.A total of 43 patients (18 men and 25 women; mean age 51 ± 13 years) who received 3.7 GBq (100 mCi) RAI completed the study. The mean value of total radiation exposure over 4 weeks from the patients to the bedroom, bathroom, and living room (eliminating the background radiation factor) was 0.446 ± 0.304 (0.088-1.382) mSv. We divided the patients into 2 groups: those with more than and less than the mean value of total radiation exposure to the bedroom, bathroom, and living room. Factors associated with the higher amount of radiation exposure from the patients to the household environment were patient body weight (P = .025, univariate analysis; P = .037, multivariate analysis, odds ratio [95% confidence interval] 1.067 [1.004-1.134]) and distant metastases based on I post-therapy scanning (P = .041, univariate analysis; P = .058, multivariate analysis, odds ratio [95% confidence interval] 6.453 [0.938-44.369]); age, sex, body mass index, renal function, serum stimulated thyroglobulin level, and recombinant human thyroid-stimulating hormone use were not associated with the amount of radiation exposure from the patients to the household environment.Higher body weight and distant metastases may be the best predictors for higher radiation exposure to the household environment from patients with thyroid cancer after RAI therapy.

Radiation exposure to caregivers from patients undergoing common radionuclide therapies: a review

The contribution of radionuclide therapies (RNTs) to effective patient treatment is widely appreciated. The administration of high doses has necessitated investigating the potential radiation hazard to caregivers from patients undergoing RNTs. This work aimed to review the literature regarding measured effective doses to caregivers from such patients. The main selection criterion was the presence of real radiation exposure measurements. The results were categorised according to the treatment protocol and dose parameters. Analysis of the collected data demonstrated that the measured effective dose values were within the dose constraints defined by the International Commission on Radiological Protection, provided that the radiation protection instructions were followed by both patients and caregivers. In conclusion, the radiation risk for caregivers was almost negligible. In this context, treatments could be administered more often on an outpatient basis, once cost-effectiveness criteria were established and radiation protection training and procedures were appropriately applied.

Estimated dose from diagnostic nuclear medicine patients to people outside the Nuclear Medicine department

Patients undergoing nuclear medicine scans can be a source of radiation exposure for staff, family and the public. In this paper, 12 common nuclear medicine scans are considered. Doses are estimated for a range of scenarios, to hospital staff, to the public and to the patients' co-workers and family. Estimates are based on dose rates measured as patients left the Nuclear Medicine department. Radiopharmaceutical clearance is calculated from biokinetic models described in International Commission on Radiological Protection publications 53, 80 and 106. For all scan types, and all scenarios, doses are estimated to be substantially less than the trigger level of 300 µSv. Within the hospital, Intensive Care Unit staff receive the highest dose (up to 80 µSv) from patients who have had a myocardial scan or a positron emission tomography scan. For out-patients, the highest doses (up to 100 µSv) are associated with travel on public transport (for 4 h) on the same day as the scan.