Radiation Exposure to Comforters and Carers During Paediatric Molecular Radiotherapy

Background: To show whether the incidental radiation exposure received by comforters and carers of children undergoing molecular radiotherapy was kept as low as reasonably achievable and was within English national dose constraints.

Procedure: The radiation exposure of adult comforters and carers was routinely monitored with a whole body personal dose meter while the child was in hospital. Data were collected on iodine-131 meta-iodobenzylguanidine ( I-mIBG), lutetium-177 DOTATATE ( Lu-DOTATATE), and iodine-131 sodium iodide ( I-NaI) treatments.

Results: Data were available for 50 treatments with high-administered activity double-infusion I-mIBG and 12 single administrations; 15 Lu-DOTATATE treatments and 28 I-NaI administrations. The median age was 7 years (1-18). The median administered activity of: I-mIBG was 16.2 GBq (6.8-59 GBq) for double infusion patients and 8.1 GBq (5.26-16.25 GBq) for single administrations; Lu-DOTATATE was 7.2 GBq (2.5-7.5 GBq); and I-NaI was 3 GBq for thyroid remnant ablation and 5.5 GBq for cancer therapy. The median number of comforters and carers for all administrations was 2 (range 1-9). The median exposure values for comforters and carers for high-administered activity I-mIBG administrations was 302 µSv (0-5282 µSv); for single fraction I-mIBG 163 µSv (3-3104 µSv); Lu-DOTATATE 6 µSv (1-79 µSv); and I-NaI 37 µSv (0-274 µSv). Only one of the comforters and carers exceeded the dose constraint of 5 mSv.

Conclusions: Doses to comforters and carers were in all but one case within the dose constraint nationally recommended by the Health Protection Agency, now part of Public Health England. New evidence is presented which show that comforter and carer radiation exposure levels from paediatric molecular radiotherapy in routine clinical practice are acceptably low. Pediatr Blood Cancer 2015;62:235-239. © 2014 Wiley Periodicals, Inc.