Radiation exposure in nurses during care of 131I-MIBG therapy for pediatric patients with high-risk neuroblastoma.

OBJECTIVE

131I-meta-iodo-benzyl-guanidine (131I-MIBG) therapy has been used in children with high-risk neuroblastoma, who, in Japan, are cared for by trained nurses. To determine the safety of occupational radiation exposure in nurses, we retrospectively examined radiation exposure during therapy.

METHODS

Sixty-two nurses who received radiation exposure during 131I-MIBG therapy were assessed for the daily percentage of total radiation exposure received using the formula, daily radiation exposure/total radiation dose × 100; self-care score of children was evaluated.

RESULTS

Fifty-four 131I-MIBG treatments (592 ± 111 MBq/kg) were performed in neuroblastoma patients (M/F; 27 /27, mean age at 131I-MIBG treatment; 7 ± 2 years), who were isolated for 5 ± 1 days. Average total (0.36 ± 0.18 mSv; range 0.09-0.97 mSv) and daily (0.07 ± 0.05 mSv/day; range 0.02-0.32 mSv/day) radiation exposure to nurses per patient care. The daily percentage of total radiation exposure significantly decreased in 3 days after 131I-MIBG treatment (days 0, 1, and 2 was 38.2 ± 14.7%, 26.9 ± 12.6%, and 15.3 ± 7.1%, respectively), and the average self-care score was 12.2 ± 3.5 (10-27) for all patients. Higher self-care score was significantly related to younger patients' age and higher daily radiation exposure in nurses.

CONCLUSION

Individual exposure to radiation was well controlled. Nurses who care for pediatric patients needing daily assistance must be aware of the radiation exposure risks, which can be reduced by establishing a care system and monitoring radiation exposure.