Nationwide survey on the release of ¹³¹I therapy patients to locations other than private residences

Objectives: The Nuclear Regulatory Commission (NRC) has published the regulatory issue summary 2011-01 in 2011 addressing release of patients from the treating facility after their ¹³¹I therapy. We conducted a nationwide survey to characterize the patients who were released to locations other than private residences after their ¹³¹I therapy for differentiated thyroid cancer (DTC).

Methods: A survey was emailed to ~25,000 members of the Thyroid Cancer Survivors’ Association, Inc. that was available online between March-October 2018. Responses were included from DTC patients >18yo who received and evaluated their most recent ¹³¹I therapy between 2011-2018 in the USA and were released to locations other than private residences.

Results: Of the total 2190 responses, 50 (2.3%) respondents stayed at a non-private location after ¹³¹I therapy. The non-private residences included a hotel, motels, boarding house or temporary rental such as Airbnb for 92% (46/50) of patients, and specialized facilities such as cancer care housing in 8% (4/50) of patients. The majority of patients (82%, 41/50) were treated as outpatients, of which two (4%) patients received <30 mCi of ¹³¹I, 12/50 received 30-99 mCi, and 29/50 received 100-499 mCi. Sixty-five percent (31/48) of patients were released within 30 minutes after ¹³¹Iadministration, and 28% (14/50) of patients stayed in hospital for at least one night. Of 31 patients released within 30 minutes to a non-private residence after administration of their ¹³¹I therapy, 12 patients received 100-149 mCi of ¹³¹I, two received 150-199 mCi and one received 250-299 mCi. A subset of these patients answered questions about radiation safety instructions. Ninety percent (45/50) of patients remembered receiving radiation safety instructions. The first radiation safety discussion was held when the ¹³¹I therapy appointment was made (i.e., clinic consultation) in 72% (18/25) of patients, on the day of therapy but before ¹³¹I administration in 24% (6/25) of patients, and after the ¹³¹I therapy in 4%(1/25) of patients. Sixty-eight percent (17/25) of patients were able to discuss and adjust the radiation safety instructions/plans according to their individual situation, and 16% (4/25) of patients stated that they were not given such an opportunity. The radiation safety discussion was held with staff at the ¹³¹I therapy facility in 92% (23/25) of patients, with the referring physician in 48% (12/25), and from DTC patient support groups in 12% (3/25).

Conclusions: We submit that this survey results raise two main concerns regarding radiation safety. First, a significant number of patients were released to a non-private residence within 30 minutes after administration of their ¹³¹I therapy with potentially significant ¹³¹I whole body retention of ¹³¹I. This raises the concern regarding the screening process to ensure that these patients who are going to a non-private residence will not exceed 5 rem exposure to the public. Second, a considerable percentage of patients did not receive radiation safety instructions until the day of ¹³¹I therapy or even after ¹³¹I therapy. This raises the second concern that a significant number of patients may not be receiving their radiation safety instructions early enough to allow time for them to make or modify appropriate travel and lodging plans.