title: Quantifying public radiation exposure related to lutetium-177 octreotate therapy for the development of a safe outpatient treatment protocol.
abstract: OBJECTIVE
  Radionuclide therapies, including treatment of neuroendocrine tumors with lutetium-177 (Lu-177) octreotate, often involve hospital admission to minimize radiation exposure to the public. Overnight admission due to Lu-177 octreotate therapy incurs additional cost for the hospital and is an inconvenience for the patient. This study endeavors to characterize the potential radiation risk to caregivers and the public should Lu-177 octreotate therapies be performed on an outpatient basis.
  
  
  METHODS
  Dose rate measurements of radiation emanating from 10 patients were taken 30 min, 4, and 20 h after initiation of Lu-177 octreotate therapy. Instadose radiation dose measurement monitors were also placed around the patients' rooms to assess the potential cumulative radiation exposure during the initial 30 min-4 h after treatment (simulating the hospital-based component of the outpatient model) as well as 4-20 h after treatment (simulating the discharged outpatient portion).
  
  
  RESULTS
  The mean recorded dose rate at 30 min, 4, and 20 h after therapy was 20.4, 14.0, and 6.6 μSv/h, respectively. The majority of the cumulative dose readings were below the minimum recordable threshold of 0.03 mSv, with a maximum dose recorded of 0.18 mSv.
  
  
  CONCLUSIONS
  Given the low dose rate and cumulative levels of radiation measured, the results support that an outpatient Lu-177 octreotate treatment protocol would not jeopardize public safety. Nevertheless, the concept of ALARA still requires that detailed radiation safety protocols be developed for Lu-177 octreotate outpatients to minimize radiation exposure to family members, caregivers, and the general public.
authors.affiliation: aDepartment of Nuclear Medicine, London Health Sciences Centre, Victoria Campus bDepartment of Medical Imaging, Western University cLawson Health Research Institute, London, Ontario, Canada.
authors.forename: Craig
authors.initials: C
authors.lastname: Olmstead
authors.forename: Kyle
authors.initials: K
authors.lastname: Cruz
authors.forename: Robert
authors.initials: R
authors.lastname: Stodilka
authors.forename: Pamela
authors.initials: P
authors.lastname: Zabel
authors.forename: Robert
authors.initials: R
authors.lastname: Wolfson
mesh_terms: D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D008187:Lutetium / Q000009:adverse effects* / Q000627:therapeutic use; D018358:Neuroendocrine Tumors / Q000532:radiotherapy; D015282:Octreotide / Q000009:adverse effects* / Q000627:therapeutic use; D010045:Outpatients; D011834:Radiation Monitoring; D011868:Radioisotopes / Q000627:therapeutic use*; D012449:Safety; D013997:Time Factors
chemical_list: D011868:Radioisotopes; D008187:Lutetium; D015282:Octreotide