1. Dattoli Cancer Center & Brachytherapy Research Institute, 2803 Fruitville Rd., Sarasota, FL 34237-5367, USA
2. Department of Radiation Oncology and Pathology, University of Washington, Seattle, WA 98195-0001, USA
3. Radiation Oncology, Puget Sound Health Care System, Department of Veterans Affairs, Seattle, WA 98108-1597, USA
4. Group Health Cooperative, Seattle, WA 98124-1590, USA
5. Research Division, Bostwick Laboratories, Richmond, VA 23050-4410, USA