American Brachytherapy Society recommendations for clinical implementationof NIST-1999 standards for (103)palladium brachytherapy

Purpose: Recent important developments in palladium-103 (Pd-103) dosimetry mandate a reevaluation of Pd-103 brachytherapy prescribing practices. Methods and Materials: The clinical research committee of the American Brac hytherapy Society (ABS) convened a consensus session of brachytherapists an d physicists to develop recommendations regarding future dose prescribing g uidelines for National Institute of Standards and Technology (NIST-1999) ca librated Pd-103 sources, Results: The ABS recommends that clinicians attempt to reproduce the implan t doses delivered and reported in the literature through the past decade, Conclusions: The following should be immediately implemented for Pd-103 dos imetry: 1) All practicing physicians, physicists, dosimetrists, and supplie rs implement NIST-1999 air-kerma strength standard for Pd-103 brachytherapy , 2) All treatment planning systems and dose calculation algorithms must be updated to reflect new dose rate constants. The AAPM-recommended validated value for Theraseed model 200 is 0.665 cGy h(-1) U-1. The dose rate consta nt for the Mentor MED3633 seed is currently reported as 0.68 cGy h(-1) U-1. This latter value and the values for seeds from other manufacturers are aw aiting independent confirmation. 3) Physicians who previously prescribed 11 5 Gy for Pd-103 monotherapy prostate implants should now prescribe 125 Gy, When using Pd-103 as a boost following 45 Gy of external beam irradiation, 100 Gy should be prescribed instead of the previous 90 Gy, It is critical t hat all three changes be implemented concurrently, because they are interde pendent. (C) 2000 Elsevier Science Inc.