On the development of consensus values of reference dosimetry parameters for interstitial brachytherapy sources

The American Association of Physicists in Medicine recommends that the reference dose-rate distribution, used for treatment planning for low-energy photon brachytherapy sources in routine clinical use, must be based on at least two independent determinations: one using experimentally measured dose rates and one using Monte Carlo simulation dosimetry techniques. In this work, we present an approach for developing consensus dosimetry parameters from various independent reference dosimetry studies for interstitial brachytherapy sources. This approach is applied to four recently published papers on the dosimetric properties of the BrachySeed Model LS-1 125I seed. Consensus values for the dose-rate constant, radial dose function, and anisotropy parameters are presented for the LS-1 Model 125I seed.