Guirado, DamianRuiz-Arrebola, SamuelTornero-Lopez, Ana Mde la Vega, Jose MPrada, Pedro JLallena, Antonio M2023-02-082023-02-082020-02-23Guirado D, Ruiz-Arrebola S, Tornero-López AM, de la Vega JM, Prada PJ, Lallena AM. A radiobiological study of the schemes with a low number of fractions in high-dose-rate brachytherapy as monotherapy for prostate cancer. J Contemp Brachytherapy. 2020 Apr;12(2):193-200.1689-832Xhttp://hdl.handle.net/10668/15547Schemes with high doses per fraction and small number of fractions are commonly used in high-dose-rate brachytherapy (HDR-BT) for prostate cancer. Our aim was to analyze the differences between published clinical results and the predictions of radiobiological models for absorbed dose required in a single fraction monotherapy HDR-BT. Published HDR-BT clinical results for low- and intermediate-risk patients with prostate cancer were revised. For 13 clinical studies with 16 fractionation schedules between 1 and 9 fractions, a dose-response relation in terms of the biochemical control probability (BC) was established using Monte Carlo-based statistical methods. We obtained a value of α/β = 22.8 Gy (15.1-60.2 Gy) (95% CI) much larger than the values in the range 1.5-3.0 Gy that are usually considered to compare the results of different fractionation schemes in prostate cancer radiotherapy using doses per fraction below 6 Gy. The doses in a single fraction producing BC = 90% and 95% were 22.3 Gy (21.5-24.2 Gy) and 24.3 Gy (23.0-27.9 Gy), respectively. The α/β obtained in our analysis of 22.8 Gy for a range of dose per fraction between 6 and 20.5 Gy was much greater than the one currently estimated for prostate cancer using low doses per fraction. This high value of α/β explains reasonably well the data available in the region of high doses per fraction considered.enAttribution-NonCommercial-ShareAlike 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-sa/4.0/HDR brachytherapymonotherapyprostate cancerHumansMaleBrachytherapyDose Fractionation, RadiationProstatic NeoplasmsProbabilityresearch article32395145open accessBraquiterapiaFraccionamiento de la dosis de radiaciónHumanosMasculinoNeoplasias de la próstataProbabilidad10.5114/jcb.2020.94492PMC7207227https://www.termedia.pl/Journal/-54/pdf-40386-10?filename=A radiobiological study.pdfhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC7207227/pdf