Biochemical relapse free survival rate in patients with prostate cancer treated with external radiotherapy: outcomes obtained at the CMN Siglo XXI Hospital de Oncología, CMN 20 de Noviembre and Hospital General de México of the México City

Heuristic estimation of the α/β ratio for a cohort of Mexican patients with prostate cancer treated with external radiotherapy techniques

“…The bRFS rates are obtained and characterized with the Kaplan-Meier technique for a cohort of Mexican patients (nTotal = 595) with PCa who received treatment with external radiotherapy [19], see Table 1. This research confirms that the rates of bRFS are statistically equivalent within the cohort of Mexican patients with respect to the treatments.…”

“…Thus, due to the fact that our treatment schemes are radiobiologically equivalent [19], the α/β is determined for the different treatment schemes with the BED calculated with Eq. (4) under the former hypothesis and the assumption that the doubling time Td = 50 days and an accelerated repopulation time Tk = 30 days, which correspond to k = 0.1 Gy/day recommended by Khan [23].…”

“…To summarize and reiterate with pedagogical purposes: the treatment schemes published by Adame et al are radiobiologically equivalent [19], the α/β's are determined using the reported bRFS's and calculated BED's. with Eq.…”

“…The testing took place in three separate hospital institutions located in Mexico City. The RT techniques used in these patients were three-dimensional conformal radiation therapy (3D-CRT), intensitymodulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) [19]. The biochemical relapse-free survival (bRFS) values obtained in the study are taken as a reference to perform a radiobiological optimization [19].…”

“…The RT techniques used in these patients were three-dimensional conformal radiation therapy (3D-CRT), intensitymodulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) [19]. The biochemical relapse-free survival (bRFS) values obtained in the study are taken as a reference to perform a radiobiological optimization [19]. These values are also used to determine the α/β for the Mexican population by which the heuristic Pedicini's method is used [20].…”