Dubinsky Pavol, Vojtek Vladimir, Belanova Katarina, Janickova Natalia, Balazova Noemi, Tomkova Zuzana
Department of Radiation Oncology, East Slovakia Institute of Oncology, 041 91 Kosice, Slovakia.
Faculty of Health, Catholic University in Ruzomberok, 034 01 Ruzomberok, Slovakia.
Life (Basel). 2023 Jul 23;13(7):1610. doi: 10.3390/life13071610.
The optimal hypofractionated schedule of post-prostatectomy radiotherapy remains to be established. We evaluated treatment outcomes and toxicity of moderately hypofractionated post-prostatectomy radiotherapy in 16 daily fractions delivered with intensity-modulated radiotherapy. The treatment schedule selection was motivated by limited technology resources and was radiobiologically dose-escalated.
One hundred consecutive M0 patients with post-prostatectomy radiotherapy were evaluated. Radiotherapy indication was adjuvant (ART) in 19%, early-salvage (eSRT) in 46% and salvage (SRT) in 35%. The dose prescription for prostate bed planning target volume was 52.8 Gy in 16 fractions of 3.3 Gy. The Common Terminology Criteria v. 4 for Adverse Events scale was used for toxicity grading.
The median follow-up was 61 months. Five-year biochemical recurrence-free survival (bRFS) was 78.6%, distant metastases-free survival (DMFS) was 95.7% and overall survival was 98.8%. Treatment indication (ART or eSRT vs. SRT) was the only significant factor for bRFS (HR 0.15, 95% CI 0.05-0.47, = 0.001) and DMFS (HR 0.16, 95% CI 0.03-0.90; = 0.038). Acute gastrointestinal (GI) toxicity grade 2 was recorded in 24%, grade 3 in 2%, acute genitourinary (GU) toxicity grade 2 in 10% of patients, and no grade 3. A cumulative rate of late GI toxicity grade ≥ 2 was observed in 9% and late GU toxicity grade ≥ 2 in 16% of patients.
The observed results confirmed efficacy and showed a higher than anticipated rate of early GI, late GI, and GU toxicity of post-prostatectomy radiobiologically dose-escalated hypofractionated radiotherapy in 16 daily fractions.
前列腺切除术后放疗的最佳低分割方案仍有待确定。我们评估了采用调强放疗分16次每日照射的中度低分割前列腺切除术后放疗的治疗效果和毒性。该治疗方案的选择是受技术资源有限所驱动，并且在放射生物学上进行了剂量递增。
对连续100例接受前列腺切除术后放疗的M0患者进行评估。放疗适应证为辅助放疗（ART）的占19%，早期挽救性放疗（eSRT）的占46%，挽救性放疗（SRT）的占35%。前列腺床计划靶体积的剂量处方为52.8 Gy，分16次，每次3.3 Gy。采用不良事件通用术语标准第4版进行毒性分级。
中位随访时间为61个月。5年生化无复发生存率（bRFS）为78.6%，远处转移无复发生存率（DMFS）为95.7%，总生存率为98.8%。治疗适应证（ART或eSRT与SRT相比）是bRFS（风险比0.15，95%置信区间0.05 - 0.47，P = 0.001）和DMFS（风险比0.16，95%置信区间0.03 - 0.90；P = 0.038）的唯一显著因素。24%的患者记录有2级急性胃肠道（GI）毒性，2%有3级；10%的患者有2级急性泌尿生殖系统（GU）毒性，无3级。9%的患者观察到累积≥2级晚期GI毒性发生率，16%的患者观察到≥2级晚期GU毒性发生率。
观察结果证实了疗效，并显示出在16次每日照射的前列腺切除术后放射生物学剂量递增的低分割放疗中，早期GI、晚期GI和GU毒性发生率高于预期。
