Arcangeli Stefano, Strigari Lidia, Soete Guy, De Meerleer Gert, Gomellini Sara, Fonteyne Valerie, Storme Guy, Arcangeli Giorgio
Departments of Radiotherapy, Regina Elena National Cancer Institute, Rome, Italy.
Int J Radiat Oncol Biol Phys. 2009 Jan 1;73(1):39-45. doi: 10.1016/j.ijrobp.2008.04.005. Epub 2008 Jun 4.
To investigate predictors for gastrointestinal (GI) and genitourinary (GU) acute toxicity after a short-course hypofractionated radiotherapy regimen for prostate cancer.
Three institutions included 102 patients with T1-T3N0M0 prostate cancer in a Phase II study. Patients were treated with 56 Gy in 16 fractions over 4 weeks. Acute toxicity was scored weekly during treatment and 1 and 2 months after treatment using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria extended with additional symptoms and the International Prostate Symptom Index (IPSS). Correlation with a number of clinical and dosimetric parameters was assessed by univariate and multivariate analyses.
No Grade 3 or 4 GI side effects were observed. Grades 1 and 2 rectal GI toxicity occurred in 36%, and 38%, respectively. Corresponding figures for Grades 1 and 2 GU toxicity were 42% and 39%, respectively. Grade 3 or higher GU toxicity was detected in 4% of patients. In multivariate analysis, percent rectal volumes higher than 8% receiving doses >/=53 Gy (V(53)) were statistically correlated to Grade 2 acute rectal reaction (p = 0.006). For GU morbidity, only the IPSS pretreatment score was independently associated (p = 0.0036) with an increase in GU acute effects.
Acute GU and GI toxicity were comparable with other series. Our data show that increased incidence and intensity of acute toxicity is a transient effect related to shorter overall treatment time rather than a larger effect in biological equivalent dose with respect to a conventional fractionation regime.
探讨前列腺癌短程大分割放疗方案后胃肠道（GI）和泌尿生殖系统（GU）急性毒性的预测因素。
三家机构在一项II期研究中纳入了102例T1-T3N0M0前列腺癌患者。患者在4周内分16次接受56 Gy的治疗。在治疗期间以及治疗后1个月和2个月，使用扩展了额外症状的放射治疗肿瘤学组/欧洲癌症研究与治疗组织标准以及国际前列腺症状指数（IPSS）对急性毒性进行每周评分。通过单因素和多因素分析评估与一些临床和剂量学参数的相关性。
未观察到3级或4级胃肠道副作用。1级和2级直肠胃肠道毒性分别发生在36%和38%的患者中。1级和2级泌尿生殖系统毒性的相应数字分别为42%和39%。4%的患者检测到3级或更高等级的泌尿生殖系统毒性。在多因素分析中，接受剂量≥53 Gy（V(53)）且高于8%的直肠体积百分比与2级急性直肠反应在统计学上相关（p = 0.006）。对于泌尿生殖系统发病率，只有IPSS治疗前评分与泌尿生殖系统急性效应增加独立相关（p = 0.0036）。
急性泌尿生殖系统和胃肠道毒性与其他系列相当。我们的数据表明，急性毒性发生率和强度的增加是与较短的总治疗时间相关的短暂效应，而不是相对于传统分割方案在生物等效剂量方面有更大的效应。
