局限期前列腺癌大分割调强放疗临床Ⅱ期研究

Prospective phase Ⅱ trial of hypofractionated intensity-modulated radiotherapy for localized prostate cancer

目的观察前列腺癌2．7Gy25次大分割调强适形放疗的疗效和不良反应。方法2009--2011年52例局限于盆腔的前列腺癌接受前列腺加或不加精囊腺2．7Gy25次（总量67．5Gy）调强放疗，其中20例仅为前列腺加或不加精囊腺照射，32例为前列腺加精囊腺和盆腔淋巴引流区预防照射，盆腔剂量50Gy分25次照射。35例采用了图像引导放疗，48例同时接受内分泌治疗。结果中位随诊13个月，平均前列腺特异抗原由疗前（40．3±36．6）ng／ml降至随诊时的（0．5±1．7）ng／ml。2例治疗失败，其中生化失败1例、盆腔淋巴结复发1例。放疗毒性反应：消化道急性反应2级为25％、3级为4％，泌尿道急性反应2级为15％、3级为2％。消化道晚期损伤2级为17％、3级为0％，泌尿道晚期损伤2级为8％、3级为2％。因大部份病例放疗同时接受了内分泌治疗故无法评价性功能影响。结论局限期前列腺癌大分割调强放疗近期疗效较满意，严重不良反应少见，长期疗效和不良反应有待更长时间随诊评价。

Objective To prospectively evaluate the efficacy and toxicity of hypofractionated intensity-modulated radiotherapy （IMRT） for prostate cancer. Methods Fifty-two consecutive patients with localized prostate cancer were enrolled in this study between Feb. 2009 and Mar. 2011. All patients received hypofractionated IMRT （2.7 Gy/fx, 25 fractions, total 67. 5 Gy） to the prostate and seminal vesicles. 32 high risk patients also received prophylactic irradiation to the pelvic lymph nodes concurrently （2 Gy/fx,25 fractions）. Imaging-guided radiotherapy was employed in 35 patients. Androgen deprivation therapy was adopted in 48 of 52 patients. Results After a median follow-up of 13 months, the mean prostate specific antigen （PSA） was reduced from （40.3 ±36. 6） ng/ml before treatment to （0.5 ± 1.7） ng/ml at the last follow-up. By the time of last follow-up, 2 patients （4%） failed. One had PSA failure and the other had both PSA failure and pelvic lymph node relapse. 25% of the patients experienced grade 2 acute gastrointestinal （GI） toxicity and 4% experienced grade 3 GI toxicity. Acute grade 2 and grade 3 genitourinary （GU） toxicity occurred in 15% and 2%, respectively. The incidence of late grade 2 and grade 3 GI toxicity was 17% and 0% , respectively. Late grade 2 and 3 GU toxicity was 8% and 2%. The potency was unable to evaluate because most of the patients received androgen deprivation therapy . Conclusions The short-term PSA-free survival after 2. 7 Gy/fx,25 fractions＇ hypofraetionated IMRT for localized prostate cancer is favorable, and the acute and late GI and GU toxicity are acceptable. A longer time follow-up is warranted to ascertain the long term efficacy and safety of this regimen.