Schild Michael H, Schild Steven E, Wong William W, Vora Sujay A, Keole Sameer R, Vargas Carlos E, Daniels Thomas B, Ezzell Gary A, Nguyen Ba D, Roarke Michael C
Midwestern University, Glendale, Arizona.
Department of Radiation Oncology, Mayo Clinic Hospital, Phoenix, Arizona.
Int J Radiat Oncol Biol Phys. 2017 Apr 1;97(5):1021-1025. doi: 10.1016/j.ijrobp.2017.01.219. Epub 2017 Feb 1.
This report describes the long-term outcomes of a prospective trial of intensity modulated radiation therapy (IMRT), integrating a In capromab pendetide (ProstaScint) scan-directed simultaneous integrated boost (SIB) for localized prostate cancer.
Seventy-one patients with T1N0M0 to T4N0M0 prostate cancer were enrolled, and their ProstaScint and pelvic computed tomography scans were coregistered for treatment planning. The entire prostate received 75.6 Gy in 42 fractions with IMRT, whereas regions of increased uptake on ProstaScint scans received 82 Gy as an SIB. Patients with intermediate- and high-risk disease also received 6 months and 12 months of adjuvant hormonal therapy, respectively.
The study enrolled 31 low-, 30 intermediate-, and 10 high-risk patients. The median follow-up was 120 months (range, 24-150 months). The 10-year biochemical control rates were 85% for the entire cohort and 84%, 84%, and 90% for patients with low-, intermediate-, and high-risk disease, respectively. The 10-year survival rate of the entire cohort was 69%. Pretreatment prostate-specific antigen level >10 ng/mL and boost volume of >10% of the prostate volume were significantly associated with poorer biochemical control and survival. The outcomes were compared with those of a cohort of 302 patients treated similarly but without the SIB and followed up for a median of 91 months (range, 6-138 months). The 5- and 10-year biochemical control rates were 86% and 61%, respectively, in patients without the SIB compared with 94% and 85%, respectively, in patients in this trial who received the SIB (P=.02). The cohort that received an SIB did not have increased toxicity.
The described IMRT strategy, integrating multiple imaging modalities to administer 75.6 Gy to the entire prostate with a boost dose of 82 Gy, was feasible. The addition of the SIB was associated with greater biochemical control but not toxicity. Modern imaging technology can be used to locally intensify the dose to tumors and spare normal tissues, producing very favorable long-term biochemical disease control.
本报告描述了一项前瞻性试验的长期结果，该试验采用调强放射治疗（IMRT），结合锝[99mTc] 卡妥索单抗（ProstaScint）扫描引导下的同步整合加量照射（SIB）治疗局限性前列腺癌。
纳入71例T1N0M0至T4N0M0前列腺癌患者，将他们的ProstaScint扫描和盆腔计算机断层扫描进行配准以用于治疗计划。整个前列腺通过IMRT接受42次分割、总量75.6 Gy的照射，而ProstaScint扫描上摄取增加的区域作为SIB接受82 Gy的照射。中危和高危疾病患者还分别接受了6个月和12个月的辅助激素治疗。
该研究纳入了31例低危、30例中危和10例高危患者。中位随访时间为120个月（范围24 - 150个月）。整个队列的10年生化控制率为85%，低危、中危和高危疾病患者的10年生化控制率分别为84%、84%和90%。整个队列的10年生存率为69%。治疗前前列腺特异性抗原水平>10 ng/mL以及加量体积>前列腺体积的10%与较差的生化控制和生存率显著相关。将这些结果与一组302例接受类似治疗但未进行SIB且中位随访时间为91个月（范围6 - 138个月）的患者的结果进行比较。未进行SIB的患者5年和10年生化控制率分别为86%和61%，而本试验中接受SIB的患者分别为94%和85%（P = 0.02）。接受SIB的队列未出现毒性增加。
所描述的IMRT策略，即整合多种成像方式对整个前列腺给予75.6 Gy照射并加量至82 Gy，是可行的。添加SIB与更好的生化控制相关，但与毒性无关。现代成像技术可用于局部增加肿瘤剂量并保护正常组织，从而产生非常良好的长期生化疾病控制效果。
