Radiation Oncology, Salamanca University Hospital, Paseo de San Vicente, 182, 37007, Salamanca, Spain,
Clin Transl Oncol. 2014 Apr;16(4):380-5. doi: 10.1007/s12094-013-1089-y. Epub 2013 Aug 9.
Single-institution single-arm prospective study. Endpoint: To assess whether there are more than 5 % of men having grade 3 GU or any grade 3 GI acute toxicity during stereotactic body radiation therapy (SBRT) for prostate cancer using helical tomotherapy.
Since May 2012, 17 prostate cancer patients were treated with helical tomotherapy. The exclusion criteria used are the following: Gleason score ≥8, PSA >20 ng/ml, cT3b-4, IPSS ≥20 and history of acute urinary retention. CTV included the prostate gland and 1 cm of seminal vesicles in the low-risk group (LR) or the seminal vesicles completely in the intermediate (IR) and high-risk (HR) NCCN groups. CTV margins ranged from 2 to 8 mm, while PTV margins were 2 to 9 mm. Patients received eight fractions of 5.48 Gy (LR) or 5.65 Gy (IR, HR) on alternate days. Total equivalent doses at 2 Gy per fraction are 87.4 for LR and 92.3 Gy for IR-HR using an α/β value of 1.5. Correspondent figures for a α/β of 3 are 74.3 Gy and 78.2 Gy, respectively. Megavoltage CT (MVCT) for on-line correction was taken before every fraction.
The patient distribution by risk group is 29, 47 and 24 % for LR, IR and HR, respectively. 82 % received neoadjuvant-concomitant hormonal therapy. Acute GU toxicity grade 1, 2 and 3 was found in 70, 6 and 0 % of men. GI toxicity was observed in 50, 0 and 0. After 136 MVCT, the standard deviation of the mean individual corrections in the anterior-posterior direction was 2.5 mm.
SBRT for prostate cancer using helical tomotherapy is feasible. Initial results show an early toxicity profile no worse than SBRT delivered with robotic radiosurgery or conventionally fractionated radiotherapy.
单机构单臂前瞻性研究。终点：评估使用螺旋断层放疗（tomotherapy）治疗前列腺癌时，是否有超过 5%的男性出现 3 级 GU 或任何 3 级 GI 急性毒性。
自 2012 年 5 月以来，17 例前列腺癌患者接受了螺旋断层放疗。使用的排除标准如下：Gleason 评分≥8、PSA>20ng/ml、cT3b-4、IPSS≥20 和有急性尿潴留病史。CTV 包括低危组（LR）的前列腺和 1cm 精囊，或中危（IR）和高危（HR）NCCN 组的精囊完全。CTV 边缘为 2-8mm，PTV 边缘为 2-9mm。患者隔日接受 8 次 5.48Gy（LR）或 5.65Gy（IR、HR）的治疗。使用 α/β 值为 1.5 时，LR 的 2Gy 等效剂量为 87.4Gy，IR-HR 的为 92.3Gy。当 α/β 值为 3 时，相应的数字分别为 74.3Gy 和 78.2Gy。每次分割前都进行兆伏 CT（MVCT）在线校正。
按风险组分布，LR、IR 和 HR 分别为 29%、47%和 24%。82%的患者接受了新辅助同期激素治疗。70%、6%和 0%的男性出现急性 GU 毒性 1、2 和 3 级。50%、0%和 0%的男性出现 GI 毒性。136 次 MVCT 后，前后方向平均个体校正的标准差为 2.5mm。
使用螺旋断层放疗治疗前列腺癌是可行的。初步结果显示，早期毒性与机器人放射外科或常规分割放疗的 SBRT 相比没有恶化。
