Division of Radiation Oncology, San Bortolo Hospital, Viale Rodolfi 37, 36100 Vicenza, Italy.
Technol Cancer Res Treat. 2010 Oct;9(5):473-7. doi: 10.1177/153303461000900505.
Stereotactic body radiotherapy (SBRT) is a new treatment modality for prostate cancer. The current study evaluates CyberKnife SBRT and reports toxicity and early Prostate-Specific Antigen (PSA) kinetics. From June 2006 to August 2009, 45 low-and intermediate-risk prostate cancer patients received Cyberknife SBRT of 35 Gy in five fractions with 95% minimum target coverage. Median follow-up was 20-months (range 6-42-months). Seventeen patients received androgen-deprivation therapy also. Acute complications were mild, short-lived and no greater than Grade 2 by RTOG scale. Late toxicities consisted of one patient (2.2%) experiencing Grade 2 rectal, one patient (2.2%) Grade 3 and four patients (8.8%) with Grade 1 urinary toxicity. PSA in all patients progressively declined from a mean 4.7 ng/ml baseline to 1.48 ng/ml at three months, to 0.68 ng/ml at 12 months and to 0, 35 ng/ml at 24 months. The 28 hormon-naive patients had the mean PSA value of 1.1 ng/ml at one year from a mean 6.65 ng/ml baseline. There was a significant PSA value reduction in 11 hormone therapy patients with low baseline PSA value (< or = 1 ng/ml) from 0.37 down 0.14 ng/ml (p value 0.0068) at one year. Moreover, 14 low risk patients gave better results of mean PSA value than 17 Intermediate risk patients 0.43 ng/ml vs. 0.93 ng/ml (p value 0.02) at one year. No patient had biochemical failure at last follow-up. Hypofractionated SBRT appears to have potential against prostate cancer. Low toxicity and encouraging biochemical control support its use in early-stage prostate cancer. Results encourage further follow-up and larger studies.
立体定向体部放射治疗（SBRT）是一种新的前列腺癌治疗方法。本研究评估了 CyberKnife SBRT，并报告了毒性和早期前列腺特异性抗原（PSA）动力学。从 2006 年 6 月至 2009 年 8 月，45 例低危和中危前列腺癌患者接受了 Cyberknife SBRT，35Gy 分 5 次给予，95%最小靶区覆盖率。中位随访时间为 20 个月（范围 6-42 个月）。17 例患者还接受了雄激素剥夺治疗。急性并发症轻微，持续时间短，根据 RTOG 量表不超过 2 级。晚期毒性包括 1 例（2.2%）患者发生 2 级直肠毒性，1 例（2.2%）患者发生 3 级和 4 例（8.8%）患者发生 1 级尿毒性。所有患者的 PSA 均从基线的平均 4.7ng/ml 逐渐下降至 3 个月时的 1.48ng/ml，12 个月时的 0.68ng/ml，至 24 个月时的 0、35ng/ml。28 例无激素治疗的患者在 1 年时从基线的平均 6.65ng/ml 降至平均 PSA 值 1.1ng/ml。11 例基线 PSA 值较低（<或=1ng/ml）的激素治疗患者 PSA 值显著降低，从 0.37 降至 0.14ng/ml（p 值=0.0068）。此外，14 例低危患者的 PSA 值平均水平优于 17 例中危患者（0.43ng/ml 与 0.93ng/ml，p 值=0.02）。末次随访时无生化失败患者。低分割 SBRT 对前列腺癌有一定的疗效。低毒性和令人鼓舞的生化控制支持其在早期前列腺癌中的应用。结果鼓励进一步随访和更大规模的研究。
