Kimura Takahiro, Kido Masahito, Miki Kenta, Yamamoto Toshihiro, Sasaki Hiroshi, Kuruma Hidetoshi, Hayashi Norihiro, Takahashi Hiroyuki, Aoki Manabu, Egawa Shin
Department of Urology, Jikei University School of Medicine, Tokyo, Japan.
Int J Urol. 2014 May;21(5):473-8. doi: 10.1111/iju.12347. Epub 2013 Nov 20.
To analyze mid-term oncological outcomes of low-dose rate brachytherapy in Japanese patients.
Between 2003 and 2010, 604 consecutive patients with clinically localized prostate cancer were treated with low-dose rate brachytherapy at Jikei University Hospital in Tokyo, Japan. Median follow up was 48 months. Of these patients, 260 (43%) were treated with neoadjuvant therapy, 45 (7.5%) with adjuvant hormonal therapy and 75 (12.4%) with supplemental external beam radiation therapy. Biochemical recurrence was defined as the prostate-specific antigen nadir plus 2 ng/mL.
Of the 604 patients, 219 (36.2%) were low risk, 361 (59.8%) were intermediate risk and 24 (4.0%) had high-risk disease. The median biologically effective dose was 174.4 Gy2. At 8 years, biochemical recurrence-free survival, cancer-specific survival, and overall survival were 82.2%, 100% and 95.6%, respectively. Biochemical recurrence-free survival at 8 years was 89.9%, 79.4% and 52.5%, for the low-, intermediate-, and high-risk groups, respectively. Biochemical recurrence-free survival for the high-risk group was significantly lower than the low- and intermediate-risk groups (P < 0.001). Biochemical recurrence-free survival did not differ significantly by biologically effective dose stratification. In multivariate analysis, younger age (P = 0.045), higher prostate-specific antigen (P = 0.004), higher Gleason score (P = 0.006) and higher clinical T stage (P = 0.008) were significant covariates associated with biochemical recurrence. The addition of hormonal therapy or external beam radiation therapy was associated with significantly better outcomes than low-dose rate brachytherapy monotherapy (P = 0.0021 and 0.010). Just four patients experienced G3 genitourinary or gastrointestinal toxicity.
Low-dose rate brachytherapy results in excellent mid-term oncological outcomes and acceptable toxicity in Japanese patients. In our experience, biologically effective dose does not represent a significant predictor for biochemical recurrence.
分析日本患者接受低剂量率近距离放射治疗的中期肿瘤学结果。
2003年至2010年期间，日本东京慈惠会医科大学医院对604例临床局限性前列腺癌患者连续进行了低剂量率近距离放射治疗。中位随访时间为48个月。在这些患者中，260例（43%）接受了新辅助治疗，45例（7.5%）接受了辅助激素治疗，75例（12.4%）接受了补充外照射放疗。生化复发定义为前列腺特异性抗原最低点加2 ng/mL。
604例患者中，低危患者219例（36.2%），中危患者361例（59.8%），高危患者24例（4.0%）。中位生物等效剂量为174.4 Gy2。8年时，生化无复发生存率、癌症特异性生存率和总生存率分别为82.2%、100%和95.6%。低危、中危和高危组8年时的生化无复发生存率分别为89.9%、79.4%和52.5%。高危组的生化无复发生存率显著低于低危和中危组（P < 0.001）。生化无复发生存率在生物等效剂量分层中无显著差异。多因素分析显示，年龄较小（P = 0.045）、前列腺特异性抗原水平较高（P = 0.004）、Gleason评分较高（P = 0.006）和临床T分期较高（P = 0.008）是与生化复发相关的显著协变量。添加激素治疗或外照射放疗的结果明显优于低剂量率近距离放射治疗单一疗法（P = 0.0021和0.010）。仅有4例患者出现3级泌尿生殖系统或胃肠道毒性。
低剂量率近距离放射治疗在日本患者中产生了优异的中期肿瘤学结果和可接受的毒性。根据我们的经验，生物等效剂量并非生化复发的显著预测因素。
