目的：探讨并总结在局限性低/中危前列腺癌患者中采用低剂量率近距离前列腺内放射粒子植入术治疗的有效性及安全性。方法：将133例局限性前列腺癌患者分为低危组和中危组，采用近距离放射性粒子植入术治疗。术后定期进行前列腺特异性抗原（prostatic specific antigen，PSA）及影像学监测，观察术后近、远期并发症并进行分析。结果：本组患者平均术前PSA（13.45±7.1） μg/L，前列腺体积（44.37±21.43） mL，处方放射剂量 （152.0±17.3） Gy。24例初始前列腺体积＞60 mL者术前接受3~6个月新辅助内分泌治疗，低危组与中危组平均年龄、前列腺体积、90%的靶区体积接受的最低剂量（D90）等方面差异均无统计学意义；两组患者国际前列腺症状评分（international prostatic symptomatic score，IPSS）术后第2个月达峰值，术后第4个月后恢复至术前水平；PSA术后第3个月开始回落。研究期间未出现影像学肿瘤进展者，低危组1例、中危组3例随访期间出现生化复发。结论：单纯以近距离内放射粒子植入术治疗早期前列腺癌术后最常见的并发症为下尿路症状，在低危及中危前列腺癌组均可获得较为满意的肿瘤无进展生存。

Objective： To investigate the safety and efficacy of low dose rate brachytherapy in local low and intermediate risk prostate cancer patients. Methods: All 133 local prostate cancer patients were included and divided into low and intermediate risk groups respectively according to Memorial Sloan Kettering Group (MSKG) definition followed by brachytherapy. All the data including prostatic specific antigen (PSA), international prostatic symptomatic score (IPSS), postoperation complications and image evaluation were collected and recorded. Results: The average radiation dose delivered to 90% of the prostate （D90）of (152.0±17.3) Gy was performed in the patients with a mean pre-operation PSA level of (13.45±7.1) μg/L and prostate volume of (44.37±21.43) mL. Neoadjuvant therapy was performed in 24 patients with prostate volume larger than 60 mL for 3-6 months. There was no difference in the mean age, prostate volume and D90 between low risk group and intermediate risk group. The mean IPSS reached its peak at the end of the 2nd month post-brachytherapy and compared with the baseline at the end of the 4th month. PSA failure occurred at the end of the mean 31.7 months in 4 patients during the follow-up (1 in low risk group and 3 in intermediate risk group) and no metastasis occurred.Conclusion:Lower urinary tract symptom (LUTS) is the most common complication post-operation. Brachytherapy associates with an encouraging tumor progress-free survival in local low and intermediate risk prostate cancer patients.