Combined brachytherapy with intermittent hormonal therapy in treating clinical moderate and high risk non-metastatic prostate cancer

Abstract

Objective To investigate the clinical value of 125I particle implantation brachytherapy combined with intermittent hormonal therapy for treating clinical moderate and high risk non-metastatic prostate cancer. Methods A prospective study was proceeded and 100 cases with moderate and high risk(cT≥T2b, Gleason score≥7, pre-biopsy PSA≥10 ng/ml)non-metastatic prostate cancer were included. The selected patients were divided into two group. In the study group, patients were treated with 125I particle implantation combined with intermittent hormonal therapy. In the control group, patients were treated with only intermittent hormonal therapy. Hormonal therapy was maximal androgen blockage for two groups, including bicalutamide 50 mg oral every day and Leuprorelin 3.75 mg subcutaneous injection every 28 days. There were 50 cases in each group and clinical trial agreements were signed. During follow-up, PSA were tested every month. Chest X-ray and whole-body bone scanning were checked every 6 months. Hormonal therapy was stopped when patient's PSA level fell to 0.2 ng/ml, and keep stabilized for 3 months. When PSA level elevated for 3 times continuously and over 1ng/ml, hormonal therapy was initiated again. The IPSS scores were documented before treatment and every 3 months after treatment. Adverse reactions of urinary tract and rectum were assessed every 3 months after 125I particle implantation in study group. The ratio of the first time to stop hormonal therapy, the time duration of first hormonal therapy and stable phase, re-hormonal therapy free survival rate, bone metastasis free survival rate, castration resistance prostate cancer(CRPC) free survival rate, cancer-specific free survival rate and overall survival rate were compared. Results The 100 cases in this study were followed up for 24-40 months, with an average time of 31.6 months. In study group, the PSA level in all cases descended to the level of stopping hormonal therapy. The time duration of hormone therapy ranged from 4 to 12 months, with an average time of 6.3 months. 21 (42%) cases had a PSA elevation again to restart hormonal therapy. In control group, the PSA level in 47 cases descended to the level of stopping hormonal therapy. The time duration of hormone therapy ranged from 5 to 15 months, with an average time of 7.2 months. 34 (68%) cases had a PSA elevation again to restart hormonal therapy. There was no significant difference in percentage of cases of stopping hormone therapy and in time duration of hormonal therapy for the first cycle. Instead, there were significant differences in stable phase after first cycle hormonal therapy between two groups ( 27.2 months vs. 17.7 months; P<0.001). When analyzed by Kaplan-Meier survival curve, there was no significant difference in cancer-specific survival rate and overall survival rate. There were significant differences in Re-hormonal therapy free survival (P=0.002), bone metastasis free survival (P=0.04) and CRPC free survival(P=0.005). Conclusions Compared with intermittent hormonal therapy alone, 125I particle implantation brachytherapy combined with intermittent hormonal therapy could prolong the hormonal sensitive time in moderate and high risk non-metastatic prostate cancer patients and control the progress of the prostate cancer. Key words: Prostaticneoplasms; Brachytherpay; Hormonal therapy