Impact of local treatment on overall survival of patients with metastatic prostate cancer: systematic review and meta-analysis

ABSTRACT Context Currently, standard treatment of metastatic prostatic cancer (MPCa) is androgen-deprivation therapy (ADT). Recent studies suggested that local treatment of MPCa is related to increase of survival of those patients, as observed in other tumors. Objective To evaluate the impact of local treatment on overall survival and cancer specific survival in 3 and 5 years in patients with MPCa. Materials and Methods Systematic review and meta-analysis of population studies published at PubMed, Scielo, Lilacs, Cochrane and EMBASE databases until June 2016. Several large cohorts and Post-Roc studies were included, that evaluated patients with MPCa submitted to local treatment (LT) using radiotherapy (RDT), surgery (RP) or brachytherapy (BCT) or not submitted to local treatment (NLT). Results 34.338 patients were analyzed in six included papers, 31.653 submitted to NLT and 2.685 to LT. Overall survival in three years was significantly higher in patients submitted to LT versus NLT (64.2% vs. 44.5%; RD 0.19, 95% CI, 0.17-0.21; p<0.00001; I2=0%), as well as in five years (51.9% vs. 23.6%; RD 0.30, 95% CI, 0.11-0.49; p<0.00001; I2=97%). Sensitive analysis according to type of local treatment showed that surgery (78.2% and 45.0%; RD 0.31, 95% CI, 0.26-0.35; p<0.00001; I2=50%) and radiotherapy (60.4% and 44.5%; RD 0.17, 95% CI, 0.12-0.22; p<0.00001; I2=67%) presented better outcomes. Conclusion LT using RDT, RP or BCT seems to significantly improve overall survival and cancer-specific survival of patients with metastatic prostatic cancer. Prospective and randomized studies must be performed in order to confirm our results.

摘要

## 研究背景
当前，转移性前列腺癌（metastatic prostatic cancer, MPCa）的标准治疗方案为雄激素剥夺疗法（androgen-deprivation therapy, ADT）。既往研究表明，正如其他肿瘤中所观察到的结果一样，转移性前列腺癌的局部治疗可提升患者的生存期。
## 研究目的
评估局部治疗对转移性前列腺癌患者3年及5年总生存期与癌症特异性生存期的影响。
## 材料与方法
对截至2016年6月发表于PubMed、Scielo、Lilacs、Cochrane及EMBASE数据库的人群研究进行系统评价与荟萃分析。本研究纳入多项大型队列研究及Post-Roc研究，评估接受局部治疗（local treatment, LT）的转移性前列腺癌患者，局部治疗方式包括放疗（radiotherapy, RDT）、手术（surgery, RP）或近距离放射治疗（brachytherapy, BCT），并以未接受局部治疗（non-local treatment, NLT）作为对照。
## 研究结果
共纳入6篇文献，分析患者共计34338例，其中31653例接受NLT，2685例接受LT。LT组患者的3年总生存率显著高于NLT组（64.2% vs. 44.5%；风险差RD=0.19，95%置信区间CI：0.17~0.21；p<0.00001；I²=0%），5年总生存率亦呈现类似结果（51.9% vs. 23.6%；RD=0.30，95%CI：0.11~0.49；p<0.00001；I²=97%）。按局部治疗类型进行的敏感性分析显示，手术组（78.2%与45.0%；RD=0.31，95%CI：0.26~0.35；p<0.00001；I²=50%）与放疗组（60.4%与44.5%；RD=0.17，95%CI：0.12~0.22；p<0.00001；I²=67%）均获得更优的治疗结局。
## 研究结论
采用放疗（RDT）、手术（RP）或近距离放射治疗（BCT）的局部治疗，可显著改善转移性前列腺癌患者的总生存期与癌症特异性生存期。未来需开展前瞻性随机对照研究以验证本研究结论。