Prognostic Value of Local Treatment in Prostate Cancer Patients With Different Metastatic Sites: A Population Based Retrospective Study

Purpose Our study aims to examine the impact of definitive local therapy in prostate cancer patients with different metastatic sites. Methods Totally, 5,849 patients diagnosed with metastatic prostate carcinoma from 2010 to 2014 were selected from Surveillance, Epidemiology, and End Results (SEER). Log-rank analyses, multivariable regression analysis, and Kaplan-Meier methods were used to assess prognostic impact of local treatment in patients with different metastatic sites. Survival curves and forest plots were also plotted to describe the prognostic value of definitive local therapy. Results In our study, 159 patients received radical prostatectomy, and 62 received brachytherapy, while 5,628 did not receive local definitive local therapy. Survival analysis revealed that patients who received definitive local therapy had a better 5-year overall survival (OS) (P = 0.011) and cancer-specific survival (CSS) (P = 0.012). Multivariate regression analyses demonstrated that type of treatment was an independent prognostic indicator for OS (P = 0.011) and CSS (P = 0.012), along with age at diagnosis, chemotherapy, PSA level, and Gleason score. According to subgroup analysis, patients with bone metastasis or distant lymph node (LN) metastasis were significantly more likely to benefit from definitive local therapy. In addition, forest plots demonstrated that RP group had significant favorable OS and CSS in subgroups of younger age at diagnosis, T2-3 stage, N0-1 stage, Gleason score =7 or >= 8, bone metastasis, and distant LN metastasis. Conclusions Our study suggested that local therapy improved survival in prostate cancer patients with bone or distant LN metastasis. Furthermore, patients who were at T2-3 stage or Gleason score >= 7 also significantly benefit from definitive local therapy.