Survival outcomes of low prostate-specific antigen levels and T stages in patients with high-grade prostate cancer: a population-matched study

Objective: To evaluate the prostate cancer-specific survival (PCSS) of low T stages or low prostate-specific antigens (PSA) levels in men with high-grade prostate cancer. Materials and Methods: Patients with non-metastatic prostate cancer (T1-4N0M0) and Gleason score 8-10 in the Surveillance, Epidemiology, and End Results database from 2004-2010 were identified. These men were stratified by T stages (T1, T2, T3a, T3b-4) and PSA levels (<4.0 ng/ml, 4.0-10.0 ng/ml, 10.1-20.0 ng/ml, >20.0 ng/ml). Propensity-score matching (PSM) was conducted to balance the covariates. Kaplan-Meier analysis and multivariable Cox regressions were performed to analyze the PCSS in different T stage or PSA levels groups. Results: A total of 33231 patients aging 69(62~76) years were identified. The overall cohort results showed that the PCSS of T1 group was significantly worse than that of T2 and T3a groups [T2 HR: 0.62(0.57~0.67); T3 HR: 0.70(0.63~0.77)]. There were no significant difference between T2 and T3a groups [T2 HR: 0.98 (0.91~1.05)]. The PSA <4.0 ng/ml group had significantly worse PCSS than PSA 4.0-10.0 ng/ml [PSA 4.0-10.0 ng/ml HR: 0.77(0.68~0.88)]. PSM methods were implemented in the comparison of T1 vs T2, T1 vs T3a, T2 vs T3a. and PSA< 4.0 ng/ml vs PSA 4.0-10.0 ng/ml, The results in these matched cohorts showed that T1 group was associated with significantly worse PCSS than T2 group [T1 HR: 1.31(1.20~1.44)] and T3a group [T1 HR: 1.33(1.16~1.52)]. There were no significant differences between T2 and T3a groups [T3a HR: 1.14(0.99~1.32)]. The PCSS of patients with PSA< 4.0 ng/ml was significantly worse that these with PSA 4.0-10.0 ng/ml in the matched cohort [PSA< 4.0 ng/ml HR: 1.3(1.08~1.56)]. Conclusions: For patients with high-grade PCa, the PCSS of patients seems to be worse in the T1 stage than those in T2 and T3a stages. Patients with PSA <4.0 ng/ml appears to have poorer prognosis than those with PSA 4.0-10.0 ng/ml.