Pathologically Node-Positive Prostate Carcinoma - Prevalence, Pattern of Care and Outcome From a Population-Based Study

To evaluate the prevalence, patterns of care and outcome of pathologically node-positive (pN+) prostate cancer (P-Ca) after radical prostatectomy from a provincial population database.

Patients were identified from a provincial cancer registry and a genitourinary cancer outcomes unit (2005-2014). Of a total of 4723 patients who underwent radical prostatectomy, 167 patients with pN+ P-Ca were identified (28/2181 from 2005-2007 and 139/2542 from 2010-2014). Persistently elevated postoperative prostate-specific antigen (PSA) ≥ 0.2 ng/ml was noted in 52 (31%) patients, 23 (44.2%) of whom had salvage androgen deprivation therapy plus radiotherapy (ADT + RT), 25 (48%) were managed with ADT alone and four (7.8%) had no treatment. Of 115 patients with postoperative PSA <0.2 ng/ml, 47 (41%) had ADT alone and 50 (43.5%) had ADT + RT. Survival estimation was carried out using the Kaplan-Meier method. The association of prognostic factors with survival was evaluated using univariate and multivariate analysis and was limited to the newer cohort (2010-2014).

The median age was 64 years; the median baseline PSA was 12.5 ng/mL (range 2.5-108.4). After a median follow-up of 48 months, overall survival at 5 and 10 years for the entire cohort were 89% and 81%, respectively, and distant metastasis-free survival (DMFS) at the same time points were 77% and 58%, respectively. For the newer cohort, 5-year overall survival and DMFS were 91.5% and 76%, respectively. On univariate analysis, persistently elevated postoperative PSA ≥0.2 ng/ml (P = 0.0003), seminal vesicle involvement (P = 0.027), ≥2 nodes (P = 0.035) and ADT alone (P = 0.054) had a poor prognostic impact on DMFS, whereas margin involvement had a marginally negative influence on overall survival (P = 0.06). On multivariate analysis, postoperative PSA ≥0.2 ng/ml (hazard ratio 4.4, 95% confidence interval 1.7-11.4; P = 0.002) continued to have a significant association with DMFS. On a sensitivity analysis, postoperative PSA ≥0.1 also had a significant association with DMFS on univariate and multivariate analysis (hazard ratio 3.69, 95% confidence interval 1.32-10.29; P = 0.01). Similarly, postoperative PSA ≥0.4 ng/ml had a significant association with DMFS (hazard ratio 3.87, 95% confidence interval 1.58-9.46, P = 0.003).

This study showed a notable difference in the proportion of pN+ P-Ca patients between two different time cohorts. A significant association of persistently elevated postoperative PSA with DMFS was noted in our study. This must be accounted for while tailoring postoperative treatment in pN+ P-Ca.