Presentation Authors: Muammer Altok, Brian Chapin, Surena Matin, Mary Achim, John Davis*, Houston, TX
Introduction: Patients with low to favorable intermediate risk prostate cancer (or using a nomogram) may be selected for a radical prostatectomy treatment without a lymph node dissection. However, some patients may then experience upgrading or upstaging above such threshold--a term we have given &[Prime]Nx Regret.&[Prime] In this study, we explore the hypothesis that patients with Nx Regret pathology experience the same vs different biochemical relapse relate compared with a matched cohort of pN0/N1 selected cases.
Methods: The patient population is from an NCI designated comprehensive cancer center with multi-surgeon, high-volume experience in robotic prostatectomy and extended lymphadenectomy. Patients studied were treated from 2006-2012 to allow sufficient PSA follow-up. We constructed the study cohort of 521 pNx and 505 pN0/N1 patients with biopsy Gleason score 3+4 and cT1c-cT2. Cohorts were compared unadjusted and then with propensity score matching.
Results: Gleason upgrading from 3+4 to RP Gleason grade >3+4 and/or pT3-4 was observed in 17% of pNx (Nx Regret) and in 32% of pN0/N1 (p < 0.001). BCR occurred in 5% in the Nx, and 7% in the PLND group. Five-year BCR free survival rate was higher in the Nx group (94.7% vs. 91%, p = 0.048). In the pNx group, Nx Regret and non-Nx Regret were compared. BCR occurred in 3% in the non-Nx Regret and 18% in the Nx Regret patients. Five-year BCR free survival rate was higher in the Non-Nx Regret group (98% vs. 81%, p < 0.001). Finally, Nx Regret was compared with propensity score matched PLND (N0/N1) patients. Five-year BCR free survival rate was detected similar between groups (81% vs. 83%, p = 0.467, Fig.1).
Conclusions: When low to favorable intermediate risk patients are selected for no PLND and experience upgrading or upstaging, they have a higher predicted BCR. However, when matched to similar patients with pN0/N1, the BCR was not different. We did not identify a testable hypothesis that the PLND adds therapeutic value in this patient group.
Source of Funding: This study was supported in part by Cancer Center Core Grant (P30CA 16672) from the University of Texas MD Anderson Cancer Center.