Variation in Positive Surgical Margin Status After Radical Prostatectomy for pT2 Prostate Cancer

We evaluated patient, hospital, and cancer-specific factors associated with positive surgical margin (PSM) variability after radical prostatectomy in pT2 prostate cancer in the United States.

A total of 45,426 men from 1152 hospitals with pT2 prostate cancer and known margin status after radical prostatectomy were identified using the National Cancer Database (2010-2015). Data on patient, cancer, hospital factors, and surgical approach were extracted. A mixed effects logistic regression model was computed to examine factors associated with PSM and partial R² values to assess the relative contributions of patient, cancer, and hospital variables to PSM status.

Median PSM rate of 8.5% (interquartile range, 5.2%-13.0%). Robotic (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.83-0.99) and laparoscopic (OR, 0.74; 95% CI, 0.64-0.90) surgical approach, academic institution (OR, 0.87; 95% CI, 0.76-1.00) and high hospital surgical volume (>297 cases [OR], 0.83; 95% CI, 0.70-0.99) were independently associated with a lower PSM. Black men (OR, 1.13; 95% CI, 1.01-1.26) and adverse cancer-specific features (prostate-specific antigen [PSA], 10-20; PSA >20; cT3 stage; Gleason 7, 8, 9-10; all P > .01) were independently associated with a higher PSM. Patient-specific, hospital-specific, and cancer-specific factors had a contribution of 2.3%, 3.9%, and 15.2%, respectively, to the variation in PSM. Facility had a contribution of 23.7% to the variation in PSM.

Cancer-specific factors account for 15.2% of PSM variation with the remaining 84.8% of PSM variation due to patient, hospital, and other factors not accounted within the model. Noncancer-specific factors represent addressable factors that are important for policy-makers in efforts to improve patient outcome.