Validation of a nomogram predicting the probability of lymph node invasion based on the extent of pelvic lymphadenectomy in patients with clinically localized prostate cancer

OBJECTIVE: To develop a multivariate nomogram to predict the rate of lymph node invasion (LNI) in patients with clinically localized prostate cancer according to the extent of extended pelvic lymphadenectomy (PLND), which is associated with significantly higher rate of LNI. PATIENTS AND METHODS: The study comprised 781 consecutive patients (median age 66.6 years, range 45-85) treated with PLND and radical retropubic prostatectomy (RRP) for clinically localized prostate cancer. Their median (range) prostate-specific antigen (PSA) level was 7 (1.03-49.91) ng/mL, and their clinical stages were T1c in 433 (55.4%), T2 in 328 (42%) and T3 in 20 (2.6%). Biopsy Gleason sums were