They report it to be accurate.
The EAU nomogram predicts the likelihood of a patient having positive lymph nodes at the time of RP. The EAU PLND guideline recommends a PLND in CaP patients with a nomogram-predicted risk of >7%. The decision to select 7% as the cut-point was based upon a consensus panel of experts. The study sought to validate this cut-point. It included 1,520 patients who underwent PR and PLND between 2006 and 2010, thus representing a contemporary cohort. The PLND was extended, as described by the authors. Four genitourinary pathologists examined PLND tissue in lymph node packets. Average patient age was 64.7 years. Sixty-five percent had PSA levels between 4-10ng/ml. Overall, 10.6% had lymph node invasion (LNI). The rates based upon PSA levels ≤4.0 vs. 4.1-10.0 vs. 10.1-20.0 vs. >20.0ng/ml were 3.7 vs. 8.6 vs. 15.9 vs. 35.9%, respectively. For stages T1 vs. T2 vs. T3 the LNI rates were 5.9 vs. 12.0 vs. 27.3%, respectively. LNI rates were 3.3%, 14.8%, and 39.9% for Gleason scores 2-6, 7, and 8-10, respectively. The average LN counts were 23.1 nodes in those with LNI vs. 18.2 nodes in those with negative LNs.
In the study population of 1,520 patients, 738 (48.6%) were classified below the 7% threshold. They would have avoided a LND according to the EAU guidelines. Positive LN would have been missed in 17 of these men, (10.5% of all patients with confirmed LNI and 2.3% of all patients with avoidable PLND). The most common characteristics for an EAU predicted risk of LNI <7% were PSA 4.1-10ng/ml, clinical stage T1c, and Gleason sum 6. They tested other cut-points and found the 7% clinically reasonable. The AUC for the nomogram was 81.3%. For LNI risk of 0-25%, the nomogram overestimated the rate of LNI by 4.7%. For LNI risk above 25%, the nomogram overestimated the rate of LNI up to 41.7%. They performed the analysis with only patients who had at least 10 LNs removed and found a LNI rate of 11.9% and similar nomogram performance characteristics.
Abdollah F, Sun M, Briganti A, Thuret R, Schmitges J, Gallina A, Suardi N, Capitanio U, Salonia A, Shariat SF, Perrotte P, Rigatti P, Montorsi F, Karakiewicz PI
BJU Int. 2011 Apr 20. Epub ahead of print.