Presentation Authors: Ulrike Heberling*, Rainer Koch, Angelika Borkowetz, Gustavo B. Baretton, Manfred P. Wirth, Michael Froehner, Dresden, Germany
Introduction: The aim of this study was to investigate predictors of long-term mortality in patients with positive lymph nodes at radical prostatectomy.
Methods: Out of 5997 patients who consecutively underwent radical prostatectomy at our institution in the years 1992-2014, 564 patients with positive lymph nodes and complete data sets were included in this analysis. The mean number of removed lymph nodes was 14.6. The mean follow-up in the surviving patients was 9.9 years. Age (continuous variable), year of surgery (continuous variable), Gleason Score ( < 8 versus 8-10), local tumor stage (extracapsular disease versus organ confined), PSA level ( < 10 ng/ml versus higher or neoadjuvant hormonal therapy), lymph node density (number of involved lymph nodes per number of removed lymph nodes; continuous variable, per 10% increase), lymph node count (continuous variable), and the number of positive lymph nodes (continuous variable) were included in the multivariable competing risk analysis with prostate cancer mortality as endpoint.
Results: After 20 years, 28% of patients (95% confidence interval, CI, 20-36%) died of non-prostate cancer (competing) causes, whereas 29% (95% CI 23-36%) died of prostate cancer. Only lymph node density (per 10% increase, hazard ratio, HR, 1.2, 95% CI 1.0-1.3, p=0.0056) and Gleason score (8-10 versus < 8: HR 6.1, 95% CI 3.3-11.4, p < 0.0001) predicted prostate cancer mortality. Patients with a Gleason score < 8 and a lymph node density /=median was 42% (32-52%), p < 0.0001.
Conclusions: Mortality in patients with positive lymph nodes is determined by tumor biology, neither the year of surgery nor a more extensive lymph node dissection were associated with outcome. Patients with a lymph node density of < 11% and a Gleason score < 8 had an excellent long-term outcome.