The asociation between the number of nodes removed at retroperitoneal lymph node dissection and overall- and cancer-specific survival in patients with nonseminomatous germ cell tumor.

Abstract

4572 Background: The benefit of a thorough retroperitoneal lymph node dissection (RPLND) for testicular cancer has been well established and essentially eliminates retroperitoneal recurrence of disease. RPLND is known to be a complex, advanced procedure and the number of nodes removed may vary amongst institutions. Thus, we explored whether number of nodes removed at RPLND may predict overall- and cancer-specific survival in patients with non-seminomatous germ cell tumor (NSGCT) who have undergone RPLND. Methods: We retrospectively searched the Surveillance Epidemiology and End Results (SEER) database for all patients who had undergone RPLND for NSGCT between 1973 and 2006. We performed logistic regression to assess the ability of number of nodes removed at RPLND to predict overall and cancer specific survival. We adjusted for age, stage, and lymph node density. In addition, we used Kaplan-Meier life table analysis to evaluate actuarial survival probability as a function of removed nodes at the time of RPLND. Results: The cohort consisted of 1262 patients. The median age and median number of nodes removed at RPLND were 29 years (0-71) and 16 (+/- 13.5 SD), respectively. Of all patients, 48.5%, 45.9%, and 5.3% were stage I, II and III, respectively. On multivariate analysis, stage (<0.001), age (HR 1.056; p<0.001), and number of nodes removed (p=0.015) were all significant predictors of overall mortality. On Kaplan-Meier analysis, mean time to overall mortality (16.9 vs. 18.4 years, p<0.001) and cancer specific mortality (17.7 vs. 18.8 years, p<0.001) were significantly shorter for patients that had 5 or fewer nodes removed compared to those than had 6 or more removed. Conclusions: The number of nodes removed at RPLND significantly predicted the overall- and cancer-specific survival in patients with NSGCT. Moreover, patients with fewer nodes removed at time of RPLND had significantly shorter mean actuarial overall survival and cancer specific survival. This analysis emphasizes the critical importance of a thorough RLPND on survival in patients with testicular cancer.