Munich, Germany (UroToday.com) In today’s prostate cancer poster session at the 2016 EAU annual meeting, Dr. Maderthaner and colleagues presented their work on comparative effectiveness of two different templates for pelvic lymph node dissection at the time of radical prostatectomy.
Utilizing mapping studies, the investigators previously reported that standard lymph node dissections may not adequately address regions that are at risk for spread of disease, including along the common iliac vessels, medial to the internal iliacs, and the presciatic space.
Their current study included 714 prostatectomy patients who were treated from 2000-2015. This was divided into a historical template cohort of 2000-2008 (n=465) and contemporary cohort of 2008-2015 (n=249).
The authors removed more lymph nodes in the contemporary cohort relative to the historical cohort (34 vs. 25 nodes, p<0.0001). Node count was significantly higher in the contemporary cohort for the external iliac (16 vs. 19) and internal iliac regions (6 vs. 8, both significant), but not for the common iliacs (3 vs. 4). A median of 5 lymph nodes was removed from the presciatic space in the contemporary group.
The expanded nodal yield had an impact on positive nodes identified. The historical cohort had a positive node rate of 17%, while 28% were positive in the contemporary group. While the historical cohort had a greater proportion of patients with positive nodes in the external iliacs and similar proportion of positive nodes in the internal iliacs, the contemporary cohort had 4 times higher proportion of patients with positive nodes in the common iliacs. Moreover, 7% of the contemporary group had positive nodes in the presciatic space. Multivariable analysis controlling for age, stage, Gleason, and PSA, the contemporary group was 23% more likely to harbor nodal mets relative to the historical group.
The authors concluded that an extended PLND that covers the common iliacs, medial to the internal iliacs, and presciatic space has the ability to detect a higher proportion of patients with positive nodal disease.
Reported By:
Nikhil Waingankar, MD, at the 31st Annual EAU Congress - March 12 - 15, 2016 – Munich, Germany
Fox Chase Cancer Center