Abstract: PD24-03
Sources of Funding: none

Introduction

The role of salvage lymphnode dissection (sLND) in patients (pts) with PET positive PCa relapse to delay the administration of systemic therapy is still under debate. The aim of our study was to describe the oncological outcomes of pts undergoing sLND after positive PET signals for suspicious nodal recurrence.

Methods

Between 2009 and 2016, 43 consecutive patients with nodal uptake at PET/CT scan (Cholin, Acetate, PSMA, Bombesin) suggesting presence of nodal recurrence after curative treatment underwent 49 sLNDs at a single institution. After surgery, PSA values were measured systematically. When post-sLND PSA nadir was <0.01 ng/ml, salvage treatment failure (sTF) was defined by biochemical recurrence (BCR, PSA >0.2 ng/ml, Group A). When post-sLND PSA Nadir was >0.01 ng/ml, sTF was recorded when post-sLND PSA value reached the pre-sLND value (Group B) or when an additional salvage PCa treatment was given (Group C). Student't T test was used to compare means.

Results

Overall, 42 and 1 out of 43 patients underwent radical prostatectomy and brachytherapy, respectively. Mean and median PSA value at PET/CT scan were 6.7 and 2.9 ng/ml (IQR 1.2-6.1), respectively. Open and laparoscopic sLNDs were performed in 37/49 (76%) and 12/49 (34%), respectively. Histological report was positive for PCa in 36/49 sLND (73%). Five of 36 patients were lost at follow up. Group A consisted of 4 patients and 2 had sTF. Group B and C consisted of 14 and 13 patients and all had sTF. Mean and median PSA value before sLND in Group A, B, C were 1.4 and 1.3 ng/ml (IQR 0.6-2.2), 9 and 3.5 ng/ml (IQR 1.6-12.9), 9.4 and and 3.5 ng/ml (IQR 2.3-16.9), respectively. Median PSA nadir in group B and C was 0.67 ng/ml (IQR 0.36-2.6) and 3.14 ng/ml (IQR 0.7-4.4), respectively (p=0.3). Median time to sTF was 11 months (IQR 8-55 months), 5 months (IQR 1.7-13.2) and 4 months (IQR 2.0-10) for group A, B and C. Mean time to sTF in Group A was significantly superior to mean time in Group B and C together (p=0.01). Only 2 of 43 patients were long-term free of recurrence. Limitations of this study are missing PET controls after sLND and PSA persistence, low patient numbers and the retrospective design.

Conclusions

Only pts with positive histological report with a PSA nadir <0.01 ng/ml after sLND seem to have a long-term benefit. Pts with a PSA nadir >0.01ng/ml have a delay of systemic treatment of up to 5 months. Pts without PSA response do not benefit from sLND.

Funding

none