Mid-term Outcomes Following Salvage Lymph Node Dissection for Prostate Cancer Nodal Recurrence Status Post–radical Prostatectomy

Background: Patients with oligometastatic prostate cancer lymph node recurrence can be treated with many options including salvage lymph node dissection (sLND). Objective: EvaluationofoutcomesofsLNDandidentificationofclinicopathologicfeatures in predicting further biochemical and radiological relapse after sLND for prostate cancer. Design, setting, and participants: Between November 1, 2009 and March 31, 2015, 117 patients with biochemical recurrence (BCR) after radical prostatectomy (RP) un- derwent sLND by a single surgeon after a standardized 11C-choline positron emission tomography/computed tomography. Outcomemeasurementsandstatisticalanalysis: Biochemicalresponse(BR)wasdefined as a prostate-specific antigen (PSA) < 0.2ng/ml after sLND, BCR was defined as a PSA greater than 0.2 ng/ml with an increased trend after sLND, and radiological recurrence (RAR) was defined as a positive 11C-choline positron emission tomography/computed tomography imaging study or biopsy proven metastasis after sLND. Kaplan-Meier method was used to assess time to BCR, RAR, and cancer-specific mortality. Preoperative and postoperative predictors of BCR and RAR were assessed with Cox regression analyses. Results and limitations: All patients had confirmed lymph node metastasis on final sLND pathology. Median follow-up after sLND was 20.2 mo (interquartile range: 11.8– 33.6). All but one patient had a decrease in PSA while 93/117 (79.5%) patients achieved BR after sLND. In those who achieved BR, a subsequent BCR occurred in 40% of cases (n = 37/93). The 5-yr BCR, RAR, and cancer-specific mortality-free survival rates were 31%, 51%, and 97% respectively. At multivariate analyses, predictors of both BCR and RAR were pathological stage of the tumor at original RP and whether the nodes were castrate resistant prostate cancer. Given the nonrandomized nature, it is not known how these men would have fared according to survival or quality of life by observation, and/or other systemic therapy. Conclusions: An optimal candidate for sLND tends to have pT2 at the original RP and a castration sensitive disease state. sLND could be considered part of a multimodal treatment approach in select patients with castrate-resistant prostate cancer in which delayed/reduced cancer progression could be achieved with a cytoreductive surgery. Patient summary: We found that by performing a salvage lymph node dissection there are many men that can experience a biochemical response and eliminate further 11C- choline positron emission tomography/computed tomography radiographic recurrences.