Selective lymph node dissection for castration-resistant prostate cancer.

Background: No relevant data have been published on the impact of retroperitoneal lymph node dissection (LND) on clinical outcome in patients with castration-resistant prostate cancer.

Methods: We retrospectively studied the records of 6 patients with lymph node metastases from castration-resistant prostate cancer who underwent a retroperitoneal LND between 2005 and 2010. Complication rate and clinical outcome were examined.

Results: Mean patient age was 69.2 (63-81) years. Primary therapy was radical prostatectomy, radiation therapy, or pelvic LND and androgen deprivation in 3, 2 and 1 cases, respectively. Mean prostate-specific antigen (PSA) at LND was 37.6 (20.3-139) ng/dl. LND was performed as a modified unilateral (n = 3), bilateral (n = 1) and bilateral extended (n = 2) approach with a median lymph node density of 0.739 (0.111-1). Preoperative Charlson index was 0 (n = 3) or 1 (n = 3). No intra- or postoperative complications occurred. The average postoperative decline of PSA was 39.3% (-99.4 to +31.3). Differences between mean pre- and postoperative PSA velocities and densities were 23.9 ng/ml/year and 11.2 months, respectively (p = 0.24 and p = 0.40). Four patients (67%) developed bone metastases after a mean period of 23.5 (5-58) months. Median bone metastases-free survival was 15.5 months and median overall survival after LND was 31.7 months on Kaplan-Meier analysis.

Conclusions: A selective LND in castration-resistant prostate cancer patients could be safely performed. A positive effect on the PSA and PSA kinetics was accomplished for the majority of patients. This new surgical approach represents an alternative treatment option in the palliative setting of prostate cancer patients and could delay toxic systemic therapy up to 12 months.