Optimization of Extended Pelvic Lymph Node Dissection Side for Prostate Cancer.

BACKGROUND

This study aimed to show the association between tumor location and laterality of positive lymph nodes by evaluating biopsy and magnetic resonance imaging (MRI) findings, and to optimize the extended pelvic lymph node dissection (ePLND) side for prostate cancer.

METHODS

The study enrolled patients who underwent robot-assisted radical prostatectomy with ePLND. Tumor locations were determined according to International Society of Urological Pathology grade group 4/5 in biopsies and Prostate Imaging-Reporting and Data System category 4/5 in MRI results. The concordance of tumor location lobe and positive lymph node side with the performance of tumor location-guided ePLND for positive lymph node detection was evaluated.

RESULTS

For 301 patients who underwent ePLND at Kyushu University Hospital, tumor locations determined by biopsy and MRI findings showed no lesion in 8 (2.7%) patients, unilateral lobe in 223 (74.1%) patients, and bilateral lobe in 70 (23.3%) patients. The accuracies for detection of any and all positive lymph nodes by tumor location-guided unilateral ePLND were 99.6% and 97.3%, respectively. Among the patients at St. Luke's International Hospital, the accuracies for detection of any and all positive lymph nodes by tumor location-guided unilateral ePLND were estimated to be 99.0% and 97.3%, respectively.

CONCLUSIONS

This study proposed tumor location-guided ePLND according to biopsy and MRI findings. This novel strategy is expected to reduce the burden of bilateral ePLND at the cost of acceptable risk of failing to detect positive lymph nodes.