Correlation of Prostate Tumor Laterality with Pelvic Lymph Node Metastasis Patterns- A Retrospective Observational Study

INTRODUCTION: Elucidating any spatial concordance between prostate tumor laterality and lymphatic dissemination could inform more individualized treatment planning and contribute to reducing the morbidity associated with current therapeutic strategies, especially lymph node dissection. This study aimed to determine whether the laterality of the dominant intraprostatic lesion correlates with the laterality of pelvic lymph node involvement in patients with node-positive prostate cancer. METHODS: We retrospectively reviewed the medical records of patients who underwent radical prostatectomy with extended pelvic lymph node dissection between April 2013 and September 2024 at three referral centers. Data on patient demographics, prostate-specific antigen levels, pathological findings, and lymph node status were collected and analyzed in accordance with the study objectives. RESULTS: Out of 401 patients, pelvic lymph node involvement was identified in 48 cases (12%). Lymph node involvement is statistically more likely with higher prostate-specific antigen levels and ISUP grade groups compared to those without nodal involvement (P-value: 0.0001). There was a statistically significant correlation between the side of pelvic lymph node involvement (right, left, or bilateral) and the dominant side of prostate cancer (right, left, or bilateral) (P-value: 0.04). CONCLUSION: This study, as expected, identified that higher PSA and ISUP grade group resulted in a higher likelihood of pathologic lymph node involvement. We identified a statistically significant correlation between the dominant side of prostate cancer and the side of pelvic lymph node involvement. This study is preliminary and hypothesis-generating, and its findings require validation in future investigations before they can be considered for clinical application.