Predictor Factors for the Detection of Positive Nodes in Patients Undergoing Radical Prostatectomy and Lymph Node Dissection

Background: The detection of positive lymph nodes after a lymph node dissection changes the clinical prognosis; therefore, we evaluated what factors help us predict the presence of positive lymph nodes. Methods: A retrospective analysis of all radical prostatectomies and extended lymph node dissection performed from January 2010 to October 2018 in our centre was conducted. The variables included in the Briganti nomogram (preoperative PSA, Gleason biopsy, percentage of cores, and clinical stage) were considered, as well as perineural invasion and involvement of the seminal vesicles in the prostate biopsy; Results: A total of 110 lymph node dissections are obtained. Patient mean age is 64.18 years (46.55–75.91). Of the 110 lymphadenectomies performed, 16 patients (14.5%) presented positive nodes. Presenting infiltrated seminal vesicles, perineural invasion, higher PSA, higher clinical stage, higher Gleason biopsy and percentage of cores is more likely to have statistically significant lymph node involvement (p < 0.05). In the multivariate analysis, the percentage of positive core, together with the involvement of the seminal vesicles and Gleason ≥ 4 in the majority are predictor factors for positive nodes (p < 0.01); Conclusions: The percentage of positive cores, the involvement of the seminal vesicles, and the majority Gleason ≥ 4 are independent predictors of lymph node involvement in prostate cancer.