The incidence of lymph node metastases in prostate carcinoma depends not only on tumor characteristics but also on surgical performance and extent of pelvic lymphadenectomy

Objectives. The purpose of the present study was to determine whether predictions of the incidence of pelvic lymph node metastases in patients with similar prostate cancer characteristics are influenced by the extent of pelvic lymphadenectomy or surgical performance.
Material and methods. Data from a prostate cancer database were analyzed to investigate associations between incidence of lymph node metastasis and preoperative prostate-specific antigen level, clinical stage, biopsy Gleason score, extent of pelvic lymphadenectomy, and surgical performance. Subgroups of patients with the same characteristics were formed, and a multivariate analysis was performed.
Results. Data of 668 patients with cT1-T2c prostate cancer who underwent radical retropubic prostatectomy with pelvic lymphadenectomy were analyzed. Lymph node metastases were found in 8.7% of these patients. In the subgroup of patients undergoing limited pelvic lymphadenectomy, 6.3% were affected compared with 14.7% of patients undergoing extended pelvic lymphadenectomy (P<0.0005). In the subgroups of patients with the same tumor characteristics (with only two exceptions), the impact of the extent of lymphadenectomy on the incidence of lymph node metastases was evident. The results of the multivariate analysis corroborated the influence of the extent of pelvic lymphadenectomy (P<0.03) and surgical performance (P<0.04) on the incidence of lymph node metastases.
Conclusions. The incidence of lymph node metastases was dependent not only on preoperative prostate-specific antigen level, clinical stage, and biopsy Gleason score but also to a large degree on surgical performance and the extent of pelvic lymphadenectomy. Our data suggest that a limited and/or not thoroughly performed pelvic lymphadenectomy results in failure to detect a relevant proportion of lymph node metastases.