ANATOMICAL BASIS FOR PELVIC LYMPHADENECTOMY IN PROSTATE-CANCER - RESULTS OF AN AUTOPSY STUDY AND IMPLICATIONS FOR THE CLINIC

Purpose: Pelvic lymphadenectomy remains the most reliable method to pr ove lymph node metastases in prostate cancer. However, evaluation of l ymphadenectomy to be complete and sufficient as judged by the number o f removed lymph nodes is hampered by the fact that, in contrast to oth er malignancies (for example breast or gastric cancer), anatomical stu dies investigating the regular and average number of pelvic lymph node s are missing. We established an anatomically based standard for pelvi c lymphadenectomy. Materials and Methods: Standard pelvic lymphadenect omy was performed on 30 human cadavers and 59 consecutive patients wit h clinically organ confined prostate cancer during radical retropubic prostatectomy. Number, size and topography of the lymph nodes were not ed separately for each anatomical region of both iliac fossas. Results : The mean number of lymph nodes removed in the autopsy series plus or minus standard deviation (22.7 +/- 10.2, range 8 to 56) was nearly id entical to that from patients with prostate cancer (20.5 +/- 6.6, rang e 10 to 37) but striking interindividual differences were observed. Pa tients with prostate cancer demonstrated enlarged nodes regardless of whether they did or did not contain tumor. Interestingly, pelvic lymph node metastases were more common on the left side regardless of the p rimary tumor site. Conclusions: Approximately 20 pelvic lymph nodes ma y serve as a guideline for a sufficient standard pelvic lymph node dis section. Lymphadenopathy in prostate cancer patients is not always a r esult of metastases but, rather, hyperplastic or regressive alteration s. A preferential distribution of lymph node metastases along the left iliac vessels regardless of the primary tumor site in the prostate wa rrants further investigation.