Re-evaluation of the need for pelvic lymphadenectomy in low grade prostate cancer

In a series of 166 patients undergoing radical prostatectomy and bilateral pelvic lymph node dissection for clinical stage A and B prostate cancer we found that 83% of patients with lymph node metastases had a final tumour Gleason score > or = 7. Gleason scoring of the pre-operative biopsy demonstrated 3 groups of patients with biopsy scores < or = 5, 6, and > or = 7, and a prevalence of lymph node metastases of 2, 13 and 23% respectively. The pre-operative serum prostate specific antigen (PSA) was of marginal value in predicting either the presence of lymph node metastases or the presence of cancer, since 15% of patients with nodal metastases had normal pre-operative PSA levels, as did 54% of patients with tumour Gleason scores < or = 5. It was concluded that the need for pelvic lymph node dissection in patients with low grade tumours is questionable because of the low prevalence of lymph node metastases, and that the pre-operative biopsy can identify those patients who are at low risk for lymph node metastases.