[Value of PSA and (pre- postoperative) Gleason in predicting the potential lymphatic involvement in patients with prostatic cancer].

OBJECTIVE: To determine the possibility of selecting patients at risk for lymph node involvement prior to radical prostatectomy utilizing PSA concentration and/or the Gleason score.
METHODS: We reviewed the records of 52 patients with tumor stage T1 to T3, who had undergone lymphadenectomy; of these, 50 patients underwent radical prostatectomy. The predictive values for PSA and the Gleason score and their utility in predicting risk of lymph node involvement were analyzed.
RESULTS: Of the 52 patients, 10 (19%) had lymph node involvement. Nine of 26 patients (35%) with PSA > 20 and 9 of 21 patients (42%) with a Gleason score > 7 had lymph node involvement. No patient with PSA < 15 or Gleason score < 5 and none of the 24 patients (57%) with PSA < 20 and Gleason score < 7 had lymph node involvement. The preoperative biopsy was understaged in 21 patients (41%); of these, 16% had a Gleason score of 5-6. Two of these patients with PSA > 20 micrograms/ml had lymph node involvement.
CONCLUSION: PSA concentration and the Gleason score are useful in predicting the risk of lymph node involvement. Patients with PSA < 20 and a Gleason score of < 7 can be considered to be at no risk and staging lymphadenectomy could be unnecessary. Although the preoperative Gleason score appears to have a predictive value, the possibility of understaging should be taken into account. In this regard PSA can be useful in identifying those patients at risk.