PREDICTING THE PATIENT AT LOW-RISK FOR LYMPH-NODE METASTASIS WITH LOCALIZED PROSTATE-CANCER - AN ANALYSIS OF 4 STATISTICAL-MODELS

Purpose: Statistical models using preoperative Prostate-Specific Antig en, Gleason primary grade or score of the biopsy specimen, and clinica l stage have been developed to predict those patients with clinically localized prostate cancer at low risk for lymph node metastasis. It ha s been recommended that these patients do not require pelvic lymph nod e dissections. Four such models were evaluated to assess their accurac y in identifying this subgroup of patients. Methods and Materials: We reviewed the records of 214 patients with clinically localized prostat e cancer who underwent pelvic lymph node dissections. Data from these patients were entered into the four models. Results: Lymph node metast asis was detected in 14% of patients. The results showed the following for each of the proposed models respectively: 78, 50, 76, and 42% of the patients were identified as low risk and, hence, would be spared p elvic lymph node dissections. The false negative rates are 13 (7.8%), 5 (4.6%), 14 (8.6%), and 1 (1.1%). Sensitivities are 56.7, 83.3, 53.3, and 96.7%. Conclusions: While the pelvic lymph node dissection is the most accurate method of detecting occult nodal metastasis, statistica l models can identify a cohort of low risk patients that may be spared lymphadenectomy.