Objectives: To characterize lymph node metastasis of prostate cancer (PCa) and identify the parameters associated with patient outcome. The incidence of clinically localized PCa with concurrent lymph node metastasis has decreased to less than 1% in the United States but is between 10% and 15% in other countries.
Methods: Our study cohort of 1148 patients underwent radical prostatectomy in Ulm, Germany, between 1986 and 2002, and 201 (18%) had lymph node-positive PCa.
Results: The metastases showed growth architecture resembling primary PCa. We assigned a Gleason pattern and evaluated for size, extranodal extension, and lymphovascular invasion (LVI). Of 201 patients, 155 had original pathology slides available; 36 of the 155 were excluded because of preoperative hormonal ablation therapy. Of the remaining 119 patients, 22 (19%) were assigned Gleason pattern 3, 93 (78%) Gleason pattern 4, and 4 (3%) Gleason pattern 5. Extranodal extension was present in 66 (55%) of 119 patients and LVI in 29 (25%). An increased risk of prostate-specific antigen (PSA) recurrence was found for Gleason pattern 4/5 (hazard ratio [HR] 2.5, P = 0.038), LVI in the lymph nodes (HR 1.9, P = 0.038), and nuclear grade of the primary tumor (HR 2, P = 0.025). Independent predictors of PSA recurrence included LVI and nuclear grade (HR 1.9, P = 0.03 and HR 2, P = 0.03, respectively).
Conclusions: Lymph node metastases of PCa are heterogeneous and have a close relation to the corresponding primary tumor. Most patients with lymph node-positive PCa remained disease free for up to 13 years after radical prostatectomy. Independent predictors of PSA recurrence among those with lymph node-positive PCa included LVI in the lymph nodes and the nuclear grade of the primary tumor. These parameters may be useful in predicting PSA recurrence in lymph node-positive PCa and could be included in patient follow-up.