Mid-term oncologic outcomes of radical prostatectomy in lymph node metastatic prostate cancer patients.

OBJECTIVES: Lymph node invasion (LNI) has been reported in 10-15% of pelvic lymph node dissection during radical prostatectomy (RP). The objective of this study was to describe the mid-term oncological outcomes in prostate cancer (PCa) patients with metastatic lymph node. METHODS: We conducted a retrospective study at two French referral centers including consecutive cN0 PCa patients who underwent RP and extended pelvic lymph node dissection and had lymph node metastases on final pathological analysis (pN1) between January 2000 and May 2020. Follow-up was per institution, which generally included a PSA level measurement every 3 to 12 months for 5 years and annually thereafter. RESULTS: A total of 123 patients were included: two (1.6%) low-risk, 64 (52%) intermediate-risk and 57 (46.4%) high-risk PCa according to the D'Amico risk classification. The median number of nodes removed and metastatic nodes per patient was 15 (IQR 11-22) and 1 (IQR 1-2), respectively. Adverse pathological features, i.e., ≥pT3a stage, ISUP grade ≥3, and positive surgical margins were reported in 113 (91.9%), 103 (83.7%), and 73 (59%) of cases, respectively. Postoperative treatment was administered in 104 patients, including radiotherapy alone (n=6), androgen deprivation therapy alone (n=27) or combination with androgen deprivation therapy and radiotherapy (n=71). The mean follow-up was 42.7 months. The estimated 3-year biochemical-free survival, clinical recurrence-free survival, and cancer-specific survival was 66% and 85% and 98.8%, respectively. In Cox regression analysis, the number of metastatic nodes was associated with clinical recurrence (P=0.04) and a persistently elevated PSA with biochemical recurrence (P<0.001). CONCLUSION: The management of lymph node metastatic PCa patients is challenging. Risk stratification of node-positive patients, based on postoperative PSA levels and pathologic features being identified, should help physicians determine which patient would best benefit from multimodal treatment.