Marra, Giancarlo

Objectives To evaluate biochemical recurrence‐free survival (BRFS) and metastasis‐free survival (MFS) as potential intermediate clinical endpoints (ICEs) for overall survival (OS) in patients undergoing salvage radical prostatectomy (sRP). Patients and Methods Evaluable patients were selected from a retrospective dataset, resulting in a cohort of 879 patients with recurrent, non‐metastatic, hormone‐sensitive prostate cancer treated with sRP at 13 centres. ICE surrogacy was evaluated using a two‐stage approach: (i) at the individual‐patient level by fitting Clayton copula models and estimating Kendall's ( >0.7 indicating a strong association) and (ii) at the centre level, by fitting weighted linear regression of 5‐year OS on 3‐year BRFS and MFS. Results The two‐step analysis included 759 patients for BRFS (366 events) and 476 for MFS (137 events), with median follow‐up of 37 months (95% confidence interval [CI] 36–42 months) and 34 months (95% CI 31–37 months), respectively. At the individual‐patient level, MFS showed a strong association with OS (Kendall's 0.85, 95% CI 0.82–0.88), which was not observed for BRFS (Kendall's 0.63, 95% CI 0.56–0.69). At the centre level, neither 3‐year BRFS ( R 2 = 0.15; slope = 0.34, P = 0.2) nor 3‐year MFS ( R 2 = 0.21; slope = 0.26, P = 0.14) predicted 5‐year OS with sufficient explanatory power. Limitations include the fact that centre‐level analysis was based on single‐arm associations rather than on treatment‐effect surrogacy across arms, and retrospective data collection. Conclusions The BRFS should not be used as a surrogate endpoint in the sRP setting. MFS requires further validation in future prospective studies to confirm its association with OS. Patient‐reported outcomes, such as quality‐of‐life and treatment‐related toxicity, should be considered in parallel with OS.

Background: Lymph node invasion (LNI) represents a poor prognostic factor after primary radical prostatectomy (RP) for prostate cancer (PCa). However, the impact of LNI on oncologic outcomes in salvage radical prostatectomy (SRP) patients is unknown. Objective: To investigate the impact of lymph node dissection (LND) and pathological lymph node status (pNX vs. pN0 vs. pN1) on long-term oncologic outcomes of SRP patients. Patients and methods: Patients who underwent SRP for recurrent PCa between 2000 and 2021 were identified from 12 high-volume centers. Kaplan–Meier analyses and multivariable Cox regression models were used. Endpoints were biochemical recurrence (BCR), overall survival (OS), and cancer-specific survival (CSS). Results: Of 853 SRP patients, 87% (n = 727) underwent LND, and 21% (n = 151) harbored LNI. The median follow-up was 27 months. The mean number of removed lymph nodes was 13 in the LND cohort. At 72 months after SRP, BCR-free survival was 54% vs. 47% vs. 7.2% for patients with pNX vs. pN0 vs. pN1 (p < 0.001), respectively. At 120 months after SRP, OS rates were 89% vs. 81% vs. 41% (p < 0.001), and CSS rates were 94% vs. 96% vs. 82% (p = 0.02) for patients with pNX vs. pN0 vs. pN1, respectively. In multivariable Cox regression analyses, pN1 status was independently associated with BCR (HR: 1.77, p < 0.001) and death (HR: 2.89, p < 0.001). Conclusions: In SRP patients, LNI represents an independent poor prognostic factor. However, the oncologic benefit of LND in SRP remains debatable. These findings underline the need for a cautious LND indication in SRP patients as well as strict postoperative monitoring of SRP patients with LNI.