Gill, Inderbir S.

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.

Objectives: To report the outcomes of minimally invasive (MIS) nephrectomy following immune checkpoint inhibitor (ICI) therapy. Materials and Methods: This multicenter retrospective cohort study included consecutive patients who underwent nephrectomy following ICI therapy at five high-volume US academic centers between 2015 and 2023. Baseline clinical features and perioperative findings were recorded. After propensity-score matching (PSM), outcomes were compared between MIS and open nephrectomies. The primary outcome was 90-day complications, and secondary outcomes included length of hospital stay (LOS) and 90-day readmission. Results: A total of 158 patients were included, of whom 76 and 82 underwent MIS and open nephrectomies, respectively. The MIS procedures included robotic ( n = 56) and laparoscopic ( n = 20). A total of six (8%) patients converted to open. On multivariable analysis, patients with nonmetastatic vs metastatic renal-cell carcinoma (RCC) (hazard ratio [HR] 3.1, p = 0.01), those with smaller tumor size (HR 1.2 for each cm, p = 0.001), and no clinical evidence of inferior vena cava thrombus (HR 29, p = 0.002) were more likely to undergo the MIS approach compared with open approach. After PSM, including 56 MIS and 36 open nephrectomies, the MIS group compared with the open group had lower estimated blood loss (100 vs 460 mL, p < 0.001) and shorter LOS (2 vs 4 days, p < 0.001). Nevertheless, 90-day complications and readmissions were similar between the two groups. There were no 90-day mortality rates in either group. Conclusion: The MIS approach appears safe and offers more favorable perioperative outcomes compared with open surgery in properly selected patients with advanced RCC who are candidates for nephrectomy following ICI therapy.

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.

AbstractObjectiveTo evaluate the relationship between pre‐operative PSA value, 68Ga‐prostate‐specific‐membrane‐antigen (PSMA) PET performance and oncologic outcomes after salvage lymph node dissection (sLND) for biochemical recurrent prostate cancer (PCa).Patients and methodsThe study included 164 patients diagnosed with ≤2 pelvic lymph‐node recurrence(s) of PCa documented on 68Ga‐PSMA PET scan and treated with pelvic ± retroperitoneal sLND at 11 high‐volume centres between 2012 and 2019. Pathologic findings were correlated to PSA values at time of sLND, categorized in early (<0.5 ng/ml), low (0.5–0.99 ng/ml), moderate (1–1.5 ng/ml) and high (>1.5 ng/ml). Clinical recurrence (CR)‐free survival after sLND was calculated using multivariable analyses and plotted over pre‐operative PSA value.ResultsMedian [interquartile range (IQR)] PSA at sLND was 1.1 (0.6, 2.0) ng/ml, and 131 (80%) patients had one positive spot at PET scan. All patients received pelvic sLND, whereas 91 (55%) men received also retroperitoneal dissection. Median (IQR) number of node removed was 15 (6, 28). The rate of positive pathology increased as a function of pre‐operative PSA value, with highest rates for patients with pre‐operative PSA > 1.5 ng/ml (pelvic‐only sLNDs: 84%; pelvic + retroperitoneal sLNDs: 90%). After sLND, PSA ≤ 0.3 ng/ml was detected in 67 (41%) men. On multivariable analyses, pre‐operative PSA was associated with PSA response (p < 0.0001). There were 51 CRs after sLND. After adjusting for confounders, we found a significant, non‐linear relationship between PSA level at sLND and the 12‐month CR‐free survival (p < 0.0001), with the highest probability of freedom from CR for patients who received sLND at PSA level ≥1 ng/ml.ConclusionsIn case of PET‐detected nodal recurrences amenable to sLND, salvage surgery was associated with the highest short‐term oncologic outcomes when performed in men with PSA ≥ 1 ng/ml. Awaiting confirmatory data from prospective trials, these findings may help physicians to optimize the timing for 68Ga‐PSMA PET in biochemical recurrent PCa.

29 Background: Better biomarkers are needed in prostate cancer (PCa) to predict disease recurrence and guide optimal therapy. We investigated whether genes associated with a highly tumorigenic, drug resistant, progenitor cancer phenotype impact PCa biology and clinical outcomes in localized disease. Methods: Genes associated with self-renewal, drug resistance, and tumorigenicity were analyzed by qRT-PCR on PCa mRNA from radical prostatectomy (RP) specimens (+/- disease recurrence). Wilcoxon rank sum two-sample test, multivariable recursive partitioning, and bootstrap internal validation measured and confirmed associations with recurrence. Further validation was conducted in external cohorts and in-silico, as well as in vitro and in vivo using siRNA knockdown and lentiviral overexpression to determined the effect of gene expression on PCa proliferation, invasion and tumor growth. Results: Four candidate genes were differentially expressed in PCa recurrence, and of these, low AXIN2 expression was internally validated. Validation in external cohorts demonstrated low AXIN2 expression was associated with more aggressive prostate cancer and was independently associated with biochemical recurrence (BCR) and metastasis-free survival (MFS) after RP. In vitro, low AXIN2 expression was associated with a cancer stem-like cell-surface signature, and siRNA knockdown of AXIN2 resulted in significantly greater invasiveness. Conversely, ectopic overexpression of AXIN2 significantly reduced cell proliferation and tumor growth in mice. Conclusions: Low AXIN2 expression was associated with PCa recurrence after RP in our test population as well as in external validation cohorts. AXIN2 expression levels in PCa cells significantly impacted invasiveness, proliferation and tumor growth. AXIN2 represents a putative biomarker and potential therapeutic target in early prostate cancer.