Background/Objectives: Adherent perinephric fat (APN) is common in laparoscopic partial nephrectomy (LPN). It is absent from the lists of recognised positive surgical margin (PSM) predictors. We tested whether APN is associated with PSM risk and whether the effect varies by resection technique. Methods: We analysed 401 International Society of Urological Pathology (ISUP)-gradable renal cell carcinomas (31 PSM events; chromophobe RCC was excluded from the primary cohort because the WHO/ISUP grade is not assignable) carried out at three centres by eight surgeons from 2013 to 2024. Nested logistic models added APN, then an APN × enucleation interaction, to a guideline-based covariate set (tumour size, ISUP grade ≥ 3, cT1b stage, centre fixed effects, surgeon-documented enucleation). Firth penalisation and a 2000-replicate bootstrap were used to limit small-sample bias; they cannot add information beyond the 31 observed events. Results: APN was an independent PSM predictor (adjusted odds ratio [OR] 2.68, 95% confidence interval [CI] 1.21 to 5.95, p = 0.02). The effect was technique-conditional: APN × enucleation interaction OR 7.83 (95% CI 1.08 to 56.92, p = 0.04), consistent in direction across estimators but imprecise in magnitude. PSM occurred in 29.4% of APN-positive enucleation cases (odds ratio 10.21, 95% CI 2.07 to 50.30; Fisher exact p = 0.003), against 5.0% in enucleoresection and 10.8% in resection. Conclusions: In this cohort the APN-to-PSM association was technique-conditional. The penalty concentrates in enucleation; the rim-retaining strata gave estimates compatible with both no association and clinically important harm (OR 0.99 and 1.96, both intervals wide). Because the interaction rests on few margin events and the technique was not randomised, this finding is hypothesis-generating: when APN is encountered intraoperatively, retaining a parenchymal rim (enucleoresection or resection) rather than enucleation may be considered, pending prospective validation.

Objective: Positive surgical margins remain clinically relevant after robot-assisted radical prostatectomy (RARP). Whether performing extended pelvic lymph node dissection (ePLND) before, rather than after, prostatectomy is associated with lower apical positive surgical margin (PSM) rates has not been evaluated with adjusted comparative data.Materials and Methods: We performed a retrospective cohort study of 250 consecutive patients who underwent primary RARP with ePLND at a single tertiary centre. Patients were classified by operative sequence as ePLND-first (n = 121) or prostatectomy-first (n = 129). The primary multivariable analyses were conducted in the full 250-patient cohort with nerve-sparing intent coded as a 3-level categorical variable; a pre-specified subgroup analysis was conducted in the 188 patients undergoing any form of nerve-sparing surgery. The primary endpoint was apical PSM. Because apical PSM events were sparse, the adjusted analysis used Firth penalised logistic regression.Results: Baseline characteristics were similar between groups. Apical PSM occurred in 6 of 121 patients (5.0%; 95% confidence interval [CI] 2.3% to 10.4%) in the ePLND-first group and 13 of 129 (10.1%; 95% CI 6.0% to 16.5%) in the prostatectomy-first group. In the primary multivariable analysis of the full 250-patient cohort, ePLND-first sequencing was associated with lower adjusted odds of apical PSM (adjusted OR 0.38; 95% CI 0.14 to 1.03; p = 0.056); in the pre-specified nerve-sparing subgroup (n = 188), the adjusted association was stronger (OR 0.19; 95% CI 0.04 to 0.97; p = 0.046; unadjusted 1.2% vs 8.8%, Fisher’s exact p = 0.023). Total operative time was shorter in the ePLND-first group (195.2 vs 202.9 min; p = 0.029). Lymph node yield and major complication rates were similar between groups.Conclusion: In this retrospective cohort, performing ePLND before prostatectomy was associated with directionally lower adjusted odds of apical PSM during RARP in the full 250-patient cohort, with a stronger association in the pre-specified nerve-sparing subgroup analysis. For men undergoing nerve-sparing RARP with planned ePLND, sequence may represent a practical operative strategy associated with lower apical margin risk without an evident perioperative penalty.