Age-Stratified Outcomes of Off-Clamp Robot-Assisted Partial Nephrectomy: A Comparison of Patients Younger Than 65 Years and Those Aged 65 Years or Older

Background: Evidence for completely off-clamp robot-assisted partial nephrectomy (RAPN) in older patients is limited. We compared age-stratified short-term outcomes. Methods: We reviewed 146 consecutive patients who underwent off-clamp RAPN between June 2022 and March 2026: 99 were aged <65 years and 47 were aged ≥65 years. Outcomes included perioperative measures, 90-day major complications, postoperative day 1 (POD1) hemoglobin (Hb) decline, estimated glomerular filtration rate (eGFR) change, and surgical margin status. Parsimonious linear models adjusted for age group, baseline Hb or eGFR, tumor size, and RENAL score; expanded models were sensitivity analyses. Results: Older patients had more hypertension, diabetes mellitus, and cardiovascular disease and lower baseline Hb and eGFR (all P < .05). Console time, estimated blood loss, and length of stay did not differ significantly, and no major complication occurred. Positive margins occurred in 5/85 younger and 1/44 older patients with evaluable data ( P = .663); margin status was unassigned in 17 nonmalignant cases. The median POD1 Hb decline was 1.0 versus 1.2 g/dL ( P = .779), and the median 1-month eGFR change was 1.0 mL/min/1.73 m 2 in both groups ( P = .746). In parsimonious models, neither age-group coefficient reached statistical significance: Hb decline, β = −0.01 (95% confidence interval [CI], −0.30 to 0.28; P = .937); 1-month eGFR change, β = −3.21 (95% CI, −6.80 to 0.38; P = .080). Conclusions: No statistically significant age-group differences were detected in the evaluated short-term perioperative and functional outcomes. However, the confidence intervals, particularly for 1-month eGFR, did not exclude clinically relevant disadvantage in older patients and do not establish equivalence.