Differential contribution of the factors determining long-term renal function after partial nephrectomy over time

Area of Science:

• Nephrology
• Urology
• Surgical Outcomes

Background:

• Partial nephrectomy (PN) is a standard treatment for renal tumors.
• Assessing long-term renal function after PN is crucial for patient management.
• Understanding the determinants of renal function recovery post-PN is essential.

Purpose of the Study:

• To determine the long-term impact of preserved renal parenchymal volume and ischemic insult on renal function after partial nephrectomy (PN).
• To evaluate the time-varying contribution of perioperative variables to ipsilateral glomerular filtration rate (GFR) following PN.

Main Methods:

• Analysis of data from 530 patients who underwent PN.
• Renal function (GFR) measured preoperatively, at 3 months, and annually using 99mTc-diethylenetriaminepentaacetic acid renal scan.
• Linear mixed-effects model used to assess time-varying contributions of perioperative variables to long-term ipsilateral GFR.

Main Results:

• Ipsilateral GFR decreased by 27.3% at 3 months post-PN but recovered significantly over 5 years.
• Parenchymal volume reduction and ischemic time were consistently associated with postoperative GFR.
• Diabetes and proteinuria, initially insignificant, became significant determinants of GFR at 5 years.

Conclusions:

• Renal function recovery after PN continues for up to 5 years.
• Parenchymal volume loss is the primary long-term determinant of renal function, with a constant impact.
• Ischemic time's effect on GFR diminishes over time, while patient-related factors like diabetes and proteinuria gain significance.