A useful method for assessing differences of compensatory hypertrophy in the contralateral kidney before and after radical nephrectomy in patients with renal cell carcinoma: ellipsoid formula on computed tomography

Correlation between bilateral GFR in patients with localized renal cancer after partial nephrectomy

OBJECTIVE

To explore the relationship between the residual glomerular filtration rate (GFR) on the operated side and the GFR on the contralateral side following partial nephrectomy (PN) in patients with localized renal cell carcinoma (RCC).

MATERIALS AND METHODS

Following institutional review board approval, we conducted a retrospective analysis of clinical records from May 2018 to July 2023, involving 118 patients who underwent partial nephrectomy for unilateral localized kidney tumors (T1-T2). Glomerular filtration rate data were assessed using single photon emission computed tomography (SPECT)/computed tomography imaging [using 9mTc-DTPA (diethylenetriaminepentaacetic acid) renal dynamic imaging]. The independent determinants of postoperative renal function or renal function change were determined using linear regression analysis. In addition, the patient's demographic, clinical, and nephrometry characteristics were collected.

RESULTS

A total of 58 patients were finally enrolled. The preoperative and postoperative GFR of bilateral kidneys showed a significant positive correlation. Postoperative GFR of the operated kidney was the independent predictor of GFR of contralateral kidney (p = 0.001). Tumor diameter (p = 0.036), age (p = 0.005), and postoperative GFR of the contralateral kidney (p = 0.001) were all independent predictors of postoperative GFR of the operated kidney. ΔGFR1 was the independent predictor of ΔGFR2. Results showed that a more pronounced postoperative decline in GFR on the operated side corresponded to a weaker compensatory capacity of the contralateral-side kidney.

CONCLUSIONS

During the course of the surgical procedure, the active endeavor to safeguard the renal function of the operated kidney side holds paramount importance, which yields positive outcomes for postoperative kidney function on the contralateral side, consequently contributing to the overall preservation of renal function.

Virtual Resection: A New Tool for Preparing for Nephron-Sparing Surgery in Wilms Tumor Patients

Nephron-sparing surgery (NSS) in Wilms tumor (WT) patients is a surgically challenging procedure used in highly selective cases only. Virtual resections can be used for preoperative planning of NSS to estimate the remnant renal volume (RRV) and to virtually mimic radical tumor resection. In this single-center evaluation study, virtual resection for NSS planning and the user experience were evaluated. Virtual resection was performed in nine WT patient cases by two pediatric surgeons and one pediatric urologist. Pre- and postoperative MRI scans were used for 3D visualization. The virtual RRV was acquired after performing virtual resection and a questionnaire was used to assess the ease of use. The actual RRV was derived from the postoperative 3D visualization and compared with the derived virtual RRV. Virtual resection resulted in virtual RRVs that matched nearly perfectly with the actual RRVs. According to the questionnaire, virtual resection appeared to be straightforward and was not considered to be difficult. This study demonstrated the potential of virtual resection as a new planning tool to estimate the RRV after NSS in WT patients. Future research should further evaluate the clinical relevance of virtual resection by relating it to surgical outcome.