Background: Tumor enucleation (TE) optimizes parenchymal preservation and could yield better function than standard partial nephrectomy (SPN), although data on this are conflicting. Objective: To compare functional outcomes for TE and SPN strategies. Design, setting, and participants: Patients managed with partial nephrectomy (PN) with necessary data for analysis of preservation of ipsilateral parenchymal mass (IPM) and global glomerular filtration rate (GFR) from two centers were included. All studies were required <2 mo before and 3–12 mo after surgery. Patients with a solitary kidney or multifocal tumors were excluded. Intervention: Partial nephrectomy. Outcome measurements and statistical analysis: Vascularized IPM was estimated from contrast-enhanced CT scans preoperatively and postoperatively. Serum creatinine-based estimates of global GFR were also obtained in the same timeframes. Univariable and multivariable linear regression evaluated factors associated with new-baseline global GFR. Results/limitations: Analysis included 71 TE and 373 SPN cases. The median preoperative global GFR was comparable for TE and SPN (75 vs 78 ml/min/1.73 m2; p = 0.6). The median tumor size was 3.0 cm for TE and 3.3 cm for SPN (p = 0.03). The median RENAL score was 7 in both cohorts. For TE, warm ischemia and zero ischemia were used in 51% and 49% of cases, respectively. For SPN, warm ischemia and cold ischemia were used in 72% and 28% of patients, respectively. Capsular closure was performed in 46% of TE and 100% of SPN cases (p < 0.001). Positive margins were found in 8.5% of TE and 4.8% of SPN patients (p = 0.2). The median vascularized IPM preserved was 95% (interquartile range [IQR] 91–100%) for TE and 84% (IQR 76–92%) for SPN (p < 0.001). The median global GFR preserved was 101%(IQR 93–111%) and 89% (IQR 81–96%) for TE and SPN, respectively (p < 0.001). On multivariable analysis, resection strategy, preoperative GFR, and vascularized IPM preserved were all significantly associated (p < 0.001) with new-baseline global GFR. Limitations include the retrospective design and the lack of resection outcome data. Conclusions: Our analysis suggests that TE has potential for maximum IPM preservation compared to SPN and may provide optimized functional recovery. Further investigation will be required to evaluate the clinical significance of these findings. Patient summary: Tumor enucleation for kidney cancer involves dissection along the tumor capsule and optimally preserves normal kidney tissue, which may lead to better functional recovery. The importance of this approach in various clinical settings will require further investigation. Renal tumor enucleation (TE) in renal cancer involves dissection along the pseudocapsule and may optimize preservation of parenchymal mass. The importance of this approach with respect to functional recovery after TE in various settings requires further investigation.
Bibliographical noteFunding Information:
Our study suggests that TE may improve preservation of normal parenchymal mass compared to SPN, and thus has the potential to optimize functional recovery after PN. The main advantage of TE may be related to the reduction in parenchymal mass excised rather than elimination of the need for capsular closure or hilar occlusion. Further investigation is required to evaluate the clinical significance of functional outcomes for TE in various settings. Author contributions: Steven C. Campbell had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Campbell, Dong, Gupta. Acquisition of data : Dong, Gupta, Blackwell, Wu, Suk-Ouichai, Shah, Capodice, Quek, Caraballo Antonio, Aguilar Palacios. Analysis and interpretation of data: Campbell, Dong, Gupta. Drafting of the manuscript: Campbell, Dong, Gupta, Blackwell, Wu, Suk-Ouichai. Critical revision of the manuscript for important intellectual content : Campbell, Dong, Gupta, Remer, Zabell, Isharwal. Statistical analysis: Li, Dong. Obtaining funding: None. Administrative, technical, or material support: None. Supervision: Campbell. Other: None. Financial disclosures: Steven C. Campbell certifies that all conflicts of interest, including specific financial interests and relationships and affiliations relevant to the subject matter or materials discussed in the manuscript (eg, employment/affiliation, grants or funding, consultancies, honoraria, stock ownership or options, expert testimony, royalties, or patents filed, received, or pending), are the following: None. Funding/Support and role of the sponsor: None. Acknowledgments: Wen Dong is funded by the China Scholarship Council (No. 201506385037 ).
- Functional recovery
- Localized renal cell carcinoma
- Parenchymal mass preservation
- Partial nephrectomy
- Tumor enucleation