Conversion of Robot-assisted Partial Nephrectomy to Radical Nephrectomy: A Prospective Multi-institutional Study

Area of Science:

• Urology
• Surgical Oncology
• Robotic Surgery

Background:

• Robot-assisted partial nephrectomy (RAPN) is increasingly used for kidney tumors.
• Understanding conversion rates and predictors is crucial for surgical planning and patient counseling.

Purpose of the Study:

• To determine the incidence of conversion from RAPN to radical nephrectomy.
• To identify patient and tumor factors associated with conversion during RAPN.

Main Methods:

• Analysis of 501 patients undergoing attempted RAPN from the Vattikuti Collaborative Quality Initiative database (Nov 2014 - Feb 2017).
• Intention-to-treat analysis was performed.
• Multivariable logistic regression identified independent predictors of conversion.

Main Results:

• The overall conversion rate was 5% (25/501 patients).
• Converted patients were older, had higher BMI, and higher comorbidity scores (Charlson and ASA).
• Independent predictors for conversion were BMI (OR 1.070) and Charlson score (OR 1.459). Tumor factors were not significant predictors.

Conclusions:

• RAPN demonstrates a low conversion rate to radical nephrectomy.
• Patient factors, specifically BMI and comorbidity burden (Charlson score), are key predictors of conversion.
• Tumor characteristics like stage, location, multifocality, and RENAL score do not significantly influence conversion risk.