Conversion of Robot Assisted Partial Nephrectomy to Radical Nephrectomy; a Prospective Multi-Institutional Study

To assess the incidence, and factors affecting conversion from robot-assisted partial nephrectomy (RAPN) to radical nephrectomy.

Between November 2014 and February 2017, 501 patients underwent attempted RAPN by 22 surgeons at 14 centers in nine countries within the Vattikuti Collaborative Quality Initiative database. Patients were permanently logged for RAPN prior to surgery and were analysed on an intention-to-treat basis. Multivariable logistic regression with backward stepwise selection of variables was done to assess the factors associated with conversion to radical nephrectomy.

Overall conversion rate was 25/501 (4.99%). Patients converted to radical nephrectomy were older (median age [interquartile range] 66.0 [61.0-74.0] vs 59.0 [50.0-68.0], P=0.012), had higher body mass index (median 32.8 [24.9-40.9] vs. 27.8 [24.6-31.5] Kg/m2, P = 0.031), higher age-adjusted Charlson comorbidity score (median 6.0 [4.0-7.0] vs. 4.0 [3.0-5.0], P < 0.001), higher American Society of Anesthesiologists score (Score ≥3; 13/25 (52.0%) vs 130/476 (27.3%), P = 0.021), Preoperative estimated glomerular filtration rate (P=0.141), clinical tumor stage (P=0.145), tumor location (P=0.140), multifocality (P=0.483) and RENAL nephrometry score (P=0.125) were not significantly different between the groups. On multivariable analysis, independent predictors for conversion were BMI (odds ratio [95% CI]; 1.070 [1.018-1.124]; P = 0.007), and Charlson score (odds ratio [95% CI]; 1.459 [1.179-1.806]; P = 0.001).

RAPN was associated with a low rate of conversion. Independent predictors of conversion were body mass index and Charlson score. Tumor factors such as clinical stage, location, multifocality, or RENAL score were not associated with increased risk of conversion.

Urology. 2017 Dec 25 [Epub ahead of print]

Sohrab Arora, Brian Chun, Rajesh K Ahlawat, Ronney Abaza, James Adshead, James R Porter, Benjamin Challacombe, Prokar Dasgupta, Giorgio Gandaglia, Daniel A Moon, T B Yuvaraja, Umberto Capitanio, Alessandro Larcher, Francesco Porpiglia, Alexander Mottrie, Mahendra Bhandari, Craig Rogers

Vattikuti Urology Institute, Henry Ford Hospital, Detroit, MI, USA. Electronic address: ., Vattikuti Urology Institute, Henry Ford Hospital, Detroit, MI, USA., Fortis Escorts Kidney and Urology Institute, New Delhi, India., Fortis Escorts Kidney and Urology Institute, New Delhi, India; Department of Urology, Ohio Health Dublin Methodist Hospital, Dublin, OH, USA., Hertfordshire and South Bedfordshire Urological Cancer Centre, Lister Hospital, Stevenage, UK., Swedish Medical Center, Seattle, WA, USA., MRC Centre for Transplantation, King's College London, London, UK., Urology Clinic, San Raffaele Hospital, Milan, Italy., Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia., Kokilaben Dhirubhai Ambani Hospital, Mumbai, India., San Luigi Gonzaga Hospital, University of Turin, Orbassano, Turin, Italy., OLV Vattikuti Robotic Surgery Institute, Melle, Belgium.