JU INSIGHT Conversion of Robotic Partial to Radical Nephrectomy Is Often for Anatomic and Oncologic Complexity

By: Yuzhi Wang, MD,* Vattikuti Urology Institute, Henry Ford Health, Detroit, Michigan; Samantha Wilder, MD,* Vattikuti Urology Institute, Henry Ford Health, Detroit, Michigan; Mohit Butaney, MD, Vattikuti Urology Institute, Henry Ford Health, Detroit, Michigan; Mahmoud Hijazi, BS, University of Michigan Medical School, Ann Arbor; David Gandham, BS, University of Michigan Medical School, Ann Arbor; Monica Van Til, MS, University of Michigan Medical School, Ann Arbor; Benjamin Goldman, DO, Ascension Macomb-Oakland Hospital, Warren, Michigan; Ji Qi, MS, University of Michigan Medical School, Ann Arbor; Mahin Mirza, MPH, University of Michigan Medical School, Ann Arbor; Anna Johnson, MS, University of Michigan Medical School, Ann Arbor; Michael Rudoff, DO, Comprehensive Urology, Beaumont Hospital, Royal Oak, Michigan; David Wenzler, MD, Comprehensive Urology, Beaumont Hospital, Royal Oak, Michigan; Craig G. Rogers, MD, Vattikuti Urology Institute, Henry Ford Health, Detroit, Michigan; Brian R. Lane, MD, PhD, Corewell Health Hospital System, Grand Rapids, Michigan, Michigan State University College of Human Medicine, Grand Rapids, for the Michigan Urological Surgery Improvement Collaborative; *Co-first authors. | Posted on: 20 May 2024

Wang Y, Wilder S, Butaney M, et al; Michigan Urological Surgery Improvement Collaborative. Conversion to radical nephrectomy from robotic partial nephrectomy is most commonly due to anatomic and oncologic complexity. J Urol. 2024;211(5):669-676.

Study Need and Importance

Partial nephrectomy is standard-of-care treatment for small renal masses. As utilization of partial nephrectomy increases and includes larger and complex tumors, the risk of conversion to radical nephrectomy increases. There needs to be better understanding of the predisposing factors behind conversions. We evaluated incidence and reason for conversion to radical nephrectomy in patients scheduled for partial nephrectomy by surgeons participating in MUSIC (the Michigan Urologic Surgery Improvement Collaborative).

What We Found

Of 650 patients scheduled for robotic partial nephrectomy, conversion to radical nephrectomy occurred in 27 (4.2%). No conversions to open were reported. Preoperative documentation indicated a plan for possible conversion in 18 (67%) patients including partial with possible radical (n = 8), partial vs radical (n=6), or likely radical nephrectomy (n=4). Intraoperative documentation indicated that only 5 (19%) conversions were secondary to bleeding, with the remaining conversions due to tumor complexity and/or oncologic concerns (Figure). Patients undergoing conversion had larger (4.7 vs 2.8 cm, P < .001) and higher-complexity tumors (64% vs 6%, P < .001) with R.E.N.A.L. (for radius, exophytic/endophytic, nearness of tumor to collecting system, anterior/posterior, location relative to polar line) nephrometry score ≥ 10. The converted cases had a higher rate of ≥ pT3 (27% vs 8.4%, P = .008).

Limitations

As documentation was variable and not explicitly standardized, conclusions that can be made regarding factors associated with conversions and our understanding of pre- and intraoperative decision-making were somewhat subjective. The low number of conversions further limited the generalizability of our results, and we did not have sufficient conversion events to conduct a meaningful multivariable model.

Interpretation for Patient Care

While reported rates of conversion are already low, there is an even lower risk of conversion for bleeding rather than for minimization of oncological risk. Urologists should discuss that a higher risk of conversion and other complication may exist for certain patients rather than having an identical discussion for patients with standard robotic partial nephrectomy.

Figure. Preoperative and intraoperative documentation in the 27 robotic partial nephrectomy (RPN) cases converted to robotic radical nephrectomy (RN). PN indicates partial nephrectomy.