A novel preoperative evaluation technique for partial nephrectomy: three-dimensional extended renal tumor plane

Area of Science:

• Urology
• Surgical Oncology
• Medical Imaging

Background:

• Robotic-assisted partial nephrectomy (RAPN) is a standard treatment for localized renal tumors.
• Accurate pre-operative planning is crucial for successful RAPN outcomes.
• The trifecta (warm ischemic time ≤ 25 min, negative margins, no major complications) is a key metric for RAPN success.

Purpose of the Study:

• To develop and evaluate a novel three-dimensional (3D) image-based extended tumor plane technique for RAPN planning.
• To assess the impact of the extended tumor plane's relationship with the collecting system on RAPN outcomes.

Main Methods:

• A prospective study of 215 patients undergoing RAPN for localized renal tumors (March 2019 - March 2022).
• Three-dimensional virtual models were reconstructed from computed tomography urography.
• The tumor plane was extended by 10 mm to create a virtual plane, categorizing patients based on collecting system involvement (none, medulla, or calyx).

Main Results:

• The median preoperative aspects and dimensions for an anatomical (PADUA) score was 9.
• The average warm ischemic time was 21.64 ± 9.35 minutes, with 6.5% major perioperative complications.
• Trifecta failure rates were 5.3% (no involvement), 20.6% (medulla involvement), and 40.0% (calyx involvement) (p < 0.001).
• Renal calyx involvement was identified as a significant risk factor for trifecta failure (OR = 2.639, p = 0.009).

Conclusions:

• The 3D image-based extended tumor plane technique is a valuable tool for evaluating RAPN.
• Involvement of the collecting system, especially the renal calyx, by the extended tumor plane is associated with a higher risk of trifecta failure in RAPN.