Preoperative and intraoperative observations may differ during laparoscopic nephron-sparing surgery

Purpose: We retrospectively reviewed the preoperative radiologic findings and operational videos of a group of patients who were undergoing laparoscopic nephron-sparing surgery (NSS), to determine whether we should decide the operational approach (laparoscopic vs open or radical nephrectomy) on the basis of only the preoperative aspects and dimensions used for an anatomic (PADUA) classification. Patients and Methods: In total, 41 laparoscopic NSS operations were performed during a 34-month period for suspicious solid renal lesions. Clinicopathologic variables, PADUA scores, operative parameters, and renal functional outcomes were prospectively recorded and analyzed. Meanwhile, a similar classification (intraoperative aspects and dimensions used for an anatomic [IADUA] classification) was used to compare the preoperative imaging modality findings with intraoperative findings. Results: There was a 73.2% difference between PADUA and IADUA scores. Sixteen (39%) patients had PADUA scores >IADUA scores, 14 (34%) had PADUA scores <IADUA scores, and only 11 (27%) had similar PADUA and IADUA scores. For the study cohort, the mean operative time (OT) was 128 minutes (range 50-250) min, the mean estimated blood loss (EBL) was 199 mL (range 10-1000 mL), the mean warm ischemia time was 35.2 minutes (range 15-60 min), and the mean change in glomerular filtration rate was 8.17 mL/min/1.73m ² (range -41-26 mL/min/1.73m ²). The mean pathologic tumor size was 32.7±12.3 mm. Thirteen complications were recorded according to the modified Clavien system. PADUA and IADUA were not correlated with EBL and OT, and higher scores failed to predict perioperative complications. Conclusions: Reproducible standardized classification systems are necessary for renal masses. Intraoperative findings for renal masses, however, may differ from the preoperative radiologic evaluation. Thus, the decision for the type of surgical approach should not be based solely on preoperative assessment, such as the PADUA score.