Laparoscopic partial nephrectomy: risk stratification according to patient and tumor characteristics

Laparoscopic partial nephrectomy (LPN) is the treatment of choice for localized tumors in many centers. We aimed to evaluate differences in complication rates and outcome stratified by risk categories, depending on patient or tumor characteristics.

Eighty-one patients who underwent LPN for localized renal tumors between 2004 and 2007 were evaluated. Clinical and pathological data, including localization, size and infiltration depth (classified according to PADUA and RENAL score), at initial radiologic imaging were analyzed. Results were correlated with complications during or after surgery, operative time, warm ischemia time and clinical outcome.

Overall complication rate was 13.6% for LPN (11 patients, Clavien-Dindo classification: II-III). No significant correlations were found for patient-based risk classification models (age > 70 years, ASA-status >2, BMI > 30). A higher mean operative time was observed in centrally located tumors (P = 0.045). Increased hemoglobin loss was observed in central (P = 0.007), PADUA > 8 (P = 0.006) and RENAL > 7 (P = 0.002) tumors. Impaired renal function (creatinine increase in postoperative controls) was associated with tumor diameter > 4 cm (P = 0.023). Only central tumor growth had a significant predictive value for postoperative complications (P = 0.007). In patients with central tumor growth (P = 0.002), PADUA > 8 (P = 0.041) and RENAL > 7 (P = 0.044) scores, hospital stay was prolonged.

Uni and multifactorial scoring systems have been developed for LPN to identify potentially high-risk patients. In our series, only central tumor growth pattern enabled the prediction of increased operation time, hemoglobin loss, hospitalization as well as postoperative complications.