Implementation and external validation of Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score for predicting complications in 74 consecutive partial nephrectomies.

UNLABELLED

Study Type - Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Partial nephrectomy (PN) is the gold standard operation for small renal tumours. The decision for or against a PN has been based mostly on preoperative radiological evaluation of the tumour. Three nephrometry scoring systems have been recently proposed for prediction of postoperative complications of PN (RENAL, C-index and PADUA). We validate externally the accuracy of the PADUA system and suggest for the first time a novel scoring system, based on the original PADUA system, which implements three other significant factors for the postoperative course of a partial.

OBJECTIVE

• To externally validate the Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) classification of renal tumours managed by partial nephrectomy (PN).

PATIENTS AND METHODS

• Seventy-four consecutive patients in a single academic tertiary institution underwent open PN. • Incidence of 90-day complications was stratified by several clinicopathological variables, such as gender, age of the patient, hospital stay, pathology report, tumour characteristics and positive surgical margins. PADUA scores were given to each case. • The severity of complications was also categorized with the Clavien system.

RESULTS

• The optimal threshold of PADUA for the prediction of complications was 8 with a sensitivity equal to 90.9% and a specificity equal to 77.8% (area under the curve [AUC], 0.89; 95% confidence interval [CI], 0.73-1.00). • Multivariate analysis revealed that that PADUA is an independent predictor for the risk of complications. • Also, PADUA score ≥ 8 identified a group of patients with almost 20-fold higher risk of complications (hazard ratio [HR]= 19.82; 95% CI, 1.79-28.35; P= 0.015). • Patients with papillary histology had greater risk for complications than those with clear-cell tumours (HR = 4.88; 95% CI, 1.34-17.76; P= 0.016).

CONCLUSIONS

• The PADUA score is a simple anatomical system that predicts the risk of postoperative complications. This is the first external validation of this system for open PN from a single centre. • The authors believe that PADUA is an efficient tool, since the only variable of the present study that predicted a higher incidence of complications was the histology type, which is determined after surgery. • However, it should be applied to laparoscopic and robot-assisted series and it could also include the ischaemia time and surgeon experience in the overall scoring to be complete.