Introduction

To date no studies assessed whether Charlson Comorbidy Index (CCI), American Society of Anesthesiologists score (ASA) and Eastern Cooperative Oncology Group performance status (ECOG) have the same ability to predict postoperative mortality in renal cell carcinoma (RCC) patients who undergo radical (RN) or partial nephrectomy (PN). The aim of the study was to assess the predictive ability of these indeces on other cause mortality (OCM) in patients treated with surgery for kidney cancer.

Methods

We identified 2,648 T1-T4 patients treated with RN or PN for RCC between 1987 and 2014 at a single centre. Patients with distant metastases at diagnosis, with multiple lesions and with Von Hippel Lindau were excluded. Four multivariable Cox regression analyses (MVA) were performed to assess OCM predictors. Predictors included in Model 1 were age at surgery and gender (basic model). Predictors in Model 2, 3 and 4 were the same included into Model 1 plus CCI, ASA and ECOG, respectively. The discrimination of the accuracy of each model was quantified using the receiver operating characteristic-derived area under the curve with a time frame at 3-year. Decision curve analyses were performed to evaluate and compare the net-benefit associated with the use of the 3 indeces relative to the basic model.

Results

249 patients (9.4%) died of other causes. Overall, 82 (3.1%) patients died within 3 years after surgery. The median follow-up in patients who survived was 63 months (IQR 30-118). At MVA of Model 1, age (HR 1.1) and gender (HR 1.5) were independent predictors of OCM (all p0.004). At MVA of Model 2, 3 and 4, age and gender remained independent predictors of OCM (all p0.04). Furthermore, at MVA of model 2, 3 and 4 CCI (HR 1.3), ASA (HR 1.09) and ECOG (HR 1.9) reached the independent predictor status (all p<0.001). The accuracy of Model 1, 2, 3 and 4 were 74.5 vs 77.6 vs 76.3 vs 76.3. After decision curve analyses, there was no superior net-benefit of one model relative to the others.

Conclusions

We provided evidence that the difference in accuracy between the CCI, ASA and ECOG is clinically negligible. Interestingly, the increase in accuracy relative to the basic model of all three index is limited and there is no superior net-benefit of any of the examined indeces relative to the basic model. These findings suggest that there is an impending need of a disease-specific index to predict OCM in RCC patients submitted to surgery. At the moment, clinicians may use any of these indeces for RCC patients counselling to predict postoperative mortality after surgery.

Funding

none