New prognostic model for synchronous metastatic renal cell carcinoma

To create a new model for the prediction of overall survival in synchronous metastatic renal cell carcinoma.

Medical records of 158 patients with metastatic renal cell carcinoma diagnosed at the Yamagata University Hospital from August 2007 to February 2018 were reviewed. Among them, 77 with synchronous metastatic renal cell carcinoma were retrospectively analyzed using the univariate and multivariate analyses. A new prognostic model was constructed, followed by a bootstrap validation to estimate the model fitting. In addition, these prognostic factors were estimated in 67 metachronous metastatic renal cell carcinoma patients.

Five independent prognostic factors were identified in synchronous metastatic renal cell carcinoma: cT3/4, cN1, high corrected calcium, >3.6 neutrophil-to-lymphocyte ratio and central nerve system metastasis. The number (%) and overall survival (95% confidence interval) in the favorable- (0 or 1 risk factor), intermediate- (2 risk factors) and poor-risk (≥3 risk factors) groups were 29 (45.3%) and 67.4 (31.8-NA), 21 (32.8%) and 16.8 (10.0-27.6), and 14 (21.9%) and 9.1 (7.3-13.7) months, respectively. The C-index was 0.72. Patients in the favorable-risk group had better overall survival with nephrectomy than without nephrectomy (hazard ratio 0.29, 95% confidence interval 0.09-0.91 with nephrectomy). In metachronous metastatic renal cell carcinoma, these prognostic factors showed no statistical differences in the overall survival.

Prognostic factors are completely different between synchronous and metachronous metastatic renal cell carcinoma. The new model for synchronous metastatic renal cell carcinoma can predict a good candidate for cytoreductive nephrectomy.