Novel Predictive Models of Early Death Less Than 1 Year in Patients With Metastatic Renal Cell Carcinoma After Treatment With First-line Tyrosine Kinase Inhibitors

Background: We aimed to develop a modified International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model that can predict early death less than 1 year in patients with metastatic renal cell carcinoma (mRCC) after receiving first-line tyrosine kinase inhibitors (TKIs). Patients and Methods: We retrospectively reviewed records of patients with mRCC treated with first-line TKIs at our institution between 2007 and 2012. The primary endpoint was the rate of early death within 1 year after first-line TKI administration. We determined statistically significant factors predicting early death by performing multiple logistic regression. The modified IMDC model 1 was developed using new variables in addition to the risk criteria of the IMDC model, and model 2 was developed using new variables irrespective of the risk classification of IMDC model. Results: Early mortality within 1 year of first-line TKI treatment was 19.7% (n = 98) in 462 patients. Although the C-index of the IMDC model for early death was 0.655, the C-index of model 1, which includes 5 variables (previous nephrectomy, body mass index, multiple metastases, previous metastasectomy, and serum albumin level) in addition to the Heng criteria, was 0.823. The C-index of model 2, which includes 7 variables (hemoglobin, neutrophil level, and the 5 variables of model 1) was 0.822. Of note, there was no significant difference in net reclassification index between the 2 models. Conclusion: This is the first study suggesting novel prediction models for early death less than 1 year in patients with mRCC treated with first-line TKI. We reviewed the records of 462 patients with metastatic renal cell carcinoma treated with first-line tyrosine kinase inhibitors and developed 2 novel prognostic models that can significantly predict early death less than 1 year in patients with metastatic renal cell carcinoma after receiving first-line tyrosine kinase inhibitors.