Importance of performance status, corrected calcium, and microvascular invasion in predicting overall survival in patients with metastatic renal cell carcinoma at the era of molecular targeted therapy.

e15588 Background: We have recently reported that the single nucleotide polymorphisms (SNPs) in signal transducer and activator 3 (STAT3) gene are significantly associated with better response to interferon (IFN)-α in patients with metastatic renal cell carcinoma (mRCC) in our prospective trail (Eur Urol 2012, Epub ahead). In the present study, we further evaluated which clinical and pathological factors correlated with overall survival (OS) in the trial. Methods: In the multicenter, prospective study, patients with histologically confirmed RCC that was metastatic, measurable disease, age > 20 years, ECOG performance status (PS) 0-1 and adequate organ function received 3 dosages of 5 million U per week of IFN-α treatment. After the failure of IFN-α, molecular targeted drugs were used. We followed the patients for 2 years to define the date of death or loss to follow-up to calculate OS. Association between OS and clinical, pathological factors, such as age, PS, TNM classification, grade, infiltrating type,...