title: Conditional survival of metastatic renal cell carcinoma patients treated with high-dose interleukin-2.
abstract: Conditional survival (CS) is a clinically useful prediction measure which adjusts a patient's prognosis based on their duration of survival since initiation of therapy. CS has been described in numerous malignancies, and recently described in patients with metastatic renal cell carcinoma (mRCC) who received vascular endothelial growth factor tyrosine kinase inhibitor (VEGFTKI) therapy. However, CS has been not reported in the context of mRCC treated with high-dose interleukin-2 therapy (HDIL-2). A total of 176 patients with histologically confirmed metastatic clear cell RCC (mccRCC) treated with HDIL-2 at the University of Utah Huntsman Cancer Institute from 1988-2012 were evaluated. Using the Heng/IMDC model, they were stratified by performance status and prognostic risk groups. Two-year CS was defined as the probability of surviving an additional two years from initiation of HDIL-2 to 18 months after the start of HDIL-2 at three-month intervals. The median overall survival (OS) was 19.9 months. Stratifying patients into favourable (n = 35; 20%), intermediate (n = 110; 63%), and poor (n = 31; 18%) prognostic groups resulted in median OS of 47.5 (HR 0.57, 95% CI 0.35-0.88, p = 0.0106 versus intermediate), 19.6 (HR 0.33, 95% CI 0.10-0.33, p < 0.0001 versus poor), and 8.8 (HR 5.34, 95% CI 3.00-9.62, p < 0.0001 versus favourable) months respectively. Two-year overall CS increased from 43% at therapy initiation to 100% at 18 months. These results have significant ramifications in prognostication. Furthermore, it is important when counseling patients with mccRCC who have completed treatment with HDIL-2 and are in active follow-up.
authors.affiliation: University of Utah Huntsman Cancer Institute, Salt Lake City, UT 84112, USA; Equal contribution.
authors.forename: David M
authors.initials: DM
authors.lastname: Gill
authors.affiliation: Department of Pharmacotherapy, College of Pharmacy, University of Utah, Salt Lake City, UT 84112, USA; Equal contribution.
authors.forename: David D
authors.initials: DD
authors.lastname: Stenehjem
authors.affiliation: Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
authors.forename: Kinjal
authors.initials: K
authors.lastname: Parikh
authors.affiliation: Department of Internal Medicine, Vanderbilt University, Nashville, TN 37232, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Merriman
authors.affiliation: University of Cincinnati Medical Center, Cincinnati, OH 45219, USA.
authors.forename: Arun
authors.initials: A
authors.lastname: Sendilnathan
authors.affiliation: Department of Pathology and ARUP Laboratories, The University of Utah, Salt Lake City, UT 84108, USA.
authors.forename: Archana M
authors.initials: AM
authors.lastname: Agarwal
authors.affiliation: University of Utah Huntsman Cancer Institute, Salt Lake City, UT 84112, USA.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Hahn
authors.affiliation: University of Utah Huntsman Cancer Institute, Salt Lake City, UT 84112, USA.
authors.forename: Sumati
authors.initials: S
authors.lastname: Gupta
authors.affiliation: University of Utah Huntsman Cancer Institute, Salt Lake City, UT 84112, USA.
authors.forename: Srinivas Kiran
authors.initials: SK
authors.lastname: Tantravahi
authors.affiliation: Department of Pathology and ARUP Laboratories, The University of Utah, Salt Lake City, UT 84108, USA; Comprehensive Cancer Centers of Nevada, Las Vegas, NV 89148, USA.
authors.forename: Wolfram E
authors.initials: WE
authors.lastname: Samlowski
authors.affiliation: University of Utah Huntsman Cancer Institute, Salt Lake City, UT 84112, USA.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Agarwal
keywords: conditional survival; high-dose interleukin-2; metastatic renal cell cancer