J Clin Oncol 2017 Dec 4;35(36):4057-4065. Epub 2017 Aug 4.
Carole Fakhry, Johns Hopkins University, Baltimore, MD; Qiang Zhang and Jonathan Harris, NRG Oncology Statistics and Data Management Center, American College of Radiology; John A. Ridge, Fox Chase Cancer Center, Philadelphia, PA; Phuc Felix Nguyen-Tân and Louise Lambert, Centre Hospitalier de l'Université de Montréal, Montreal; Eric Vigneault, L'Hotel-Dieu de Quebec, Ville de Québec, Quebec, Canada; David I. Rosenthal, Randal S. Weber, and Maura L. Gillison, MD Anderson Cancer Center, Houston, TX; Andy M. Trotti III, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL; William L. Barrett, University of Cincinnati Cancer Institute, Cincinnati, OH; Wade L. Thorstad, Washington University, St Louis, MO; Christopher U. Jones, Sutter General Hospital, Sacramento; Sue S. Yom, University of California San Francisco, San Francisco; Shyam S.D. Rao, University of California Davis, Davis; Quynh-Thu Le, Stanford University, Stanford, CA; Stuart J. Wong, Medical College of Wisconsin, Milwaukee, WI; James A. Bonner, University of Alabama at Birmingham Medical Center, Birmingham, AL; David Raben, University of Colorado, Aurora, CO; and Mahesh R. Kudrimoti, University of Kentucky, Lexington, KY.
Purpose Treatment of oropharyngeal squamous cell carcinoma (OPSCC) is evolving toward risk-based modification of therapeutic intensity, which requires patient-specific estimates of overall survival (OS) and progression-free survival (PFS). Methods To develop and validate nomograms for OS and PFS, we used a derivation cohort of 493 patients with OPSCC with known p16 tumor status (surrogate of human papillomavirus) and cigarette smoking history (pack-years) randomly assigned to clinical trials using platinum-based chemoradiotherapy (NRG Oncology Radiation Therapy Oncology Group [RTOG] 0129 and 0522). Nomograms were created from Cox models and internally validated by use of bootstrap and cross-validation. Model discrimination was measured by calibration plots and the concordance index. Nomograms were externally validated in a cohort of 153 patients with OPSCC randomly assigned to a third trial, NRG Oncology RTOG 9003. Results Both models included age, Zubrod performance status, pack-years, education, p16 status, and T and N stage; the OS model also included anemia and age × pack-years interaction; and the PFS model also included marital status, weight loss, and p16 × Zubrod interaction. Predictions correlated well with observed 2-year and 5-year outcomes. The uncorrected concordance index was 0.76 (95% CI, 0.72 to 0.80) for OS and 0.70 (95% CI, 0.66 to 0.74) for PFS, and bias-corrected indices were similar. In the validation set, OS and PFS models were well calibrated, and OS and PFS were significantly different across tertiles of nomogram scores (log-rank P = .003;< .001). Conclusion The validated nomograms provided useful prediction of OS and PFS for patients with OPSCC treated with primary radiation-based therapy.