Has the Practice of Radiation Oncology for Locally Advanced and Metastatic Non-Small-Cell Lung Cancer Changed in Canada?

Abstract

Accurate prediction of outcome in advanced non-small-cell lung cancer (NSCLC) remains challenging. Even within the same stage and treatment group, survival and response to treatment vary. We set out to determine the predictive value of inflammatory markers C-reactive protein (CRP) and white blood cells (WBCS) in patients with advanced NSCLC. Patients were assigned a prognostic index (PI): 0 for crp 10 mg/L or less and WBCS 11x10⁹/L or less, 1 if one of the two markers was elevated, and 2 if both markers were elevated. We then used chest computed tomography (CT) imaging to evaluate response after 2 cycles of chemotherapy treatment. Of 134 patients, 46 had a PI of 0; 60, a PI of 1; and 28, a PI of 2. Disease progressed in 41 patients. Progression was significantly more frequent among patients with a PI of 2 (p = 0.008). Median survival was 20.0 months for the PI 0 group, 10.4 months for the PI 1 group, and 7.9 months for the PI 2 group (p < 0.001). The PI was the only significant prognostic factor for survival even after adjustment for performance status, smoking, and weight loss (hazard ratio: 1.57; 95% confidence interval: 1.2 to 2.14; p = 0.004). Inflammatory state correlates significantly with both chemotherapy response and survival in stage IV NSCLC. The PI may provide additional guidance for therapeutic decision-making.