Prognostic implications of diffusion-weighted magnetic resonance imaging in patients with superior sulcus tumors receiving induction chemoradiation therapy

The aim of this study was to evaluate a diffusion-weighted magnetic resonance imaging to represent therapeutic response of induction chemoradiation and outcome in patients with non-small cell lung cancer of the superior sulcus. Seventeen patients with non-small cell lung cancer of the superior sulcus (median age, 57 years; range, 44-70 years) received induction chemoradiation, followed by surgery. Diffusion-weighted magnetic resonance imaging of the lesion using b values of 0 and 800 s/mm(2) was acquired before treatment and after induction chemoradiation. Changes in tumoral apparent diffusion coefficient were compared with clinical and histopathological response. Cumulative disease-free survival and proportion of surviving were estimated by the Kaplan-Meier method. Survival of diffusion responders and non-responders were compared by log-rank test. A significant correlation was observed between changes of diffusion response after induction chemoradiation and overall survival. Using a defined threshold of percent increase in mean apparent diffusion coefficient, nine out of 17 patients (53%) were classified as diffusion responders and had a mean increase in mean apparent diffusion coefficient of 40.7 +/- 11.2%, while eight diffusion non-responding patients (47%) had a mean increase of 11.0 +/- 15.5% (P < 0.0001). Significant difference was found in overall survival between diffusion responders and diffusion non-responders (88.9 months versus 20.3 months, P = 0.002). Diffusion-weighted magnetic resonance imaging represented therapeutic effect and prognosis after induction chemoradiation in patients with non-small cell lung cancer of the superior sulcus.