Usefulness of dynamic contrast enhanced computed tomography in patients with non-small-cell lung cancer scheduled for radiation therapy.

OBJECTIVE: The goal of this study was to investigate the local tumor blood supply parameters relative tumor blood volume (rTBV) and transfer coefficient (K(trans)) measurable with dynamic contrast enhanced computed tomography (DCE-CT) in patients with non-small-cell lung cancer (NSCLC) scheduled for radiation therapy (RT). MATERIALS AND METHODS: rTBV and K(trans) were measured before RT in 31 patients with clinically inoperable NSCLC (Stages I-III), which received (n=19) or did not receive (n=12) induction chemotherapy (IChT). Possible links between rTBV and K(trans) and time-to-progression (TTP), overall survival (OS) and maximum standardized uptake value (SUV(max)) from fluorodeoxyglucose positron emission tomography as well as histology were analyzed. RESULTS: NSCLC showed a wide range of rTBV and K(trans) values as estimated by DCE-CT (6.4±0.6ml/100ml and 18.2±1.5ml/100ml/min correspondingly). A significant difference in rTBV values in patients with IChT (4.6±0.6ml/100ml) and without IChT (7.5±0.9ml/100ml; p=0.023), depending on the number of cycles of the IChT and the clinical stage was found. A negative correlation between rTBV and TTP was revealed only in RT patients up-staged by FDG-PET/CT from stage III to stage IV (n=7, r=-0.96, p=0.0006). An inverse correlation between K(trans) and TTP (n=24, r=-0.53, p=0.008) was observed in all RT patients. No relevant correlation was detected between rTBV, K(trans) and SUV(max) or histologic subtypes and grading. CONCLUSIONS: Tumor blood supply parameters derived from DCE-CT are useful to characterize tumor vascularization before radiotherapy in patients with NSCLC and data on outcome prediction are supplemented.