Data from: Early treatment response in non-small cell lung cancer patients using diffusion-weighted imaging and functional diffusion maps - a feasibility study

Objective: The aim of this study was to prospectively evaluate the
feasibility of monitoring treatment response to chemotherapy in patients
with non-small cell lung carcinoma using functional diffusion maps (fDMs).
Materials and Methods: This study was approved by the Cantonal Research
Ethics Committee and informed written consent was obtained from all
patients. Nine patients (mean age = 66 years; range = 53–76 years, 5
females, 4 males) with overall 13 lesions were included. Imaging was
performed within two weeks before initiation of chemotherapy and at one,
two, and six weeks after initiation of chemotherapy. Imaging included a
respiratory-triggered diffusion-weighted sequence including three
b-factors (100, 600, and 800 s/mm2). Treatment response was defined by
change in tumor diameter on computed tomography (CT) after two cycles of
chemotherapy. Changes in the apparent diffusion coefficient (ADC) on a
per-lesion basis and the percentages of voxel with significantly increased
or decreased ADCs on fDMs were analyzed using repeated measures analysis
of variance (ANOVA). Changes in tumor size were used as covariate to
examine the ability of ADCs and fDM parameters to predict treatment
response. Results: Repeated measures ANOVA revealed that the percentage of
voxels with increased ADCs on fDMs (p = 0.002) as well as the mean ADC
increase (p = 0.011) were significantly higher in good responders with a
large reduction in tumor size on CT. Conclusion: Our results indicate that
the percentage of voxels with significantly increased ADCs on fDMs seems
to be a promising biomarker for early prediction of treatment response in
patients with non-small cell lung carcinoma. Contrary to averaged values,
this approach allows the spatial heterogeneity of treatment response to be
resolved.