Diffusion-weighted MRI and MR- volumetry--in the evaluation of tumor response after preoperative chemoradiotherapy in patients with locally advanced rectal cancer.

摘要: Abstract Purpose To determine the diagnostic performance of diffusion-weighted MRI and MR volumetry for assessment tumor response after preoperative chemoradiotherapy (CRT) in patients with locally advanced rectal cancer. Materials Methods Forty-three cancer who underwent CRT were prospectively examined study. This prospective study was approved by our institutional review board. DW- high resolution T2-weighted imaging performed before therapy. Two different diffusion gradients (b = 0 b = 600, then separately b = 0 b = 1000) applied. The mean volume ADC values measured evaluate responders nonresponders to neoadjuvant CRT, two criteria, ypT stage determined pathologic examination treatment histopathologic regression grade (Ryan), used as reference standards. a lower than T first evaluated responder group, while higher or same relative nonresponder group. According Ryan grade, 1 responders, whereas grades 2 3 percentage increase compared between using standards: downstaging (TRG). Results Before group significantly that (p  Conclusion treated correlated good response. DW is promising non-invasive technique can help predict monitor early therapeutic undergo CRT.