Combined value of apparent diffusion coefficient-standardized uptake value max in evaluation of post-treated locally advanced rectal cancer

• 作者: Cammillo Talei Franzesi Chiara Trattenero Davide Fior Davide Ippolito Elena De Ponti Luca Guerra Sandro Sironi Silvia Drago
• 来源期刊: 世界放射学杂志：英文版（电子版）
• 学科: 医学
• 关键词: Advanced RECTAL cancer Functional IMAGING FDG-PET/CT Magnetic resonance IMAGING APPARENT diffusion coefficient NEOADJUVANT treatment Tumor regression grade
• 年，卷（期）: 2015,（12）
• 页码范围: 509-520
• 页数: 12页
• 分类号: R445.2

摘要

AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient（ADC） and standardized uptake value（SUV）max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body 18FDG positron emission tomography（PET）/computed tomography（CT） scan and a pelvic magnetic resonance（MR）examination including diffusion weighted（DW） imaging for staging（PET1,RM1） and after completion（6.6 wk）of neoadjuvant treatment（PET2,RM2）.Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet（Philips,Achieva）,included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax（△SUV） and ADC（△ADC） values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade（Mandard’s criteria;TRG1 = complete regression,TRG5 = no regression）.RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard’s criteria,22 tumors showed complete（TRG1） or subtotal regression（TRG2） and were classified as responders;9tumors were classified as non responders（TRG3,4 and5）.Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2（P < 0.001）,whereas the mean ADC values was lower in RM1 than RM2（P < 0.001）,with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2（threshold of4.4） and ADC2(1.29 × 10-3 mm2/s) with high sensitivity and specificit