MR diffusion weighted imaging with background signal suppression in breast cancer

Abstract

Objective To explore the feasibility of echo planar imaging with short time inversion recovery(STIR-EPI)diffusion weighted imaging with background signal(DWIBS)suppression in breast cancer.Methods The diffusion weighted imaging(DWI)with background suppression(b=800 mm2/s)was performed in 26 patients with breast cancer.Apparent diffusion coefficient(ADC)of all lesions,vere measured and compared.3D maximum intensity projection(3D-MIP)and reverse black and white technique were used to show the lesions.DWI and DWIBS were performed and compared for the detection of breast cancer. Randomized blocks analysis of variance was used for the ADC values in different breast tissues.the ADC values in breast cancer and benign lesion were compared using t test.The paired chi square tes:was used for the detection rate of breast cancer in two different imaging methods.Results Most of the breast cancers were hyperintense on DWI(b:800 mm2/s).,rhe ADC value of caneer tissue was(0.93±0.25)×10-3mm2/s,tumor necrosis was(2.06±0.17)×10-3 mm2/s,normal breast tissue was (1.92±0.23)×10-3 mm2/s and metastatic lymph node was(1.10±0.14)× 10-3mm2/s and the differenees were statistically significant between two structures(P＜0.01).The signal of the tissue8 around the breast cancer was decreased on DWIBS with 3 D-MIP and reverse black and white technique and similar to positron emission tomography(PET).DWIBS sequence detected more breast cancers(92.3/)and metastatic lymph nodes(88.4/)than DWI sequence did(57.6/and 42.3/,respectively,X2:8.307,P＜0.05;X2=12.235,P＜0.05).The ADC values in breast cancer(1.09±0.17)×10-3mm2/s and benign lesion (2.15±0.53)×10-3 mm2/s had significant statistical differences(t=8.626,P＜0.05).conclusion Diffusion weighted MRI with background suppression can detect more lesions than DWI and can be potentially applied for the detection of the breast cancer eombining the ADC value. Key words: Breast neoplasms;  Magnetic resonance imaging