3.0 T MRI IVIM-DWI for predicting the efficacy of neoadjuvant chemoradiation for locally advanced rectal cancer

Abstract

Purpose The purpose of this study was to determine the diagnostic performance of intravoxel incoherent motion (IVIM) on assessing response to neoadjuvant chemoradiation (nCRT) in patients with Locally Advanced Rectal Cancer (LARC). Methods 50 patients with rectal cancer who underwent magnetic resonance (MR) imaging before and after nCRT, the values of pre-nCRT and post-nCRT IVIM-DWI parameters apparent diffusion coefficient (ADC), diffusion coefficient (D), false diffusion coefficient (D*), and perfusion fraction (f), together with the percentage changes (∆% parametric value) induced by nCRT were calculated. According to the patient's response to nCRT, the patients were divided into pathological complete response (pCR) and non-pCR groups, Good Response (GR) group and Poor Response (PR) group, and the above values were compared between different groups. Univariate and multiple logistic regression analysis were done to investigate the relation between different parameters and patient nCRT. Draw ROC curve according to sensitivity and specificity, and compare its diagnostic efficacy. Results There were no significant differences in the baseline data of 50 patients. After nCRT, the ADC and D values for LARC increased significantly (all p < 0.05). The pCR group (n = 9) had higher preD*, pref, postD*, ∆%ADC and ∆%D values than the non-pCR group (n = 41) (all p < 0.05). The GR group (n = 17) exhibited higher post D, ∆%ADC and ∆%D values than the PR group (n = 33) (all p < 0.05). From the results of Logistic regression analysis found that ∆%ADC and ∆%D were significantly correlated with patients' response to nCRT. Based on ROC analysis, ∆%D had a higher area under the curve value than ∆%ADC (p = 0.009) in discriminating the pCR from non-pCR groups. Conclusions IVIM-DWI technology may be helpful in identifying the pCR and GR patients to nCRT for LARC.

Combination of intravoxel incoherent motion histogram parameters and clinical characteristics for predicting response to neoadjuvant chemoradiation in Rectal Cancer

“…As described previously [16,17], our result indicated that f_mean and f_median values were higher in the pCR group compared with the non-pCR group, and these values were positively correlated with the TRG. Microvascular volume fraction f re ects the proportion of microenvironment perfusion and it is associated with vascularization [42].…”

“…Nevertheless, the free motion of water molecules in the human body is affected by many factors such as cell membrane, protein, and especially microcirculation blood perfusion, so the ADC may not accurately re ect the diffusion of water molecules [15]. Several studies have proposed an Intravoxel Incoherent Motion (IVIM) to separate blood perfusion from true diffusion of water molecules, which shows potential advantages in treatment response prediction in LARC patients [16][17][18][19]. The IVIM model could distinguish perfusion effects utilizing multiple b value sampling and a biexponential curve t analysis and produce three parameters including true diffusion coe cient (D), false diffusion coe cient (D * ), and perfusion fraction (f) [20].…”

Role of IVIM MRI in staging and restaging of rectal cancer

“…In the present meta-analysis, more than 75% of the studies were of low risk of bias regarding the random sequence generation (selection bias), while more than 50% of the studies were of low risk of bias regarding the allocation concealment (selection bias) (11)(12)(13)(14)(15)(16) and incomplete outcome data (attrition bias) (17,18).…”

Combining Clinicopathology, IVIM-DWI and Texture Parameters for a Nomogram to Predict Treatment Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer Patients

“…Hu et al. found that in rectal cancer patients who received nCRT, the f value of the pCR group was significantly higher than that of the non-pCR group ( 42 ). Bakke et al.…”