Magnetic resonance based texture parameters as potential imaging biomarkers for predicting long‐term survival in locally advanced rectal cancer treated by chemoradiotherapy

Abstract

Aim The study aimed to investigate whether textural features of rectal cancer on MRI can predict long-term survival in patients treated with long-course chemoradiotherapy.Method Textural analysis (TA) using a filtrationÀhis-togram technique of T2-weighted pre-and 6-week post-chemoradiotherapy MRI was undertaken using TexRAD, a proprietary software algorithm. Regions of interest enclosing the largest cross-sectional area of the tumour were manually delineated on the axial images and the filtration step extracted features at different anatomical scales (fine, medium and coarse) followed by quantification of statistical features [mean intensity, standard deviation, entropy, skewness, kurtosis and mean of positive pixels (MPP)] using histogram analysis. Cox multiple regression analysis determined which univariate features including textural, radiological and histological independently predicted overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS).Results MPP [fine texture, hazard ratio (HR) 6.9, 95% CI: 2.43-19.55, P < 0.001], mean (medium texture, HR 5.6, 95% CI: 1.4-21.7, P = 0.007) and extramural venous invasion (EMVI) on MRI (HR 2.96, 95% CI: 1.04-8.37, P = 0.041) independently predicted OS while mean (medium texture, HR 4.53, 95% CI: 1.58-12.94, P = 0.003), MPP (fine texture, HR 3.36, 95% CI: 1.36-8.31, P = 0.008) and threatened circumferential resection margin (CRM) on MRI (HR 3.1, 95% CI: 1.01-9.46, P = 0.046) predicted DFS. For OS, EMVI on MRI (HR 4.23, 95% CI: 1.41-12.69, P = 0.01) and for DFS kurtosis (medium texture, HR 3.97, 95% CI: 1.44-10.94, P = 0.007) and CRM involvement on MRI (HR 3.36, 95% CI: 1.21-9.32, P = 0.02) were the independent post-treatment factors. Only TA independently predicted RFS on pre-or post-treatment analyses.Conclusion MR based TA of rectal cancers can predict outcome before undergoing surgery and could potentially select patients for individualized therapy.

Application and Progress of Texture Analysis in the Therapeutic Effect Prediction and Prognosis of Neoadjuvant Chemoradiotherapy for Colorectal Cancer

“…Chee et al [21] found that homogeneous texture features (higher Uniformity, lower Entropy and lower SD) were connected with higher DFS in patients with locally advanced rectal cancer. Jalil et al [33] used texture analysis based on MRI to find that Kurtosis was the independent factor to predict DFS for CRC patients.…”

Radiomic features based on MRI for prediction of lymphovascular invasion in rectal cancer

“…Rectal MRI is essential for pre-and post-treatment assessment of rectal cancer, as it provides anatomic structures and their relationship with the tumor with a high-spatial resolution [22,23]. Rectal MRIbased radiomics have been used for treatment response [24], lymph-node metastasis [25], and prognostic evaluation [26]. However, MRI-based radiomics for LVI prediction remains underinvestigated in rectal cancer.…”

Response to neoadjuvant chemoradiotherapy for locally advanced rectum cancer: Texture analysis of dynamic contrast‐enhanced MRI

“…Features obtained from TA have been used to help distinguish abnormal from normal tissues in the lung, liver, colon, breast, and prostate . MRI‐based TA of rectal cancers can assess the outcome and thus could potentially be used to select patients for individualized therapy . TA also can be used to evaluate the efficacy of radiotherapy.…”

“…[16][17][18] MRI-based TA of rectal cancers can assess the outcome and thus could potentially be used to select patients for individualized therapy. 19 TA also can be used to evaluate the efficacy of radiotherapy. A few studies have focused on DCE-MRI scans to assess the pathological response after preoperative CRT for LARC, 19,20 although those studies mostly considered rectal cancer as a uniform mass or used a mean value to describe the whole tumor.…”