MRI texture analysis in predicting treatment response to neoadjuvant chemoradiotherapy in rectal cancer.

Yankai Meng,Chongda Zhang,Chunwu Zhou,Xinming Zhao,Shuangmei Zou,Hongmei Zhang,Kai Xu

doi:10.18632/oncotarget.23813

Abstract

To evaluate the importance of MRI texture analysis in prediction and early assessment of treatment response before and early neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC). This retrospective study comprised of 59 patients. The tumoral texture parameters were compared between pre- and early nCRT. Area Under receiver operating characteristic (ROC) Curves [AUCs] were used to compare the diagnostic performance of statistically significant difference parameters and logistic regression analysis predicted probabilities for discriminating responders and nonresponders. The Standard Deviation (SD), kurtosis and uniformity were statistically significantly difference between pre- and early nCRT (p = 0.0012, 0.0001, and < 0.0001, respectively). In pathological complete response (pCR) group, pre-uniformity and pre-Energy were significantly higher than that of nonresponders (p = 0.03 and p < 0.01, respectively), while the pre-entropy in nonresponder was reverse (p = 0.01). The diagnostic performance of pre-kurtosis and pre-Energy were higher in tumor regression grade (TRG) and pCR group (AUC = 0.67, 0.73, respectively). Logistic regression analysis showed that diagnostic performance for prediction responder and nonresponder did not significantly improve compared with to pre-uniformity, energy and entropy in pCR group (AUC = 0.76, p = 0.2794, 0.4222 and 0.3512, respectively). Texture parameters as imaging biomarkers have the potential to prediction and early assessment of tumoral treatment response to neoadjuvant chemoradiotherapy in patients with LARC.

Highlights

Neoadjuvant chemoradiotherapy followed by total mesorectal excision (TME) is the recommended standard therapy for patients with locally advanced rectal cancer (LARC) [1,2,3]
We demonstrated the reliable use of Texture analysis (TA) parameters extracted from conventional T2WI for prediction and early assessment of treatment response of LARC to nRCT according to two different pathological reference standards
Our results showed that most of the texture parameters decreased at the third of week of CRT, with the exception of Standard Deviation (SD) and entropy

Summary

Introduction

Neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME) is the recommended standard therapy for patients with locally advanced rectal cancer (LARC) [1,2,3] This treatment strategy has improved locoregional control, and rates of sphincter preservation [1, 2] and lead to significant pathologic complete response (pCR) defined as the absence of viable tumor cells after full pathologic examination of the resected specimen (ypT0N0M0) in a significant proportion of patients [4, 5]. Different MRI biomarkers including tumor volume, apparent diffusion coefficient (ADC) values, perfusion parameters of dynamic contrastenhanced MRI (DCE-MRI), and parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) have been investigated [8,9,10,11] These imaging markers have limitations in predicting treatment response. Studies prove that DCE-MRI and IVIM-DWI modalities are useful in treatment response of rectal cancer, these studies are still in extremely preliminary stages [11, 14]

Objectives

Methods

Results

Conclusion