Predicting Response to Total Neoadjuvant Treatment (TNT) in Locally Advanced Rectal Cancer Based on Multiparametric Magnetic Resonance Imaging: A Retrospective Study

Abstract

Purpose: To investigate the potential value of magnetic resonance imaging (MRI) in predicting response relevance to total neoadjuvant treatment (TNT) in locally advanced rectal cancer.Methods: We analyzed MRI of 71 patients underwent TNT from 2015 to 2017 retrospectively. We categorized the response of TNT as CR (complete response) and non-CR, and high, moderate and low sensitivity. Logistic regression analysis was used to identify the best predictors of response. Diagnostic performance was assessed using receiver - operating characteristic curve analysis.Results: Post–ICT (induction chemotherapy) ∆TL (tumor length), post-CRT (concurrent chemoradiotherapy) ∆LNN (the numbers of lymph node metastases), post–CCT (consolidation chemotherapy) ∆SDWI (maximum cross-sectional area of tumor on diffusion-weighted imaging), post-CCT ADCT (the mean apparent diffusion coefficient values of tumor) and post-CCT ∆LNV (volume of lymph node) were the best CR predictors. Post-CRT EMVI (extramural vascular invasion) and post-CCT ∆ST2 (S on T2-weight) were the best significant factors for high sensitivity. Conclusions: Post-ICT ∆TL and post-CRT EMVI may an early predictor of CR and high sensitivity to TNT, respectively. The grouping scheme of CR and non–CR was more suitable for predicting response by MRI parameters than high, moderate and low sensitivity.Trial registration: retrospectively registered

Predictors of Positive Circumferential Resection Margin in Rectal Cancer: A Current Audit of the National Cancer Database

“…Identifying these features can help the multidisciplinary team identify the appropriate neoadjuvant, adjuvant, and surgical plans. 6,21,22 We found that nCRT was independently associated with positive CRM; this has been described previously and is likely attributed to selection bias of locally advanced disease for nCRT or tumors resistant to therapy with poor downstaging. 3 It may also reflect compliance with nCRT recommendations, which is complex and multifactorial, 23,24 and the patient understanding of their treatment options, a difficult variable to measure that can contribute to nCRT use and subsequent outcomes, including CRM rate.…”