In a retrospective study evaluating imaging biomarkers for rectal oncology, researchers investigated the prognostic utility of baseline magnetic resonance imaging characteristics derived from the DISTANCED structured report for individuals diagnosed with MRI-defined T3 rectal cancer. The primary objective focused on evaluating whether specific baseline imaging markers could reliably predict disease-free survival following standard curative-intent treatment protocols. Analysis revealed that baseline MRI-determined lateral lymph node metastasis, circumferential resection margin involvement, and tumor deposits serve as significant independent predictors of disease-free survival.
The study cohort comprised 190 patients diagnosed with MRI-defined T3 rectal cancer treated between December 2014 and June 2023. All enrolled participants underwent neoadjuvant therapy followed by definitive surgical resection. Across the overall study population, patient monitoring extended across a median follow-up duration of 43 months, encompassing an observed range from 2 months to 126 months. Investigators systematically assessed baseline magnetic resonance imaging features alongside relevant clinical characteristics and long-term follow-up records.
To establish and independently evaluate predictive performance, the 190 patients were randomly partitioned into two separate groups according to a 7:3 allocation ratio. This process yielded a primary training cohort of 133 patients dedicated to model discovery and construction, as well as an independent internal validation cohort consisting of 57 patients reserved for testing model reproducibility and generalizability across unseen cases.
Within the training cohort, investigators conducted multivariable Cox regression analyses to isolate independent risk factors associated with disease-free survival. The features identified through regression modeling—specifically lateral lymph node metastasis, circumferential resection margin status, and the presence of tumor deposits on baseline imaging—were subsequently integrated to construct a clinical prognostic nomogram intended for preoperative risk estimation.
Evaluation of the nomogram demonstrated strong discriminatory capability across both development and validation populations. Harrell’s concordance index reached 0.805, with a 95 percent confidence interval spanning from 0.713 to 0.896, in the training cohort, and 0.851, with a 95 percent confidence interval of 0.743 to 0.959, in the validation cohort. Time-independent receiver operating characteristic curve analysis further demonstrated consistent predictive performance for disease-free survival over time. In the training cohort, the area under the curve measured 0.782 at two years, 0.764 at three years, and 0.814 at five years. Corresponding area under the curve metrics in the validation cohort were 0.792 at the two-year mark, 0.828 at three years, and 0.824 at five years.
Stratification analysis utilizing the Kaplan-Meier method confirmed that the nomogram successfully categorized patients into significantly differentiated high-risk and low-risk prognostic groups. Based on these observed findings, the authors concluded that routine evaluation of baseline MRI-determined lateral lymph node metastasis, circumferential resection margin involvement, and tumor deposits should be implemented in clinical workflows for MRI-defined T3 rectal cancer to enhance preoperative risk stratification and support personalized treatment planning.
Subject of Research: Baseline MRI prognostic stratification in T3 rectal cancer
Article Title: Baseline MRI-based prognostic stratification in T3 rectal cancer using the DISTANCED structured report
Article References: Que, Y.-T., Wu, X.-H., Wen, Z.-Q., Cai, X.-N., Liu, Y.-Y., Yu, S.-P., Lu, B.-L., & Chen, Y. (2026). Baseline MRI-based prognostic stratification in T3 rectal cancer using the DISTANCED structured report. Cancer Imaging. https://doi.org/10.1186/s40644-026-01120-x
Image Credits: AI Generated
DOI: 10.1186/s40644-026-01120-x
Keywords: rectal cancer, magnetic resonance imaging, prognostic nomogram, disease-free survival, neoadjuvant therapy, circumferential resection margin, tumor deposits, lateral lymph nodes, Baseline, MRI-based, prognostic, stratification
