Whole-Slide ECM Imaging Reveals Dense Fibrous Matrix as a High-Risk Factor for Recurrence in Stage II Colon Cancer

IntroductionThe extracellular matrix (ECM) supports tumor progression by influencing tumor cell migration and invasion. This study examines the link between peritumoral ECM morphology and five-year recurrence risk in TNM Stage II colon cancer, using quantitative whole-slide ECM imaging. We hypothesize that loose ECM regions are associated with increased recurrence risk due to enhanced tumor budding (TB) or poorly differentiated clusters (PDC). MethodsIn a case-control study of 100 TNM Stage II colon cancer patients (25 with recurrence and 75 controls matched by lymph node sampling and tumor extent), Picrosirius red-stained sections were imaged to quantify ten ECM parameters across 798 regions of interest (ROIs). Conditional logistic regression assessed associations between ECM morphologies, TB, PDCs, and recurrence. ResultsUnsupervised clustering identified three ECM morphologies: dense fibrous, loose sparse, and complex tortuous. Dense fibrous ECM correlated strongly with recurrence (aOR 9.43, 95% CI 3.29-29.30, p < 0.001), while loose sparse and complex tortuous ECMs were associated with reduced recurrence risk (aOR 0.33, 95% CI 0.11-0.91, p = 0.040, and aOR 0.14, 95% CI 0.02-0.53, p = 0.012, respectively). TB was highest in loose sparse ECM (mean 9.3), and PDCs were highest in dense fibrous ECM (mean 5.5). DiscussionOur findings suggest that ECM morphology, particularly dense fibrous ECM, predicts recurrence in Stage II colon cancer, highlighting ECM profiling as a promising tool for patient stratification beyond traditional staging.