Personalized colorectal cancer risk assessment through explainable AI and Gut microbiome profiling.

Journal: Gut microbes
Published Date:

Abstract

The clinical adenoma - carcinoma progression represents a well-established framework for understanding colorectal cancer (CRC) development, although the molecular mechanisms underlying this transition remain only partially understood. Increasing evidence suggests the gut microbiome (GM) as a key modulator of colorectal carcinogenesis, positioning microbial profiling as a promising avenue for noninvasive risk stratification and early detection. In this study, Machine Learning (ML) classifiers integrated with eXplainable Artificial Intelligence (XAI) techniques were employed to identify microbiome-derived biomarkers predictive of CRC and adenomatous lesions. The models were trained on 16S rRNA sequencing data from 453 patients and evaluated through cross-validation, achieving AU-ROC and AU-PRC scores of 0.71 and 0.67, respectively. External validation on an independent Italian cohort () yielded AU-ROC and AU-PRC scores of 0.70 and 0.89, respectively. XAI-based interpretation revealed consistent microbial signatures across datasets. In detail, taxa belonging to the and genera were associated with increased CRC risk, whereas the group was identified as a robust negative predictor. Beyond classification, patient-level explanations enabled by XAI facilitated the identification of adenoma subgroups exhibiting microbiome profiles converging toward those of CRC, suggesting the presence of transitional microbial states. Moreover, SHAP-based interaction networks uncovered microbial hubs and inter-species dependencies characterizing high-risk configurations, providing insights into the ecological dynamics of colorectal tumorigenesis. These findings demonstrate the added XAI value in elucidating microbiome interactions, enhancing model interpretability, and supporting biologically informed hypotheses. This integrative, explainable framework highlights the potential of AI-driven microbiome analysis in precision oncology and advances the development of interpretable, noninvasive tools for CRC risk prediction and management.

Authors

  • Pierfrancesco Novielli
    Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti Universita' degli Studi di Bari Aldo Moro, Bari, Italy.
  • Simone Baldi
    Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
  • Donato Romano
    The BioRobotics Institute, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggio 34, 56025 Pontedera, Pisa, Italy. donato.romano@santannapisa.it.
  • Michele Magarelli
    Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi di Bari Aldo Moro, Bari, 70125, Italy.
  • Domenico Diacono
    Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari, Italy. Electronic address: domenico.diacono@ba.infn.it.
  • Pierpaolo Di Bitonto
    Department of Soil, Plant and Food Science, University of Bari Aldo Moro, Bari, Italy.
  • Giulia Nannini
    Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
  • Leandro Di Gloria
    Department of Biomedical, Experimental and Clinical Sciences "Mario Serio", University of Florence, Florence, Italy.
  • Roberto Bellotti
    Dipartimento Interateneo di Fisica "M. Merlin", Università degli studi di Bari "A. Moro", Bari, Italy; Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari, Italy. Electronic address: roberto.bellotti@uniba.it.
  • Amedeo Amedei
    Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy; Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Florence, Italy. Electronic address: amedeo.amedei@unifi.i.
  • Sabina Tangaro
    Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari, Italy. Electronic address: Sonia.Tangaro@ba.infn.it.