The RaP-DMac-LiMe study (Radiogenomic Profiling of Dendritic Cells and Macrophages to Predict Recurrence in Colorectal Liver Metastasis) is a monocentric, non-profit observational study promoted by Fondazione Policlinico Universitario A. Gemelli IRCCS. Its primary aim is to identify immunological, genomic, and radiomic biomarkers associated with recurrence risk in patients with colorectal liver metastases (CRLM) undergoing curative-intent liver resection.

The study is based on the need to improve prognostic stratification in CRLM by integrating information from the tumor immune microenvironment, tumor genomics, radiomics, and clinical data. Particular attention is given to myeloid immune cells, especially dendritic cells and tumor-associated macrophages, whose role in metastatic progression and recurrence remains insufficiently understood.

The primary objective is to assess the association between myeloid immune profiles and recurrence risk through integrated molecular, spatial, genomic, and radiological analyses. Secondary objectives include characterizing the transcriptomic and genomic features of dendritic cells and macrophages, identifying radiomic and circulating tumor DNA (ctDNA) biomarkers, and evaluating their potential as non-invasive tools for recurrence prediction and patient stratification.

The study includes a retrospective cohort of approximately 160 patients treated between 2009 and 2023 and a prospective cohort of approximately 50 patients who will be followed for 24 months. Tumor tissue samples, peripheral blood, imaging data (CT/MRI), and clinical information collected during routine care will be analyzed without introducing any experimental interventions or deviations from standard clinical practice.

Analyses will include transcriptomic profiling, multiplex spatial characterization of immune cells, circulating tumor DNA sequencing using next-generation sequencing technologies, radiomic feature extraction, and integration of all data using statistical and machine learning approaches. Predictive models will be trained on retrospective data and independently validated in the prospective cohort.

The primary endpoint is the prediction of colorectal liver metastasis recurrence within two years after liver resection. Ultimately, the study aims to develop and validate a multimodal predictive model integrating immune, genomic, radiomic, and clinical variables to improve recurrence risk assessment and support personalized patient management.

The overall study duration is 36 months. All procedures will be conducted in accordance with ethical standards and data protection regulations, with samples and clinical data pseudonymized and handled in compliance with the GDPR.