Clinical Research Directory

Inclusion Criteria: * Histologically confirmed diagnosis of metastatic (Stage IV) adenocarcinoma of the colon or rectum. * Received at least one cycle of anti-EGFR therapy (cetuximab or panitumumab), either as monotherapy or in combination regimens, regardless of the line of therapy. * Anti-EGFR therapy administered between January 2016 and December 2022. * Availability of formalin-fixed paraffin-embedded (FFPE) tumor tissue blocks (from primary tumor or metastatic site) stored in the institutional biobank, with adequate quality for molecular analysis Exclusion Criteria: * Primary tumor originating in sites other than the colon or rectum. * Presence of activating mutations in KRAS or NRAS genes. * Presence of BRAF gene mutation (except for patients who received anti-EGFR therapy combined with BRAF inhibitors, according to standard clinical practice for this subgroup). * Tumor histology other than adenocarcinoma. * Insufficient clinical or follow-up data in medical records for the evaluation of the study's primary endpoints