Methylation Profile Test (Methylscape) in Body Fluids for Multi-Cancer Detection and Monitoring in Colombia

Inclusion Criteria: * Adults aged 18 years or older. * Willing and able to participate and to provide the required samples (blood, urine, saliva) and demographic information (age, sex, race/ethnicity, BMI). * Able to provide written informed consent for participation and for use of biological samples. For CTIC Biobank samples, prior research-use consent is verified. * Demographic/anthropometric comparability (race, ethnicity, BMI) with other participants; race/ethnicity by self-identification (WHO and national census categories); BMI per WHO categories. Inclusion - Cancer cohort: * Cancer diagnosis confirmed within 90 days prior to sample collection. * Biopsy-proven malignancy with radiological staging. * No anticancer treatment at the time of collection or within the previous 3 years. * Inclusion - Cancer-free (healthy) cohort: * No cancer diagnosis or treatment in the previous 3 years (ICD-O-3 behavior code 2 or 3). * Not under evaluation for suspected cancer (verified by medical record review or additional medical evaluation). * Subjects with benign tumors (code 0) or tumors of uncertain behavior (code 1) may be included if there is no clinical evidence of progression or malignancy. Additional criteria - tumor-burden monitoring (Sub-study 2b): * Biopsy-confirmed cancer. * ECOG performance status ≤ 2. Exclusion Criteria (both cohorts): * Failure to meet the general or cohort-specific inclusion criteria. * Pregnancy. * Organ transplant recipients. * Use of demethylating agents (azacitidine, decitabine) or cytotoxic agents (including for autoimmune/inflammatory conditions). * Prior or ongoing anticancer therapy: cancer surgery beyond that needed for diagnosis; local, regional, or systemic chemotherapy (including chemoembolization); targeted therapy; immunotherapy (including cancer vaccines); hormonal therapy; or radiotherapy.