Early pilot feasibility report on deep longitudinal profiling in metastatic cancer patients

PURPOSEA substantial proportion of patients receiving genomically matched therapies do not achieve clinical benefit, underscoring the influence of non-genetic factors such as microbiome composition, metabolic state, physiological parameters, and lifestyle behaviors on cancer outcomes. High-Definition Oncology (HDO) proposes integrating longitudinal, multi-modal patient data--spanning clinical, molecular, physiological, and behavioral domains--to enable truly individualized cancer care. The present manuscript describes the design, methodological framework, and initial feasibility results of the HDO study, which aims to evaluate the feasibility of harmonized, deep longitudinal profiling across clinical, molecular, physiological, and behavioral domains in women with metastatic cancer. PATIENTS AND METHODSWe initiated a prospective, multicenter observational study (HDO study; NCT06590506) enrolling 300 female patients with newly diagnosed metastatic breast, lung, or colorectal cancer. Here, we report the study design, standardized workflows, prespecified feasibility criteria, and early internal pilot results. Eleven data modalities are collected longitudinally, including tumor and germline genomics, germline epigenomics, gut microbiome, blood and stool metabolomics and proteomics, exposome characterization, wearable-derived physiological monitoring, digital footprint assessment, medical imaging, and patient-reported outcomes. Standardized workflows govern clinical procedures, data acquisition, biospecimen processing, and quality control across all participating sites. RESULTSFeasibility was evaluated in the first 30 participants (10% of planned accrual). Patients completed 100% of scheduled clinical visits, 97.4% of planned plasma collections, 80.7% of stool samples, and all tumor biopsies. Wearable devices captured activity, heart rate, sleep, and blood oxygen saturation data during 95.0%, 84.2%, 90.6%, and 70.7% of total patient-days, respectively. Biospecimens met predefined quality control metrics across all molecular modalities. Engagement with mobile applications for pain and emotion reporting exceeded 80%. CONCLUSIONThe HDO study demonstrates the feasibility of comprehensive, longitudinal, multi-modal data collection in women with metastatic cancer. This protocol establishes an integrated framework for future analyses aimed at characterizing disease trajectories, defining molecular and physiological determinants of outcomes, and developing patient-specific computational models.