Healthcare resource use (HCRU) intensity prior to cancer diagnosis and real-world outcomes in early-stage cancers.

1644 Background: Choosing Wisely initiatives aim to reduce futile care by emphasizing the role of clinicians in healthcare decision-making. However, HCRU is strongly shaped by patient preferences with some inherently favoring high-intensity (“maximalist”) care and others preferring low-intensity (“minimalist”) approaches. We hypothesized that HCRU in the years before an early-stage cancer diagnosis may, in part, represent the healthcare seeking preferences of patients rather than strictly reflecting their clinical needs. Methods: We conducted a population-based retrospective cohort study of adults diagnosed with stage I-II breast, lung or colon cancer from 2015 to 2020 in Alberta, Canada with follow-up to 2025. Pre-diagnosis HCRU was quantified using ambulatory, emergency, and inpatient encounters. Patients were categorized as high (≥75th percentile) or low (≤25th percentile) users; intermediate users were excluded. Cohorts of high vs. low users were matched based on age, sex, rurality, stage and Charlson Comorbidity Index (CCI) and stratified by tumor site. Outcomes included cancer-specific survival (CSS), overall survival (OS) and post-diagnosis HCRU. Results: The matched cohort included 7,384 patients (64% breast, 21% lung, 15% colon) with balance across all covariates. Median age was 67 years, 68% had stage I disease and 95% had CCI<2. For all cancer sites, CSS did not differ between high and low users (see Table). High pre-diagnosis HCRU was associated with worse OS in breast (HR 1.34, p<0.001) and colon cancer (HR 1.36, p=0.003), but not in lung cancer (HR 1.02, p=0.76). Importantly, HCRU patterns pre-diagnosis strongly persisted post-diagnosis, with high users continuing to consume significantly more healthcare resources than low users for 4 years after cancer diagnosis (p<0.001). Conclusions: In this relatively healthy cohort of early-stage, highly curable cancers, greater pre-diagnosis HCRU was associated with sustained post-diagnosis HCRU intensity without any significant differences in cancer-specific outcomes. Our findings suggest that utilization patterns may reflect patient-level behaviors as much as clinical necessity, thus contributing to volume-driven care that may have limited clinical value. Advancing future Choosing Wisely initiatives in oncology must extend beyond clinician stewardship to address patient expectations about their healthcare interactions. This strategy would better align with value-based care and promote health system sustainability. CSS based on pre-diagnosis HCRU. Cancer site Pre-diagnosis HCRU 10-year CSS (95% CI) HR for CSS (95% CI) P value Breast Low 89% (87%, 92%) Reference 0.55 Breast High 91% (90%, 93%) 0.93 (0.74,1.18) Lung Low 63% (58%, 69%) Reference 0.72 Lung High 68% (64%, 72%) 1.04 (0.85,1.26) Colon Low 90% (87%, 93%) Reference 0.39 Colon High 92% (89%, 95%) 0.82 (0.52,1.29)