Diagnostic Costs of Metastatic and Unknown Primary Cancers in Alberta, Canada, 2017–2021

Given the aggressive symptomatic nature of Cancer of Unknown Primary (CUP) and non-standardized diagnostic approaches, it is expected that the cost of CUP diagnosis is higher than other cancers. This study aims to investigate the diagnostic costs of CUP as compared to other types of metastatic cancer and non-metastatic cancers over a 5-year period in the provincial health authority of Alberta, Canada. Health service utilization (inpatient, outpatient, physician services) and associated costs were compared in the 6-months prior to the diagnostic date, to the baseline period for CUP and non-CUP patients. Costs were estimated using claims amounts paid to physicians and by multiplying the resource intensity weight with the cost per standard hospital stay in Alberta. Diagnostics for CUP cost $9005 per-patient, which were 1.8x more costly than other metastatic cancers ($5027). These higher costs were driven by a large proportion of patients being diagnosed in hospital. Our findings revealed that the per-patient cost of a CUP hospital diagnosis ($13,925) was 10x that of a CUP community diagnosis ($1225) and community diagnosis of a stage IV cancer ($1426). Potential benefits exist in streamlining efforts to diagnose early, improve patient health outcomes, and reduce overall system costs of diagnosing CUP.