Costs of breast cancer care by stage and HER-2 Status: a population-based study

Introduction Breast cancer (BC) is one of the most common and leading causes of cancer-related deaths among women. Cost analysis of BC treatment provides essential information for health policy planning, including resource allocation. This study aims to present real-world data on the cost components of BC care, categorized by cancer stage and HER2 status.Methods This retrospective, population-based cohort study examined 1,232 new BC cases diagnosed in 2021 across three Local Health Units in the Italian northeastern Veneto Region. The study calculated per-patient costs for all three years following BC incidence. Care costs were categorized by items and analyzed by cancer stage and HER2 BC status.Results Over a three-year post-diagnosis period, care costs increased from & euro; 25,630 to & euro; 90,924. Total hospitalization costs increased from & euro;6,500 in stage I to & euro;15,488 in stage IV, with a ratio of 2.4. Outpatient costs increased from & euro;11,143 to & euro;25,296, with a ratio of 2.3. In-hospital drug administration rose from & euro;4,427 to & euro;34,210, with a ratio of 7.7. Across all stages, the mean overall cost increased from & euro;27,817 & euro; in HER2-negative patients to & euro;52,193 & euro; in HER2-positive patients, while the breast cancer-specific cost increased from & euro;17,881 & euro; to & euro;36,564 & euro;, respectively. HER2-positive cancers incurred almost twice the cost of HER2-negative BC.Conclusions The overall cost of BC care increases with the stage of cancer at diagnosis, which also affects the allocation of costs among various cost components. In the early stages, expenses mainly relate to surgical and outpatient procedures. For more advanced BC, care costs rise substantially, mainly due to systemic therapies and hospital-based care. The HER status at cancer presentation significantly impacts care costs across all cancer stages.