Global variations in cancer costing studies: An umbrella review

Despite growing recognition of the financial strain cancer places on households and health systems, evidence on the distribution and drivers of these costs remains fragmented. This umbrella review maps the global literature on cancer costs by category, population, and health system context, and distills the implications for affordability, equity and financial protection.

We conducted an umbrella review of reviews published between January 2008 and December 2023, searching four databases (MEDLINE, Scopus, Web of Science, and Cochrane Library) using a pre-registered protocol (PROSPERO #CRD42023422566) and complemented by a narrative synthesis. Reviews that reported as a primary outcome direct or indirect costs or measured the burden of cancer costs were eligible for inclusion. The unit of analysis was review study.

We included 198 reviews covering 5784 studies, capturing individual and system-wide costs. Evidence was concentrated in high-income countries, with low-income regions, particularly Africa, underrepresented. The societal perspective was most common. Reviews largely focused on adults (87%), with only 2% on childhood cancers. Within the reviews, costing studies most frequently assessed breast (30%), colorectal (26%), lung (23%), and prostate (21%) cancers. Most reviews focused on the initial treatment phase (79%), while only 8% reported costs across the full cancer continuum from prevention to end of life. Reviews primarily captured direct medical costs (e.g., surgery, drugs, hospitalizations) and, when adopting a societal perspective, indirect costs from productivity losses and, less often, caregiver burden. Where measured (17%), cost burden was characterized as financial toxicity (50%) and catastrophic health expenditure (59%), mainly in low- and middle-income countries (LMICs).

Our review exposes major gaps in how cancer affordability is understood and measured worldwide. Evidence is concentrated in high-income countries and narrowly focused on treatment costs, masking the full financial burden of cancer. Advancing equity and financial protection will require coordinated action to prevent catastrophic spending, care exclusion, and rising out-of-pocket costs.