A new analysis from UC San Francisco argues that diagnostics—medical tests that match patients to the appropriate treatment—are being overlooked both in the United States and around the world. This is slowing progress against major diseases, despite rapid advances in targeted therapies and precision health.

The authors note that nearly half of the world’s population lacks adequate access to diagnostics. These tests receive less investment for research and development, as well as lower insurance reimbursement than drugs, and this is creating barriers to innovation.

“Most people can easily understand how a new drug or surgery might help a patient,” said Kathryn Phillips, Ph.D., a professor of Health Economics in the School of Pharmacy at UC San Francisco and the lead author of the study, which appears in Science. “But the tests that guide medical decisions are just as critical.”

Adjuvant immunotherapy is increasingly integrated into cancer care to reduce recurrence and improve survival. However, its high cost raises critical concerns regarding affordability and economic value across diverse health system contexts.

This review outlines health gains and economic value, and identifies where future research, pricing reform, or prioritization are needed to support evidence-informed policymaking and sustainable use of immunotherapy in cancer treatment pathways.

Question Is adjuvant immunotherapy cost-effective across cancer types?

Findings This systematic review including 69 economic evaluations (2015−2025) found that adjuvant checkpoint inhibitors, usually single-agent, were associated with higher quality-adjusted life-year/life-year gains and were determined to be cost-effective by 40 studies (58%), with the strongest signals in non−small cell lung cancer and melanoma, particularly in early-stage/high-risk populations, and for some combination regimens. Industry-funded studies more frequently reported cost-effective decisions and findings were sensitive to drug prices, model assumptions, and country-specific willingness-to-pay thresholds.

Meaning These findings suggest that adjuvant immunotherapy can offer good value for money in selected high-risk settings; decisions should be indication-specific, aligned with local health technology assessment thresholds, and supported by price negotiation or managed-entry agreements.