Screening for cancer: the economic, medical, and psychosocial issues.

Despite significant improvements in mortality over the past 20 years, cancer remains the second leading cause of death in the United States. One reason for the improvement in mortality is screening for several common cancers in people at average risk for breast, cervical, colorectal, and prostate cancers, and screening for lung cancer in those with a 20-plus pack-year history. Such screening may result in earlier diagnosis when the cancer is most likely to respond to treatment. However, there are no population-based screening recommendations for the majority of cancers in average-risk patients, most of which are not diagnosed until the later stages. One question is whether earlier diagnosis could not only reduce mortality rates but also reduce medical costs. Screening comes with several potential risks, including false positives and overdiagnosis, both of which can affect patients' mental health, increase morbidity and mortality, and lead to excess spending. Additionally, certain cancers can evade traditional screening tests and lead to false-negative results, which delays cancer detection, treatment, and may affect treatment efficacy. The advent of liquid biopsy tests that could screen for dozens of cancers holds promise for identifying more cancers early. However, the cost, the potential for overdiagnosis and false positives, and a lack of evidence demonstrating clinical utility or an improvement in health outcomes call into question their potential use for widespread screening. Government and managed care organizations will need to consider the risks and benefits of these assays in determining coverage.