Introduction
The strategic implementation of cancer screening facilitates early cancer detection, thereby improving patient survival through less invasive treatment options []. National guidelines, such as those developed by the US Preventive Services Task Force and the Japan National Cancer Center, clearly define the populations that benefit from screening and the tests recommended for them, based on robust evidence of mortality reduction [,]. Despite these guidelines, many individuals still undergo nonrecommended screenings, including breast cancer screening in people younger than the recommended age and whole-body positron emission tomography-computed tomography (PET-CT) imaging [,].
These non–guideline-based screenings often cause harm to participants through false-positive results, overdiagnosis, and…