overdiagnosis
Detection of cancers through screening that would never have caused symptoms or death during a person's lifetime.
Full Definition
Overdiagnosis occurs when screening detects cancers that, while histologically genuine, would never have progressed to cause symptoms, illness, or death during the patient's natural lifetime. This phenomenon represents a significant challenge in cancer screening programs, as it can lead to unnecessary treatment, psychological distress, and healthcare costs without providing survival benefit. Overdiagnosis is particularly concerning in cancers that may grow very slowly or remain dormant, such as some prostate cancers detected through PSA screening or ductal carcinoma in situ found through mammography. The concept is distinct from false positives, as overdiagnosed cancers are real cancers that simply would not have become clinically relevant.
Usage
Usage note: Distinct from false positives (not cancer) and overtreatment (excessive therapy). Overdiagnosis refers specifically to real but clinically irrelevant cancers.
In Context
- "Prostate cancer screening programs must balance early detection benefits against overdiagnosis risks." — Health policy analysis
- "The estimated overdiagnosis rate for mammographic screening ranges from 10-30% of detected cancers." — Epidemiological study