Do not buy whole-body PET-CT or tumor-marker screening packages when you have no symptoms
More testing does not automatically mean fewer cancer deaths. Screening people without symptoms can find abnormalities that are harmless, while setting off expensive and sometimes harmful investigations. Use screening tests with demonstrated benefit for your age and risk.
What it takes
A whole-body PET-CT in China costs about RMB 7,000–10,000 and involves radiation. Tumor-marker packages cost several hundred RMB. A false positive is an apparent abnormality that turns out to be a false alarm. The main downstream cost can be further tests, biopsies, or unnecessary surgery, with both expense and physical suffering.
What you may gain
The USPSTF gives ovarian-cancer screening with CA-125 or ultrasound a D recommendation. In PLCO, ovarian-cancer mortality was 0.34% versus 0.29%, RR 1.18 (95% CI 0.82–1.71), with no demonstrated benefit. Across trials, false-positive results led to unnecessary surgery in 0.2%–3.25% of participants; up to 15% of those operated on had serious complications. In an observational study of whole-body CT in 1,192 people without symptoms, 86% had at least one finding and 37% were advised to undergo further assessment. Most findings were benign. “Scan everything and catch cancer early” sounds reassuring, but findings alone are not evidence of better outcomes.
Context & considerations
The randomized evidence concerns the tumor-marker screening example. Evidence on whole-body CT and PET-CT screening is largely observational and would separately receive grade B. Screening with established benefits—including colorectal, cervical, and breast screening, and low-dose chest CT for appropriate high-risk people—is covered in chapter 1. Imaging for symptoms or a known cancer is diagnosis or disease management, a different situation.
Research & references
US Preventive Services Task Force (2018). Screening for Ovarian Cancer. JAMA. https://doi.org/10.1001/jama.2017.21926; USPSTF, Ovarian Cancer: Screening. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/ovarian-cancer-screening; Furtado CD et al. (2005). Whole-body CT screening: spectrum of findings and recommendations in 1192 patients. Radiology. https://doi.org/10.1148/radiol.2372041741.