Aggressive cancer screening programs that detect indolent tumors do not lead to a reduction in population-level all-cause or cancer-specific mortality rates.

Study: Mortality impact, risks, and benefits of general population screening for ovarian cancer: the UKCTOCS randomised controlled trial.

Doctors tested if yearly blood tests and ultrasounds could save more lives from ovarian cancer, but even though they found more early cancers, the number of deaths didn’t go down — meaning finding these slow-growing tumors didn’t help people live longer.

Study: Overdiagnosis in low-dose computed tomography screening for lung cancer.

This study found that nearly 1 in 5 lung cancers found by CT scans are harmless and would never hurt the person — but they still get treated, causing stress and side effects. Since these fake threats don’t save lives, the screening doesn’t really lower death rates overall.

Study: Association between screening and the thyroid cancer “epidemic” in South Korea: evidence from a nationwide study

South Korea started screening lots of healthy people for thyroid cancer with ultrasounds, and found way more tiny cancers — but people didn’t start dying less. That means they were finding cancers that never would’ve hurt anyone, proving that screening too much doesn’t save lives.

Study: Korea's thyroid-cancer "epidemic"--screening and overdiagnosis.

Korea started screening for thyroid cancer a lot, and found way more cases — but people didn’t start dying less. That means many of those 'cancers' were harmless and didn’t need to be found or treated.