"CT scanning became widespread in the 1980's. Cancer incidence is flat to slightly decreased since then. I'm not sure their risk model matches reality. Many of these models are based on extrapolation from higher radiation exposures and there may be a fundamental issue with how they estimate risk."
<a href="https://x.com/NathanRuch/status/1911803050857050502" rel="nofollow">https://x.com/NathanRuch/status/1911803050857050502</a><p>From the paper itself:
"We projected future lifetime radiation-induced cancer risk
using the National Cancer Institute’s Radiation Risk Assessment Tool (RadRAT) software version 4.3.1, which utilizes risk models from the National Academy of Sciences’
Biologic Effects of Ionizing Radiation (BEIR) VII report for 11 site-specific cancers ... using a more recent follow-up of the Japanese atomic bomb survivors and pooled analyses of other medically exposed cohorts."<p>So I wouldn't hang my hat on the claim "that CT examinations in 2023 were projected to result in approximately 103,000 future cancers over the course of the lifetime of exposed patients."<p>Are CTs without risk? Of course not but quantifying that risk isn't easy with the data and models we have available. We should be glad that the authors are trying to do so but also be cautious about publicizing their estimate as an eye-catching headline. Since most who read the headline will over interpret it as an established scientific fact that meets a higher level of evidence than has actually been met.
If you ever do get a CT scan I highly recommend requesting the DICOM images from the hospital. The open source Invesalius program can do some nice volumetric renders and you can see things your doctor probably isn't going to take the time to bother with showing you.
I found this interesting:<p>> In the UK, regulations mean that CT scan requests are reviewed by radiologists and only carried out when clinically justified and with optimised doses. Because of this, the UK has one of the lowest rates of CT scans per population in OECD countries – less than 100 scans per 1,000 people, compared with over 250 scans per 1,000 people in the US. Research studies have provided evidence that CT scans used in targeted screening on healthy people, such as for lung cancer, will save lives, and that the benefits outweigh the risks.<p>> However, the researchers argue that the risk of cancer outweighs any potential benefit from the whole-body scans offered by private clinics to healthy people.<p>So the authors do agree that "targeted screening of healthy people" done right is beneficial even though CT scans are seen as a risk-inducing measure, yet this isn't true if you just go and sell whole-body scans to healthy people, which tells me that "CT scan" may not be precise enough a word to know what the risk-benefit ratio might be in a given case; you'd have to at least add what body part was scanned, why, and maybe even where: if an American tells you they got a CT scan chances are apparently higher they just got sold an expensive and risk-inducing full-body shotgun diagnosis with little chance of turning up anything while when a Brit tells you the same, chances are higher that an experienced person tasked with saying no when in doubt vetted risks and benefits and concluded a focused exposure was worth it.