United States: It has been confirmed by many studies that lung cancer screening done annually using a CT scan does save lives. However, the new data revealed that scans pick up abnormalities too often, which leads to further follow-up invasive tests and causes more complications.
The researchers said that no one is saying that all smokers and ex-smokers should skip lung CT scans; however, “real-world” complication levels after screening could be higher than physicians once assumed, US News reported.
The findings are published in the Annals of Internal Medicine journal on January 2.
Doctors need to prioritize screening test
Katharine Rendle, assistant professor at the University of Pennsylvania’s Perelman School of Medicine in Philadelphia and the lead researcher in the study, said doctors need to prioritize screening for those patients who are “most likely to receive a net benefit from screening in relation to potential complications and other harms.”
Present Cancer and screening tests stats
According to the American Cancer Society, with more than 127,000 deaths in 2023, lung cancer has remained the number one cancer killer.
Although the early detection of Cancer can save lives, the US Preventive Services Task Force (an independent panel of experts) suggested annual lung cancer screening for all adults ages 50 to 80 who have a smoking history of 20 pack-years, which means they smoked at least 20 cigarettes a day for 20 years or more.
As per a recent study, around 81 percent of people with tumors who had gone through an annual CT screening were still alive 20 years later.
However, as in all screening tests, false-positive results (where something that looks like lung cancer turns out to be non-threatening) could happen, which leads to unnecessary follow-up tests, US News reported.
What did the study find?
In the large trial that triggered the new screening guidelines, these downstream tests and associated complications were relatively low.
Rendle’s team in order to see if that was still true because screening has become more widespread and moved to a “real-world” setting.
The new study tracked outcomes for around 9,300 US patients screened for lung cancer at five major healthcare systems between 2014 and 2018.
It was found that just under 16 percent of the patients had some type of “abnormality” show up on their CT scans. 140 out of these 1,492 patients were diagnosed with lung cancer over the following year, US News reported.
About a third (31.9 percent) of patients who underwent CT screening received some kind of follow-up scan, while a much smaller number (2.8 percent) had to undergo a lung biopsy or other invasive test. Among the latter group, only a third (30.6 percent) had some form of complication because of the procedure, which is anything from transient respiratory issues to cardiac arrest or a collapsed lung.
As noted by Rendle’s team, this complication rate is much more than the 17.7 percent rate seen in the National Lung Screening Trial (NLST), which prompted current lung cancer screening recommendations.
Reasons for difference
According to Rendle’s team, “real-world” patients are often sicker than those who were selected for the NLST who were “older, were more likely to be currently smoking and had a higher rate of co-morbid conditions [other illnesses].”
This puts a person at higher risk for a complication following any invasive test, Rendle’s team suggested, US News reported.
The researchers said that overall, “We observed higher rates of both invasive procedures and complications in patients screened for lung cancer” compared to what was observed in the NLST.
Rendle’s team further noted that this is “a difference that could shift the balance of screening harms and benefits in community practice.
They said Smokers and ex-smokers might want to have more detailed discussions with their doctors, weighing the pros and cons of annual CT screening for their particular case, according to the US News report.