Saturday , July 31 2021

Screening for lung cancer is a controversial idea

IT Can start with something as trivial as a small cough that will not disappear. But often lung cancer does not cause any symptoms until it is too late. Ask Graham Thomas, who in 2014 found that hiding behind pneumonia was lung cancer at stage IV of his development. Stage IV is a medical jargon for a tumor that has spread to other parts of the body. There is no stage V.

Mr. Thomas has already spoken as part of a campaign of the Roy Castle Foundation's Lung Cancer Foundation, a charity for raising awareness of the disease in the UK. He starts smoking at the age of 14 and says that people think he has brought his illness to himself and that cancer is least deserving of sympathy. But he claims that maybe it should not be because he kills cancer most.

One of the causes of lung cancer is so fatal that at the time of diagnosis, three-quarters of people, like Mr Thomas, have already arrived at stage IV. In Europe, five-year survival after diagnosis is about 13%, with small differences between countries. Early detection of tumors would allow them to be treated before they spread – improving outcomes and reducing medical bills. Yet many places that happily invite people to participate in screening programs designed to detect breast, gut, prostate, and cervical cancer have opposed the expansion of the idea to lung cancer.

Screening Screening

The question is whether such screening will do more than damage. The history of screening shows that the answer is not obvious. In 1985, for example, Japan launched a mass screening program for neuroblastoma, a rare tumor of the child's nervous system. The program revealed 337 such tumors over the first three years, but two decades later there is no evidence that it has reduced the number of children who die. The efforts were mostly selected slowly growing tumors, which hardly had any harmful results. But the discovery of these tumors has caused very unnecessary treatment.

Screening of prostate cancer is also affected. This test often raises concerns about a possible cancer that appears to be not there (false positively). However, this finding involves tests such as biopsies that are invasive, painful and can cause infection. If a group of men aged 55 to 69 are checked regularly for more than a decade, 12% will experience such a false positively and may be subject to unnecessary biopsy. Conversely, screening for prostate cancer misses 15% of men who actually have cancer (false negative).

Moreover, even when prostate screening is correct, by detecting a tumor that is actually there, the tumor is often one that would not shorten the patient's life because he would die for other reasons before the tumor kills him (overweight diagnosis). However, all men who study suggest they are being treated with cancer, and many people take it, risking side effects such as incontinence and impotence. According to Bob Steele, a professor at the University of Dundee, who is chairman of the Great Britain National Screening Commission, "You must treat 30 men to save a person from death."

The first evidence that lung cancer screening may be helpful despite these concerns comes from a US study called the National Pulmonary Screening StudyNLST), which took place between 2002 and 2009. NLST about 53,000 people aged between 55 and 74, who have had a smoking history of 30 years and over (one pack per year is the equivalent of one packet of cigarettes a day for one year). Standard chest x-rays against low-dose computed tomography (CT) – improved xray-based technique. The participants were examined once a year for three years, and appropriate treatment was offered to those whose scan suggests the presence of tumors. At the end of the process those who have been CT-Scorers are 20% less likely than those who were x– invented to have died of lung cancer. This is equivalent to three less deaths per 1,000 screening, and a 7% mortality rate for all causes.

Mostly, NLST established CT scan as a route. As Hilary Robbins of the World Health Organization's International Agency for Research on Cancer, noted that the process still raises concerns about false positive results, as it puts 356 people to 1,000 in need of follow-up action. But improvements in the protocol used, which now neglects the smallest anomalies because they are rarely cancerous, have come true in half (see the chart) – and the number of people suffering from complications has also fallen.

The latest process, NELSON, was held in Europe. It took ten years and four years of scans were included. Although not yet officially published, its main findings were announced last year and were extremely encouraging.

Two-thirds of the cancers found in the experimental branch of the study are in Stage I or II of their growth and are thus extremely treatable. In the control group of the study, in contrast, two thirds were in Stage III or IV. Furthermore, NELSON there was a more nuanced approach to the issue of false positive results. If something potentially ominous is observed, the protocol used is to order a quarterly tracking. Only if the growth has expanded in the interim period is considered likely to be cancer and treated accordingly. Screening, Researchers NELSON It was found to reduce mortality by 26% for men and 61% for women in the course of the study.

Such evidence has convinced some (though not all) that screening for lung cancer is useful in some circumstances. And in one part of the world, this belief turns into action. Now there are plans for more than half a million people in England who are current or former smokers to be offered over the next four years to have a health check on the lungs at a local clinic. This is after a pilot project in Manchester that examined 2541 people and found 61 lung cancer patients – 80% of whom were at an early stage.

Of course, the question of spending, which, according to some, is too high. Economists measure the efficacy of medical technology with how much health is earned on money spent. The unit of profit for health is QALY (a quality life year that attempts to factor in patient experience as well as increased life expectancy). By this measure the study in Manchester was extremely effective. It costs £ 10,069 (about $ 13,000) in number QALYone third of the amount determined by the. T NHS as a maximum for one procedure to be considered as profitable.

Although some skeptics still claim that the money spent on screening will be better deployed, trying to stop smoking people – or, better yet, prevent them from starting first – the case of screening smokers for lung cancer now look good. There are, however, wrinkles. Focusing the screening on smokers will surely achieve the best results. But this will exclude any one of the five suffering from the disease who have never touched a cigarette in their lives. To be cost-effective, screening should focus on those like Mr Thomas, who are deliberately put in danger. All others will be excluded from the process. What irony.

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