‘Low-dose CT screening best for high-risk patients’
In the European Union, lung cancer is the 4th cancer in incidence with 313,000 new cases per year, but remains the number one killer, accounting to 268,000 deaths per year. Lung cancer represents 21% of all cancer deaths in the EU thereby killing more people each year than breast, prostate, colorectal and pancreatic cancer combined. Prof Mathias Goyen, Chief Medical Officer Oncology, GE Healthcare, explains how low-dose CT screening can change this situation
The overall five-year survival rate for lung cancer is among the lowest (17%) of all types of cancer but is significantly higher when the cancer is diagnosed at an early stage (54%). However, currently only 15% of lung cancer cases are diagnosed at such an early stage.(2)
Researchers have continued to seek an effective lung cancer screening tool that might decrease mortality in the way that other commonly accepted screening practices have done for their respective diseases. Early detection with low dose CT can improve prognosis and treatment and reduce mortality rates for patients with a high risk of lung cancer.
The landmark National Lung Screening Trial (NLST) was conducted at 33 medical institutions with over 53,000 older, otherwise healthy patients at high-risk due to smoking history. Half of the participants were screened using low dose CT (LDCT), the other half were screened using chest X-ray. The trial demonstrated that the use of low dose CT screening decisively reduced the mortality rate from lung cancer by 20 percent compared to use of chest X-ray. The NLST also revealed a significant 6.7% reduction in the rate of death from any cause using low dose CT screening. (3)
The Dutch-Belgian Randomised Lung Cancer Screening Trial (Dutch acronym: NELSON study) was designed to investigate whether screening for lung cancer by low-dose multi-detector computed tomography (CT) in high-risk subjects will lead to a decrease in 10-year lung cancer mortality of at least 25% compared with a control group without screening. Since the start of the NELSON study in 2003, 7155 screened participants were followed up for a median of 8.16 years, during which time 187 (3%) patients were diagnosed with 196 screen-detected cancers. In addition, 34 (<1%) patients were diagnosed with a further 35 interval lung cancers, including 19 patients in the year after screening and 15 patients in the second year after CT. When the results of the first three screening rounds were pooled with a 2-year-follow-up, CT screening was 84.6% sensitive and 98.6% specific for lung cancer detection, with positive and negative predictive values of 40.4% and 99.8%, respectively. (4)
Considerations in screening
The challenge with any screening tool is finding a balance between false-negative and false-positive results. False-negative results cause false security in the patient and delay diagnosis of disease that is actually present. False-positive results cause increased anxiety for the patient, as well as increased healthcare costs and exposure to potential risks with further diagnostic procedures. An inverse relationship often exists between false negatives and false positives; a tool sensitive enough to reduce false negatives will increase false positive results.
Many questions surround the concept of LDCT screening for lung cancer. Who should be screened, how frequently, how much will it cost, and how will repeated exposure to LDCT radiation affect patients?
GE Healthcare first to receive FDA clearance for Low Dose CT Lung Cancer screening
GE Healthcare is the first company with a low dose computed tomography (CT) lung cancer screening option that is cleared by the U.S. FDA for lung cancer screening. Both the U.S. Preventative Services Task Force (USPSTF) and the Centers for Medicare and Medicaid Services (CMS) recommend the use of low dose CT lung cancer screening for high-risk individuals. Additionally, Medicare has approved insurance reimbursement for its beneficiaries who are eligible for the use of low dose CT lung cancer screening in high-risk patients. Early detection from an annual lung cancer screening with low dose CT in high-risk persons can prevent a substantial number of lung cancer–related deaths. Physicians using low dose CT for lung cancer screening will now have access to the benefits from a screening indication, including GE Healthcare’s new low-dose screening reference protocols. These new protocols are tailored to the CT system, patient size, and the most current recommendations from a wide range of professional medical and governmental organizations.
Now, qualified GE Healthcare CT scanners can be confidently used by physicians within their FDA cleared indications for use, delivering low dose, short scan times, and clear and sharp images for the detection of small lung nodules. These nodules are critical in identifying lung cancer at its earliest stages when it is the most treatable and curable.
1. The World Health Organisation
2. American Cancer Society. Cancer Facts and Figures 2015.
3. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med. 2011;365(5):395-409.
4. Detection of lung cancer through low-dose CT screening (NELSON): a prespecified analysis of screening test performance and interval cancers. Lancet Oncol. 2014 Nov;15(12):1342-50