Level II Services: Preventive services for which clinicians and care systems should assess the need. These services should be recommended to each patient as they have value, but less than those in Level I.
|The USPSTF recommendation is endorsed by the ICSI Preventive Services work group with qualifications.
||Grade of Recommendation and Level of Certainty as Evaluated by USPSTF|
||Grade of Recommendation:
Level of Certainty:
Although lung cancer screening is not an alternative to smoking cessation, the USPSTF found adequate evidence that annual screening for lung cancer with LDCT in a defined population of high-risk persons can prevent a substantial number of lung cancer-related deaths. Direct evidence from a large, well-conducted, randomized, controlled trial (RCT) provides moderate certainty of the benefit of lung cancer screening with LDCT in this population. The magnitude of benefit to the person depends on that person's risk for lung cancer because those who are at highest risk are most likely to benefit. Screening cannot prevent most lung cancer-related deaths, and smoking cessation remains essential.
The harms associated with LDCT screening include death, false-negative and false-positive results, incidental findings, over-diagnosis and radiation exposure. False-positive LDCT results occur in a substantial proportion of screened persons; 95% of all positive results do not lead to a diagnosis of cancer. In a high-quality screening program, further imaging can resolve most false-positive results; however, some patients may require invasive procedures.
The USPSTF found insufficient evidence on the harms associated with incidental findings. Over-diagnosis of lung cancer occurs, but its precise magnitude is uncertain. A modeling study performed for the USPSTF estimated that 10 to 12% of screen-detected cancer cases are over-diagnosed – that is, they would not have been detected in the patient's lifetime without screening. Radiation harms, including cancer resulting from cumulative exposure to radiation, vary depending on the age at the start of screening; the number of scans received; and the person's exposure to other sources of radiation, particularly other medical imaging.
The USPSTF concludes with moderate certainty that annual screening for lung cancer with LDCT is of moderate net benefit in asymptomatic persons who are at high risk for lung cancer based on age, total cumulative exposure to tobacco smoke, and years since quitting smoking. The moderate net benefit of screening depends on limiting screening to persons who are at high risk, the accuracy of image interpretation being similar to that found in the NLST (National Lung Screening Trial), and the resolution of most false-positive results without invasive procedures.”
|ICSI Preventive Service Work Group Qualifications:|
The ICSI work group agrees with the evidence review and recommendations of the USPSTF as regards Lung Cancer Screening but would emphasis that the results of the National Lung Screening Trial (NLST) occurred within the context of a coordinated screening, and evaluation and treatment programs. Providing LDCT screening outside the confines of such a program is not evaluated. Only within a coordinated program will organizations be able to assure adequate shared decision-making, assess more fully the costs and benefits, the screening and treatment protocols, and the effects of the program over time. The most effective duration or frequency of screening is not known.
Overall, LDCT screening did not seem to result in significant long-term psychological distress, though assessment is limited. There are no RCTs of LDCT screening that evaluates associated benefits and harms related to incidental findings.
Shared decision-making is important for persons recommended for screening. The benefit varies with the risk, most net benefit for those at higher risk. Screening cannot prevent most lung cancers deaths, and smoking cessation remains essential. Lung cancer screening has substantial harms, most notably false-positives, incidental findings and over-diagnosis and their associated evaluation and treatment. Risks from radiation exposure and of anxiety are real, but their magnitude is uncertain. The decision to begin LDCT lung cancer screening should be the result of a thorough discussion of the benefits, limitations, and known and uncertain harms.
LDCT screening for lung cancer is a complicated process in which full discussion of the harms and benefits is essential at the outset. Screening should be conducted within a multidisciplinary coordinated care system with a comprehensive process for screening, image interpretation, management of findings, and evaluation and treatment of potential cancers. Overall, LDCT screening did not seem to result in substantial long-term psychological distress, although assessment has been limited. No studies reported long-term differences in anxiety or distress levels associated with LDCT in participants. No RCTs of LDCT screening evaluated the harms associated with screen-detected cancer, although overtreatment may be possible and could result in additional harms.
Shared decision-making is important for persons within the population for whom screening is recommended. The benefit of screening varies with risk because persons who are at higher risk because of smoking history or other risk factors are more likely to benefit. Screening cannot prevent most lung cancer deaths, and smoking cessation remains essential. Lung cancer screening has substantial harms, most notably the risk for false-positive results and incidental findings that lead to a cascade of testing and treatment that may result in more harms, including the anxiety of living with a lesion that may be cancer. Over-diagnosis of lung cancer and the risks of radiation are real harms, although their magnitude is uncertain. The decision to begin screening should be the result of a thorough discussion of the possible benefits, limitations, and known and uncertain harms.