NCA - Screening for Lung Cancer with Low Dose Computed Tomography (LDCT) (CAG-00439R) - Decision Memo

Radiation DoseThe guidelines report that all screening and follow-up chest CT scans should be performed at low-dose (100-120 kVp [kilovoltage peak] and 40-60 mAs [milliampere-seconds] or less), unless evaluating mediastinal abnormalities or lymph nodes, where standard-dose CT with IV [intravenous] contrast might be appropriate (NCCN, 2020).There is a section in the NCCN guidelines on low-dose computed tomography (LDCT) acquisition, storage, interpretation, and nodule reporting (Lung-RADS) which describes radiation exposure based on the patients body mass index or BMI (NCCN, 2020). This section further describes the acquisition parameters for LDCT, such as slice width and slice interval, and how to report nodule parameters, such as size and density of the nodule found on LDCT (NCCN, 2020). Additionally, the NCCN guidelines make clear that for lung cancer screening, LDCT without intravenous contrast is currently recommended (instead of standard-dose CT) to decrease the dose of radiation. Although there is no strict definition of LDCT of the chest, it is usually approximately 10% to 30% of standard-dose CT. In most cases, LDCT has been shown to be as accurate as standard-dose CT for detecting solid pulmonary nodules, although nodule detection with LDCT may be limited in larger patients (NCCN, 2020). Further, to help ensure good image quality, all LDCT screening programs should use CT scanners that meet quality standards equivalent to or exceeding the accreditation standards of the ACR (NCCN, 2020). In the current NCCN guidelines, using low-dose techniques, the mean effective radiation dose is 1.5 millisievert (mSv) (standard deviation [SD], 0.5 mSv) compared with an average of 7 mSv for conventional CT. . . . Lower doses of radiation are now used for LDCT scans and these lower doses may be less dangerous (NCCN, 2020).Low Dose CT Reporting and Management SystemThe current NCCN guidelines state that to help ensure good image quality, all chest LDCT screening program should use CT scanners that meet the standards of the American College of Radiology (ACR). The ACR has developed Lung Imaging Reporting and Data System (Lung-RADS) to standardize the reporting and management of LDCT lung examinations (NCCN, 2020). The NCCN guidelines go on to state that the ACR developed Lung-RADS specifically for the lung cancer screening population in order to provide a standardized reporting and management tool for clinicians. Lung-RADS should be used, and not Fleischner Society Guidelines, when interpreting CT findings in an individual who has undergone lung cancer screening. . . . The NCCN Lung Cancer Screening Panel has harmonized Lung-RADS with the NCCN Guidelines for Lung Cancer Screening by revising the nodule management algorithm for screen-detected lung nodules (NCCN, 2020).Wood DE et al. National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology: Lung Cancer Screening. Version 1.2022  October 26, 2021. Available at https://www.nccn.org/professionals/physician_gls/pdf/lung_screening.pdf. Accessed December 21, 2021.In the newly updated National Comprehensive Cancer Network (NCCN), Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Lung Cancer Screening Version 1.2022, the NCCN Lung Cancer Screening Panel defined the risk status of high risk as age  50 years and  20 pack-year history of smoking with these high risk persons candidates for low dose CT (LDCT) screening (category 1) where shared patient/provider decision-making is recommended, including a discussion of benefits/risks (NCCN, 2020). For NCCN categories of evidence and consensus, Category 1 is defined as based upon high-level evidence, there is uniform NCCN consensus that the intervention is appropriate (Wood, NCCN; 2021).This section summarizes notable changes to the NCCN guidelines from 2020 to 2021.Evidence-based Guidelines Section: Within the algorithm image please note the most recent Guideline version has changed shared decision-making recommendation terminology from patient/physician to patient/provider.Changing Stopping Age From 77 years to 80 years Section: Removal of language stating that NCCN discusses uncertainty around Low Dose CT after 77 years.Smoking cessation section: Changing smoking cessation counseling is recommended to current smokers should be advised to quit smoking, and former smokers should be advised to remain abstinent from smoking.Please note that the NCCN Guidelines for Lung Cancer Screening contain detailed recommendations for evaluating and follow up on lung screening findings including immediate assessment of nodules that are highly suspicious for lung cancer. The NCCN Guidelines and the Lung-RADS recommendations have beenharmonized to provide consistent and clear recommendations to clinicians seeking to interpret LDCT scans.