The Lung Reporting and Data System (LU-RADS): a proposal for computed tomography screening.
Despite the positive outcome of the recent randomized trial of computed tomography (CT) screening for lung cancer, substantial implementation challenges remain, including the clear reporting of relative risk and suggested workup of screen-detected nodules. Based on current literature, we propose a 6-level Lung-Reporting and Data System (LU-RADS) that classifies screening CTs by the nodule with the highest malignancy risk. As the LU-RADS level increases, the risk of malignancy increases. The LU-RADS level is linked directly to suggested follow-up pathways. Compared with current narrative reporting, this structure should improve communication with patients and clinicians, and provide a data collection framework to facilitate screening program evaluation and radiologist training. In overview, category 1 includes CTs with no nodules and returns the subject to routine screening. Category 2 scans harbor minimal risk, including <5 mm, perifissural, or long-term stable nodules that require no further workup before the next routine screening CT. Category 3 scans contain indeterminate nodules and require CT follow up with the interval dependent on nodule size (small [5-9 mm] or large [≥ 10 mm] and possibly transient). Category 4 scans are suspicious and are subdivided into 4A, low risk of malignancy; 4B, likely low-grade adenocarcinoma; and 4C, likely malignant. The 4B and 4C nodules have a high likelihood of neoplasm simply based on screening CT features, even if positron emission tomography, needle biopsy, and/or bronchoscopy are negative. Category 5 nodules demonstrate frankly malignant behavior on screening CT, and category 6 scans contain tissue-proven malignancies.
Department of Diagnostic Radiology, QE II Health Sciences Centre, Dalhousie University, Halifax, Nova Scotia, Canada. Electronic address: daria.manos@cdha.nshealth.ca.
Daria
D
Manos
Diagnostic Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Ontario, Canada.
Jean M
JM
Seely
McGill Health Center, Montreal General Site, McGill University, Montreal, Quebec, Canada.
Jana
J
Taylor
Department of Diagnostic Radiology, QE II Health Sciences Centre, Dalhousie University, Halifax, Nova Scotia, Canada.
Joy
J
Borgaonkar
Department of Medical Imaging, Women's College Hospital, University of Toronto, Toronto, Ontario, Canada.
Heidi C
HC
Roberts
Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
John R
JR
Mayo
D003937:Diagnosis, Differential; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D011829:Radiation Dosage; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed
LU-RADS; Low-dose computed tomography; Lung cancer screening; Lung nodules; National lung screening trial; Nodule risk