What is the difference between Fleischner guidelines and Lung-RADS (Lung Computed Tomography Screening Reporting and Data System)?

From the Guidelines

The Fleischner Society guidelines and Lung-RADS (Lung Reporting and Data System) are both classification systems for managing pulmonary nodules, but they serve different purposes and have distinct applications, with Fleischner guidelines primarily used for incidental pulmonary nodules and Lung-RADS for structured reporting in screening programs. The key difference between the two guidelines is their intended use: Fleischner for incidental findings in the general population and Lung-RADS for formal lung cancer screening examinations. According to the most recent study 1, the guidelines provide recommendations based on nodule size, appearance, and patient risk factors, focusing on follow-up intervals for surveillance. Some key points to consider when using these guidelines include:

• Nodule size: smaller nodules (< 6 mm) may not require follow-up, while larger nodules (≥ 8 mm) may require more aggressive management
• Patient risk factors: high-risk patients may require more frequent follow-up and additional testing
• Follow-up intervals: the guidelines provide recommendations for follow-up intervals based on nodule size and patient risk factors
• The use of Lung-RADS is specifically designed for standardizing lung cancer screening CT interpretation and management in high-risk populations, as stated in the study 1 In contrast, the Fleischner guidelines are more general and can be applied to incidental pulmonary nodules found on CT scans performed for reasons other than lung cancer screening, as mentioned in the study 1. Clinicians should select the appropriate system based on the clinical context—Fleischner for incidental nodules and Lung-RADS for formal lung cancer screening examinations, as recommended by the study 1. Understanding both systems helps ensure appropriate management of pulmonary nodules and effective communication between radiologists and referring physicians. It is also important to consider the patient's individual risk factors and medical history when making management decisions, as noted in the study 1. By using the appropriate guideline and taking into account individual patient factors, clinicians can provide optimal care for patients with pulmonary nodules. The studies 1 provide a comprehensive overview of the guidelines and their applications, and can be used to inform clinical decision-making.

From the Research

Comparison of Fleischner Guidelines and LungRADS

• The Fleischner guidelines and LungRADS are two systems used for the management of lung nodules detected on computed tomography (CT) scans 2, 3.
• LungRADS is a system specifically designed for lung cancer screening, while the Fleischner guidelines are more general and apply to all types of lung nodules 4, 5.
• A study comparing the PanCan model and LungRADS found that they had similar accuracy in estimating the probability of cancer in screening-detected solid nodules, but there was discordance between the two models in certain subgroups 4.
• Another study found that LungRADS category 4 nodules had a high frequency of cancer, and that the cancer risk remained high even if positron emission tomography (PET) was negative 2.
• The use of PET-CT in the diagnostic work-up of screening-detected lung nodules has been evaluated, and it was found to have high sensitivity and specificity for differentially diagnosing malignant nodules, especially for nodules ≥15 mm and solid nodules 5.
• Recent technological developments in CT and magnetic resonance imaging (MRI) have improved pulmonary nodule detection and lung cancer staging, including dynamic imaging studies, dual energy CT, computer-aided detection and diagnosis, and imaging-assisted nodule biopsy approaches 6.

Key Differences

• The main difference between the Fleischner guidelines and LungRADS is that LungRADS is specifically designed for lung cancer screening, while the Fleischner guidelines are more general 3, 4.
• LungRADS has a more detailed categorization system, with six categories (0-5) compared to the three categories (benign, probably benign, and suspicious) in the Fleischner guidelines 2, 5.
• The management recommendations for lung nodules also differ between the two systems, with LungRADS providing more specific guidance on follow-up and biopsy for each category 4, 5.

Clinical Implications

• The choice of guidelines (Fleischner or LungRADS) may depend on the specific clinical context and the type of lung nodule detected 3, 4.
• Clinicians should be aware of the strengths and limitations of each system and use their clinical judgment when managing lung nodules 2, 5.
• Further research is needed to compare the performance of the Fleischner guidelines and LungRADS in different clinical settings and to develop more effective management strategies for lung nodules 4, 6.