Overview and strategic management of subsolid pulmonary nodules

Area of Science:

• Pulmonology
• Radiology
• Oncology

Background:

• Recent lung cancer screening programs provide data correlating histologic findings with subsolid pulmonary nodules on CT.
• Subsolid nodules include pure ground-glass nodules (GGNs) and part-solid GGNs.
• Serial CT imaging shows stepwise progression in some nodules, with increased size and density.

Purpose of the Study:

• To introduce the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification for lung adenocarcinoma.
• To highlight the correlation between histologic findings and subsolid pulmonary nodules on CT.
• To propose standardized management guidelines for subsolid pulmonary nodules.

Main Methods:

• Review of recent lung cancer computed tomography (CT) screening program data.
• Analysis of serial CT imaging to observe nodule progression.
• Application of the new lung adenocarcinoma classification system.

Main Results:

• Established a correlation between lung adenocarcinoma histology and subsolid pulmonary nodules (GGNs and part-solid GGNs).
• Observed stepwise progression in a subset of nodules, including size and density increases.
• Identified subsolid nodules as having a higher incidence of malignancy and slower growth rate.

Conclusions:

• A new lung adenocarcinoma classification system has been proposed.
• Subsolid pulmonary nodules require specific management strategies.
• Long-term, low-dose CT follow-up (≥3 years) is recommended for subsolid nodules.
• Radiologists must be familiar with new terminology and management strategies for subsolid pulmonary nodules.