Which Window Setting Is Best for Estimating Pathologic Invasive Size and Invasiveness?

Area of Science:

• Radiology
• Oncology
• Pathology

Background:

• The Eighth Edition of the Tumor Node Metastasis Classification System for Lung Cancer introduced changes to clinical and pathologic T descriptors.
• Limited data exist comparing lung and mediastinal window settings for estimating lung cancer invasive size (IS) and invasiveness.

Purpose of the Study:

• To determine the optimal computed tomography (CT) window setting for preoperative estimation of invasive size (IS) and invasiveness in lung adenocarcinomas.
• To compare the predictive accuracy of lung window consolidation diameter versus mediastinal window tumor diameter for IS and invasiveness.

Main Methods:

• Retrospective review of 1,167 patients with lung adenocarcinomas ≤3 cm.
• Measurement of three high-resolution CT variables.
• Correlation analysis of IS with CT variables, including factors predicting IS ≤5 mm and other invasiveness indicators.

Main Results:

• Mediastinal window tumor diameter showed stronger prediction of IS than lung window consolidation diameter (p < 0.001).
• Lung window consolidation diameter was a better predictor of IS than maximum tumor diameter in the lung window (p < 0.001).
• Mediastinal window tumor diameter demonstrated the highest accuracy in predicting lymphatic, vascular, and pleural invasion.

Conclusions:

• Measuring tumor diameter in the mediastinal window setting provides the most precise preoperative estimation of IS and invasiveness in lung adenocarcinomas.
• Mediastinal window tumor diameter is a critical preoperative measurement for lung cancer staging and treatment planning.