Diffusion-weighted MRI in solitary pulmonary lesions: associations between apparent diffusion coefficient and...

Area of Science:

• Radiology
• Oncology
• Pathology

Background:

• Apparent diffusion coefficient (ADC) from diffusion-weighted imaging (DWI) is a potential tool for differentiating solitary pulmonary lesions (SPLs).
• The influence of histopathological parameters on ADC requires further elucidation to explain overlapping ADC values between malignant and benign SPLs.

Purpose of the Study:

• To investigate the associations between ADC and histopathological parameters in SPLs.
• To compare the diagnostic capability of ADC across different types of SPLs.

Main Methods:

• Quantification of histopathological parameters (cell density, nuclear-to-cytoplasm ratio, necrotic fraction, mucus presence, differentiation grade) in 52 malignant and 13 benign SPLs with available surgical pathology.
• Correlation analysis between ADC and histopathological parameters.

Main Results:

• Cell density (β = -0.40) and mucus presence (β = 0.77) were independently correlated with ADC in malignant SPLs.
• Accurate diagnosis rates for squamous carcinomas, adenocarcinomas without mucus, and malignant tumors with mucus were 100%, 82%, and 0%, respectively.
• ADC showed insufficient diagnostic capability for malignant SPLs with mucus and adenocarcinomas with low cell density.

Conclusions:

• Cell density and mucus presence are independently associated with ADC in malignant SPLs.
• ADC may more accurately diagnose squamous cell carcinoma as malignant.
• Malignant SPLs with mucus and low-density adenocarcinomas present diagnostic challenges when using ADC.