Spatial correlation between in vivo imaging and immunohistochemical biomarkers: A methodological study.

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Accurate correlation between in vivo imaging and histopathology is crucial for cancer research.
• Dynamic contrast-enhanced computed tomography (DCE-CT) offers quantitative imaging parameters.
• Immunohistochemistry (IHC) provides detailed biomarker information at the cellular level.

Purpose of the Study:

• To develop and validate a method for voxel-by-voxel spatial correlation between DCE-CT parameters and IHC biomarkers.
• To investigate the relationship between DCE-CT parameters (Ktrans, Ve, Vi) and IHC biomarkers (Ki-67, HIF-1α, CD45) in laryngeal and hypopharyngeal carcinomas.

Main Methods:

• Digitization and registration of IHC-stained tumor slices with DCE-CT parameter maps.
• Application of the adiabatic approximation to the tissue homogeneity model for DCE parameter fitting.
• Calculation of both between-subject and within-subject (spatial) correlations using repeated measures correlation (rrm).

Main Results:

• No significant between-subject correlations were observed between IHC biomarkers and DCE-CT parameters.
• Significant within-subject correlations were found: Ve with Ki-67 and HIF-1α; Ktrans and Vi with CD45; Vi with Ki-67.
• The strongest within-subject correlation was between Ki-67 and HIF-1α (rrm = 0.35, P < .001).

Conclusions:

• The study demonstrates the technical feasibility of 3D spatial correlation analysis between in vivo imaging and histopathology.
• Within-subject correlations provide insights not captured by between-subject analyses.
• This method facilitates a deeper understanding of tumor biology through integrated imaging and biomarker analysis.