CT Texture Analysis-Correlations With Histopathology Parameters in Head and Neck Squamous Cell Carcinomas

Abstract

Introduction: Texture analysis is an emergent imaging technique to quantify heterogeneity in radiological images. It is still unclear whether this technique is capable to reflect tumor microstructure. The present study sought to correlate histopathology parameters with texture features derived from contrast-enhanced CT images in head and neck squamous cell carcinomas (HNSCC). Materials and Methods: Twenty-eight patients with histopathological proven HNSCC were retrospectively analyzed. In every case EGFR, VEGF, Hif1-alpha, Ki67, p53 expression derived from immunhistochemical specimen were semiautomatically calculated. Furthermore, mean cell count was estimated. Texture analysis was performed on contrast-enhanced CT images as a whole lesion measurement. Spearman's correlation analysis was performed, adjusted with Benjamini-Hochberg correction for multiple tests. Results: Several texture features correlated with histopathological parameters. After correction only CT texture joint entropy and CT entropy correlation with Hif1-alpha expression remained statistically significant (ρ = -0.60 and ρ = -0.50, respectively). Conclusions: CT texture joint entropy and CT entropy were associated with Hif1-alpha expression in HNSCC and might be able to reflect hypoxic areas in this entity.

Keywords: CT; HNSCC; Hif1-alpha; Ki67; texture analysis.

Figure 1

One case with a histopathologically confirmed HNSCC: postcontrast CT (A) in axial slices with placed ROIs and the corresponding PET overlay (B). A cervical lymph node metastasis is also displayed. (C) EGFR-stained specimen. The stained area is 99,841 μm². (D) Her 2-stained specimen. The stained area is 79,667 μm². (E) Hif1-alpha stained specimen. The stained area is 14,896 μm². (F) VEGF stained specimen. The stained area is 373 μm². (G) P53 stained specimen. No immunreaction is seen.

Figure 2

Correlation heat map of the investigated CT texture features and histopathology parameters.

Figure 3

(A) Correlation graph showing the correlation between texture feature histogram entropy and Hif1-alpha expression. The correlation coefficient is ρ = −0.60. (B) Correlation graph showing the correlation between texture feature texture joint entropy and Hif1-alpha expression. The correlation coefficient is ρ = −0.50.