Hyperspectral Imaging of Whole-Cell Region for Differentiating Cervical Squamous Intraepithelial Lesion Cytology

Cervical cytology offers a relatively safe and reliable method for cancer screening, but the tests contain vague grading criteria, such as atypical squamous cells, and cannot exclude high-grade squamous intraepithelial lesions (ASC-H) and atypical squamous cells of undetermined significance (ASC-US).

To explore distinct differentiation points among ASC-H, high-grade squamous intraepithelial lesions (HSIL), and non-keratinizing squamous cell carcinoma (SCC), and among ASC-US, low-grade squamous intraepithelial lesions (LSIL), and negative for intraepithelial lesion or malignancy, hyperspectral imaging analyses were performed in cells mounted on 150 Papanicolaou-stained specimens containing nine cervical cell types. Hyperspectral data were obtained from nuclei, cytoplasm, and whole-cell regions in 4841 cells without overlap at 15-nm increments in wavelength within the visible light spectrum (450-750 nm).

Significant differences in hyperspectral intensity were observed between ASC-H and HSIL at 487 nm to 517 nm (p < 0.05), as well as among SCC at 457 nm (p < 0.01). Further, hyperspectral intensity differences between ASC-US and LSIL were notable at multiple wavelengths with the lowest p-value (p = 0.006) at 532 nm. Interestingly, quantification of hyperspectral values revealed strong correlations between nucleus-to-cytoplasm ratio and hyperspectral intensity value of whole cell (R² = 0.8339, p < 0.001), indicating that intensity from the whole cell provided the most informative indicator of cervical cells.

These results suggest that hyperspectral analysis of whole cells offers a valuable tool for differentiating atypical squamous cells from other cell types.