Micro-Raman spectroscopic study of thyroid tissues

Area of Science:

• Biomedical Optics
• Molecular Spectroscopy
• Oncology

Background:

• Thyroid carcinomas represent the most common endocrine malignancy.
• Diagnostic challenges arise from inconclusive results in 20% of thyroid cancer diagnoses, leading to unnecessary surgeries.
• Raman spectroscopy shows potential for enhancing thyroid carcinoma diagnosis.

Purpose of the Study:

• To evaluate the efficacy of confocal Raman spectroscopy in discriminating between normal thyroid, goiter, and thyroid cancer tissues.
• To identify specific spectral regions and analytical methods for accurate tissue classification.

Main Methods:

• Confocal Raman spectroscopy was employed to analyze 30 thyroid tissue samples (normal, goiter, cancer).
• Statistical analyses including Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Binary Logistic Regression (BLR) were utilized for tissue discrimination.
• Analysis focused on specific spectral regions, notably the amide III band and the 1200-1400 cm⁻¹ range.

Main Results:

• Significant discrimination was achieved between tissue types.
• High concordance rates were observed: 89.2% for normal vs. cancer, 85.7% for goiter vs. cancer, and 80.6% for normal vs. goiter using the amide III region.
• The 1200-1400 cm⁻¹ spectral region effectively differentiated normal thyroid from goiter tissues, despite their similarities.

Conclusions:

• Raman spectroscopy is a valuable and rapid tool for the diagnosis of thyroid tissues.
• The technique demonstrates high accuracy in classifying normal thyroid, goiter, and thyroid cancer.
• Raman spectroscopy can aid in reducing indeterminate diagnoses and subsequent unnecessary surgical interventions.