Immunological Microenvironment Diversity in Homogeneous and Non-Homogeneous Oral Leukoplakia

Area of Science:

• Oral pathology
• Immunohistochemistry
• Cancer research

Background:

• Oral leukoplakia (OL) is a potentially malignant disorder with variable malignant transformation rates (7.2–9.5%).
• Understanding immune cell roles in OL progression is crucial for risk stratification.

Purpose of the Study:

• To investigate immune cell differences in homogeneous versus non-homogeneous OL.
• To correlate immune cell infiltration with dysplasia grades and malignancy risk.

Main Methods:

• Semi-quantitative assessment of T lymphocytes (CD3+), B lymphocytes (CD20+), macrophages (CD68+), plasma cells (CD138+), and CD9+ cells in 50 OL cases.
• Manual counting by two morphologists using a 4-point scale.

Main Results:

• Dysplastic OL, both homogeneous and non-homogeneous, showed higher CD138+ and CD68+ cell proportions.
• Non-homogeneous OL with dysplasia exhibited increased CD3+ and CD20+ lymphocyte infiltration.
• A positive correlation was found between CD9+ cells and epithelial labeling in OL of varying thickness.
• CD138 and CD9 expression suggests epithelial-mesenchymal interactions, with opposing patterns in epithelial vs. immune cells.

Conclusions:

• Evaluating CD3, CD20, CD9, CD138, and CD68 expression enhances malignancy risk assessment in dysplastic OL.
• Non-homogeneous OL with dysplasia presents distinct immune cell profiles, particularly increased T and B lymphocytes.
• Immune cell profiling offers a valuable tool for predicting OL malignant potential.