Ki67, CD105, and α-SMA Expressions Better Relate the Binary Oral Epithelial Dysplasia Grading System of World Health Organization

Background: The binary system of oral epithelial dysplasia (OED) has never been investigated with reference to the carcinogenesis-related biomarkers. Hence, Ki67, CD105, and α-SMA immune-expressions were studied in oral potentially malignant disorders (OPMDs) to assess their relationship with the binary OED grading system of World Health Organization.

Methods: The study was carried out on paraffin-embedded tissues of 30 normal oral mucosa (NOM) and 140 OPMD cases. OPMD cases were classified into two groups "no/questionable/hyperkeratosis/mild"=low-risk epithelial dysplasia (LRED) and "moderate or severe"=high-risk epithelial dysplasia (HRED). The immunohistochemistry was carried out to evaluate the expression of Ki67, CD 105, and α-SMA antigen.

Results: According to the binary grading system of WHO, 69 (49.28%) cases were LRED, while 71 (50.71%) case showed HRED. There was significant increase in Ki67 labeling index (LI) from NOM to LRED to HRED (P=.000). Similarly, mean vascular density (MVD) also increased significantly from NOM to LRED to HRED (P=.000). The α-SMA expression was significantly higher in HERD compared to LRED and NOM (P=.000). A positive correlation was noted among Ki67 LI, MVD, and α-SMA expressions in NOM, LRED, and HRED (P=.000).

Conclusion: The expressions of ki67, CD105, and α-SMA markers compliment binary grading system of OED in OPMDS, thus justifying its use in clinical practice.