A study of Ki-67 expression and its clinicopathological determinants in nondysplastic oral leukoplakia.

CONTEXT

Oral cancer is the third most prevalent malignancy in India. Leukoplakia is its most common precursor lesion.

AIMS

This study aimed at evaluation of the Ki-67 expression and thereby detection of the dysplastic potential in histopathologically nondysplastic oral leukoplakia (OL). Secondarily, another purpose was to correlate various clinicopathological factors with the labeling indices (LIs) of Ki-67 in those cases as well.

SETTINGS AND DESIGN

In total, 97 OL cases were examined. Relevant clinical and demographic information was retrieved from the pro forma, prefilled by the patients themselves during their first visit.

SUBJECTS AND METHODS

Ki-67 immunohistochemical staining was performed on paraffin-embedded tissue samples. Its LIs were calculated and correlated with different clinicopathological parameters using statistical software SPSS version 16.0.

RESULTS

58.8% (57 cases) lesions exhibited a Ki-67 positivity of ≤5%, and 25.8% (25 cases) lesions exhibited it in the range of 6%-25%. Only 15 (15.4%) patches were stained positively between 26% and 60%. Patients' age beyond 50 years, nonhomogeneous leukoplakia, and tobacco addiction were the significant risk factors for high Ki-67 scores ( < 0.05).

CONCLUSIONS

Ki-67 is an essential immunohistochemical marker for epithelial dysplasia in OL, especially when the conventional histopathology fails to appreciate the same. In this purpose, Ki-67 labeling on a routine basis delivers the most convenient results for patients aged above 50 years, and/or addicted to tobacco products, and/or suffering from nonhomogeneous patches.