Evaluation of the Ki-67 and MCM3 Expression in Cytologic Smear of Oral Squamous Cell Carcinoma

Statement of the problem: squamous cell carcinoma (scc) is the most frequent oral cancer whose 5-year survival rate is 80% for early-detected lesions and nearly 30-50% for advanced lesions. early detection of oral cancers and precancerous lesions can improve the patient’s survival and decrease the morbidity. purpose: this study aimed to evaluate and compare the ki-67 and mcm3 expression in cytologic smear of oral scc (oscc). materials and method: we examined 48 oral brush biopsies including 28 oscc and 20 healthy non-smoking samples. immunocytochemistry staining was performed for ki-67 and mcm3 by using an envision-labeled peroxidase system, and labeling index (li) was calculated. results: out of 28 oscc cases, 27(96.4%) cases contained mcm3 positive cells and 22(78%) cases contained ki-67 positive cells. all normal mucosa were ki-67 and mcm3 negative. mcm3 and ki-67 li were significantly higher in oscc than normal mucosa (p< 0.001). mcm3 li was significantly higher than ki-67 li in oscc group (p< 0.001). conclusion: immunocytologic evaluation of ki-67 and mcm3 can be used for early detection of oscc. furthermore, mcm3 may be a more sensitive cytologic biomarker than ki-67 in scc patients.