Expresion of Ki67antigen in Oral and esophagus squamous cell carcinoma

Squamous cell carcinoma (SCC) is the most frequent malignant tumor of oral cavity and esophagus. Ki67 antigen, a proliferative cell marker, has a significant role in determining biological behavior of the tumors. The purpose of this study was to determine the frequency of Ki67 expression in squamous cell carcinoma of oral cavity and esophagus and their correlated factors. In this descriptive study 40 paraffin embeded blocks of patients with oral and esophagus S.C.C (20 of each) were selected,clinicopathological data were recorded and Immunohistochemical staining(1HC) was done on the newly cut sections for Ki67 antigen. The immunostained cells were counted on 10 HPF(high power fields) percent of positive cells(Labeling Index)was calculated and then cases classified in to low (LI≤48%) and high (LI>48%)levels. Statistical analysis was performed in SPSS,version 13 and Chi-square test. The results showed that 24 cases (60%) were male and 16 cases (40%) were female. The mean age of the patients was 65.3 ± 14.3. 45% of esophageal SCC specimens and 10% of oral SCC specimens were in high expression group. 55% of esophageal SCC and 90% of oral SCC were in low expression group and there was significant differences among oral and esophagus SCC (P<0.05). Age and sex were not correlated with Ki67 expression but the grade and size of the tumors were significantly correlated with the expression of Ki67. (Oral: P=0.01, P=0.03 respectively), (Esophageal: P=0.02, P=0.03 respectively). Ki67 expression in esophageal SCC was significantly higher than oral SCC which may define its more aggressive behavior. Age and sex were not correlated with Ki67 expression, but the grade and size of the tumors were significantly correlated with Ki67 expression.