Immunohistochemical expression of MIB-1 and PCNA in precancerous and cancerous lesions of uterine cervix.

ABSTRACT

BACKGROUND AND OBJECTIVE: The present study was done to analyze the immunoexpression of diagnostic markers (MIB-1 molecular immunology borstel and PCNA proliferating cell nuclear antigen) in grading cervical intraepithelial lesion (CIN) and squamous cell carcinoma (SCC) in cervix. SETTING AND DESIGN: Total 150 cervical biopsies were divided into four groups respectively; Group I-Normal (n = 32), Group II- CIN (n = 60), Group III- SCC (n = 44), Group IV- CA cervix (n = 14) respectively. MATERIALS AND METHODS: These biopsies were stained with monoclonal antibodies by streptavidin-- biotin method. Mean labeling index was calculated and grading was performed using the I--III scoring system. STATISTICAL ANALYSIS: Findings were correlated with age and menopausal status. Statistical analysis was done by using student sample‘t’ test and analysis of variance (ANOVA) by SPSS 10 package. RESULTS: MIB-1 immunostaining was positive in 112/150 (74.6%) cases and PCNA in 118 /150 (78.6%) cases. Labeling indices showed linear progression from normal to CIN to SCC to cancer lesion. Few cases of low-grade CIN lesion had high proliferative index. A significant positive correlation was found between age and PCNA and MIB-1 values (P < 0.05) when comparison was made for all the cases. CONCLUSION: These markers may be useful in identifying low-grade CIN lesion with high proliferative index. These cases should be kept for follow up studies so that proper intervention can be taken at an early stage. This method is simple and cost effective and can easily be done in formaline-fixed paraffin embedded tissues in a clinical laboratory for grading CIN and SCC lesions in cervix.