Expression of MUC1 mucin in potentially malignant disorders, oral squamous cell carcinoma and normal oral mucosa: An immunohistochemical study

Background: Mucins alteration in glycosylation is associated with the development and progression of malignant diseases. Therefore, mucins are used as valuable markers to distinguish normal and disease conditions. Many studies on MUC1 expression have been conducted on variety of neoplastic lesions other than head and neck region. None of the study has made an attempt to show its significance in potentially malignant disorders (PMDs) and oral squamous cell carcinoma (OSCC). Hence, ours is one of the pioneer studies done to assess and evaluate the same. Aims: This study aims to compare and correlate the expression of MUC1 mucin protein in normal oral mucosa (NOM), PMD's and OSCC by immunohistochemical method. Materials and Methods: Institutional study, archived tissue sections of OSCC (n = 20), PMD's (n = 20) and NOM (n = 20) were immunostained for MUC1 mucin and percentage of positive cells evaluated. Results obtained were statistically analyzed using Kruskal-Wallis test, Mann-Whitney test and Student's t-test. Results: The mean MUC1 mucin positive cells in the study groups were as follows, 40% in OSCC, 28% in PMD's and 0.75% in NOM. Higher mean immunohistochemical score was observed in OSCC group followed by PMD's group and NOM group. The difference in immunohistochemical score among the groups was found to be statistically significant (P < 0.001). Conclusion: The result of the current study suggests that determination of MUC1 mucin expression may be a parameter in the diagnosis of malignant behavior of PMD's to OSCC. MUC1 mucin expression may be a useful diagnostic marker for prediction of the invasive/metastatic potential of OSCC.