Background: We have previously reported that macrophage migration-inhibitory factor (MIF) is associated with an unfavorable prognosis in hypopharyngeal carcinoma. Here, we quantified MIF expression in oral cavity carcinomas and looked for possible correlations with clinical outcome.
Materials and methods: MIF expression was assessed by immunohistochemistry in a cohort of 154 oral cavity carcinomas and was compared to eight specimens of tumor-free epithelia, 32 cases of low-grade dysplasia and 137 cases of high-grade dysplasia.
Results: Marked increases in MIF-immunostaining intensity and MIF-positive tissue areas were seen in carcinomas as compared to dysplasia (p<10(-6)). MIF expression showed no correlation with recurrence, but was significantly higher (p=0.01) when a second primary tumor occurred. In addition, HPV(+) malignancies exhibited lower MIF expression.
Conclusion: Our study revealed an association between tissue MIF levels and tumor progression in oral cavity carcinomas. Of note, high-level MIF expression was found in patients developing a second tumor during the follow-up period.