Low p27 kip1 expression in head and neck squamous cell carcinoma: association with risk factors and adverse outcomes

Background Squamous cell carcinoma (SCC) of head and neck is highly prevalent in South-asian countries, owing to high consumption of areca nut/gutka and chewing tobacco. p27 kip1 is a tumor suppressor gene, thought to be downregulated in oral squamous cell carcinoma. Therefore, in the present study we used immunohistochemical analysis to investigate an association between low p27 kip1 expression in SCC of the head and neck and adverse outcomes/risk factors. Methods Total 105 cases of SCC of head and neck excision specimens were selected from records of pathology department archives that underwent surgeries at Liaquat National hospital, Karachi from January 2008 till December 2013. Clinical and pathologic characteristics of patients were evaluated and p27 kip1 immunohistochemistry was applied on tumor blocks. Results In our study, low expression of p27 kip1 in SCC of head and neck was seen in 39(37.1%) cases while 66(62.9%) of the cases showed high expression for p27 kip1 . Significant association of p27 kip1 expression with pan/gutka usage ( p = 0.004), and recurrence ( p = 0.001) was noted; however, no significant association of p27 kip1 expression with other clinicopathologic features was seen. Multivariate binary logistic regression showed cases with history of pan/gutka usage were more likely to show low p27 kip1 expression. Similarly, we also found that recurrence was more likely to develop in patients with low expression of p27 kip1 in comparison to cases showing high p27 kip1 expression. Conclusion Loss of p27 kip1 expression is a significant event involved in the pathogenesis of SCC head and neck especially that of oral cavity. Significant association of gutka/areca nut with low p27 kip1 expression in our study suggests that loss p27 kip1 expression is a major event involved in areca nut induced SCC of head and neck in this part of the world; however, more large scale molecular based studies are required to validate this observation. Moreover, significant association of low p27 kip1 expression with tumor recurrence suggests its importance as a prognostic biomarker in SCC of head and neck.