P53 expression and polysomies of chromosome 9, 17 in head and neck cancer prognosis

Sixty-nine cases of head and neck squamous cell carcinoma were examined by immunohistochemistry for p53 and chromosome in situ hybridization for chromosome 9 and 17 to determine the relationship between p53 expression and polysomies of chromosome 9 and 17 with the development of a second primary tumor as well as recurrence of primary tumor of head and neck squamous cell carcinoma. We found early expression of p53 in the normal and premaligant lesions adjacent to tumor which was associated with a gradual increase in the fraction of positive nuclei as well as numbers of cancer. We also found statistically significant increments of polysomies of chromosome 9 and 17 in terms of the polysomy index seen through the histologic changes occuring during multistep tumorigenesis. Our results could not demonstrate statistically significant correlation between p53 expression and PI 9 and 17 in tumorigenesis. Interestingly, however, there was a strong correlation between p53 expression and second primary tumor as well as recurrence of primary tumor. The p53 expressed group had a seven fold increased incidence in developing second primary tumor and a two and a half times increased incidence for recurrence of primary tumor, compared to the non-expressed group. We conclude that p53 expression and polysomies of chromosome 9 and 17 have an important role in multistep tumorigenesis in HNSCC. There was no significant correlation between p53 expression and polysomies of chromosome 9 and 17. However, the expression of p53 was statistically significant for association with second primary tumor and recurrence of primary tumor of head and neck squamous cell carcinoma.