Clinical and pathological correlation of P53 expression in oral cancers

In our study, we aimed to evaluate the overexpression of P53 in 155 oral squamous cell carcinomas and to correlate with various clinicopathological features like depth of invasion, lymph nodal involvement, and margin status, which affect the local recurrence and prognosis. This cross-sectional study included 155 oral squamous cell carcinoma patients who underwent surgical resection of primary and nodal disease. The histopathological and clinical features were noted. Immunohistochemical expression was reported, and other clinicopathological features were correlated. Statistical analysis was performed using SPSS software. In the present study, out of 155 patients, 127(81.9%) are males, and the majority are more than 50 years (55%). The most common site of oral carcinoma is the tongue, followed by buccal mucosa. An aberrant or mutational type of P53 was seen in 90 cases (58%), while the wild type was observed in 65 patients (42%). Expression of P53 is not similar in different sites of the oral cavity but is more frequently seen in the Gingiva, followed by retromolar trigone, lip, buccal mucosa, and tongue. There is a significant association between P53 expression and degree of tumor differentiation, T staging, and depth of invasion, involved margin, node positivity, and extranodal extension.

Correlation of p53 expression with Clinical Presentation and Prognosis of Oral Squamous Cell Carcinoma Patients: A Pilot Study

Mutations of p53 gene is one of the most common events in human cancers including oral squamous cell carcinoma (OSCC). However, its role in carcinogenesis and association with regard to prognosis is still under investigation and unclear. The aim was to study the expression of p53 in patients of OSCC and correlation with clinical presentation and prognosis. In this retrospective observational pilot study, we examined expression of p53 in 50 histologically diagnosed cases of OSCC and correlated it with initial clinical presentation and clinical events in follow up period. p53 expression was significantly negative (94%) in patients with history of only oral tobacco consumption while cases with additional history of smoking or alcohol were positive (p = 0.0001 and 0.011). On the other hand, aggressive course of the disease was found to be significant with p53 positivity in the form of lymph nodal extension (13 out of 17 cases) (p = 0.011) and recurrence (6 out of 10 cases) (p = 0.024). p53 was overexpressed (positive) in predisposing factors like smoking and alcohol but not in OSCC associated with chewing tobacco. p53 overexpression is also associated with advanced TNM stage. To the best of our knowledge, this is the first report where association of p53 overexpression and oral tobacco consumption associated OSCC was not observed and we recommend that carcinogenic events in chewing tobacco induced OSCC should be studied separately for its unique set of mutations.

Clinical and Histopathological Correlation of p16 and p53 Expression in Oral Cancer

p16 is overexpressed in oral squamous cell carcinoma patients who are positive for human papilloma virus. The p53 tumor suppressor gene is commonly mutated in human cancer. The aim is to correlate clinical and pathological features with p16 and p53 expression. This is a prospective, observational study of 50 consecutive cases (43 males and 7 females) who underwent surgery for oral cancer. p16 and p53 were determined by immunohistological staining. The results were obtained and analyzed using chi-square test (Statistical Software SPSS 21.0 version); p value ≤ 0.05 was considered significant. Of the 50 cases, p16 and p53 were overexpressed in 30% and 54% of patients, respectively. Overexpression of p16 was not significantly associated with age, subsites of oral cavity, or degree of differentiation. However, smokeless tobacco was significantly associated with p16 expression (p = 0.012). Similarly, overexpression of p53 was not correlated with age, subsites of oral cavity, or degree of differentiation. Seventy-five percent of poorly differentiated cancers had overexpression of p53 though this did not reach statistical significance (p = 0.279). p53 was overexpressed in smokers (80.95%) and those consuming alcohol (60%).