P53 & C-MYC ALTERATIONS IN CARCINOMA ORAL CAVITY & THEIR ROLE IN PREDICTING RESPONSE TO CHEMOTHERAPY

Aims: (1) To study p53 alterations & its role in predicting response to neo-adjuvant chemotherapy in patients of carcinoma oral cavity. (2) To study c-myc expression & its role in predicting response to neo-adjuvant chemotherapy in patients of carcinoma oral cavity. Methods and Material: Total of 30 patients with histologically proven squamous cell cancer of oral cavity having performance status of up to two according to the criteria proposed by eastern Co-operative Oncology Group were included in the study. After a detailed history and physical examination biopsy specimens were taken. All patients were given three cycles of neo-adjuvant chemotherapy consisting of cisplatin and 5-FU as continuous iv infusion at the intervals of 21 days. Patients then underwent surgery. All the samples including biopsy and surgery specimens were sent for immunohistochemistry. Research Methodology: The study was a prospective analysis. The Chi Square test (χ2) with Yates correction factor and Fischer exact test (P value) were used. Results: Of the total, 70% of cancer patients were positive for p53 and 60% were positive for c-myc mutations. The overall response rate was 36.6%. Statistically significant correlation was found between p53 & c-myc mutations, lymph node metastasis and response to chemotherapy. Significant correlation was also found between tumour grade and c-myc mutations. Conclusion: The presence of p53 and c-myc mutations effect the overall response to anti-cancer drugs and the analyses of these tumour markers from biopsy specimens, can help select those patients can be selected who are more likely to respond to chemotherapy. Analysis of oncogenes for responsiveness of oral cancer patients to chemotherapy is likely to improve overall cure rates and reduce morbidity due to anti-neoplastic agents.