Oral cancer has been reported as the sixth most common malignancy in India. Survey conducted by National Institute of Public Health in 2011 has indicated 86 % of total oral cancers in world are contributed from India. Among many diagnostic methods of oral cancer detection, histological diagnosis acts as a powerful investigative tool providing important prognostic and predictive information relative to the disease status and biology. Malignant growth is acquired by the stepwise accumulation of defects in specific genes regulating cell growth. Two major pathways p53 and pRb deregulation is believed to result in tumor progression. Both pathways are mediated by p16INK4A .Owing to the higher predominance of cases observed at Basvatarakam Indo-American Cancer Hospital and Research Institute (BIACH & RI), Hyderabad present study focused on Immune histochemistry (IHC) method to identify importance and contribution of p16 as a molecular marker on clinical samples of Oral neoplasia. Grade of cancer can be useful for treatment plans and so the study was conducted to correlate levels of p16 expression in different grades of tumor. It can be inferred from our study that high p16 expression levels is associated with well differentiated OSCC (low grade), but however there existed no significant difference in the expression range for the different grades of tumors in regard to the percentage of expression with respect to the portions of tissue involved, hence suggesting that p16INK4A cannot be regarded as a significant prognostic tumor marker on the stand alone results of IHC.
