Prognostic Impact of Poor Differentiation of Squamous Cell Carcinoma in Treatment Naïve Node-Negative Early Oral Cancers.

We have conducted this study to understand the impact of poor differentiation (PD), as a sole poor prognostic factor, in early oral cancers. This was a retrospective analysis of a prospectively maintained database of clinically node-negative early T stage OSCC patients operated between 2012 and 2014. Impact of PD on the survival and role of adjuvant therapy in these patients was noted. Out of 1172 patients screened, 280 patients were found to be eligible for the study. 11.4% patients had PDSCC. It was found to be associated with tongue cancers and peri-neural invasion. It had a significant impact on OS and DFS (48.7 months vs 81.4 months, < 0.00 and 44.6 months vs 73.5 months, < 0.00 respectively. Hazard ratio for DFS: 4.08. Although patients with PDSCC had better survival with radiotherapy, but this was not statistically significant. Poor differentiation as a stand-alone factor impacts survival in patients with early oral cancer. It may be seen more often in patients with tongue cancer and may have associated PNI. The role of adjuvant therapy in such patients is not clear.