en پژوهشي Research <div><strong>Introduction</strong>: Clinicopathologic characteristics of oral Squamous cell carcinoma (OSCC) affected by age, although it is controversial. In this study the differences in clinicopathological features of OSCC were compared between patients younger and older than 40 years&#39; old.<br> <strong>Materials and methods: </strong>In this retrospective study the histopathologic records of OSCC patients who underwent surgery in Cancer Institute of Iran during 2005-2015 were retrieved. The demographic and histopathologic features of patients in two groups of younger than 40 and older than 40 years old were recorded and descriptive analysis was used for statistical interpretation between groups.<br> <strong>Results: </strong>The most cases of OSCC in both groups was registered in males with 14.3% and 85.7% of cases in younger and older than 40, retrospectively. Tongue was the most prevalent anatomic location of OSCC in both groups (39%). Based on clinicopathologic features, most prevalent pathologic degree of OSCC in younger aged patients was moderately differentiated OSCC (14.5%). In patients older than 40, well differentiated OSCC (87.7%) was more prevalent.<br> <strong>Conclusion: </strong>Based on histopathologic features, the moderately differentiated and well differentiated OSCC were more in younger and older patients than 40, respectively. The finding suggests that OSCC has more malignant feature in young patients.</div> Squamous cell carcinoma, Oral cavity, Prognosis 49 51 http://jbrms.medilam.ac.ir/browse.php?a_code=A-10-359-1&slc_lang=en&sid=1 Ramin Ghafari ramin.ghaffari.s3@gmail.com 10031947532846002977 10031947532846002977 No Faculty of Dentistry, Shahed University, Tehran, Iran Noushin Jalayer Naderi jalayer@shahed.ac.ir 10031947532846002978 10031947532846002978 Yes Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Shahed University, Tehran, Iran Amirnader Emami Razavi razavinader@gmail.com 10031947532846002979 10031947532846002979 No 3. Iran National Tumor Bank, Cancer Biology Research Center, Cancer Institute of Iran, Tehran University of Medical Sciences, Tehran, Iran