Oral Lymphoma Prevalence in Iranian Population: A Multicenter Retrospective Study

Background: Oral lymphoma is the second most common malignancy of the head and neck region after malignant epithelial tumors. Objectives: Considering the lack of a multicenter study on the frequency of oral lymphoma in Iran, this study aimed to assess the relative frequency of oral lymphomas in Iran during a 6-year period. Materials and Methods: This multicenter, retrospective, cross-sectional study was conducted in two phases. In the first phase, cases of oral lymphoma registered in the cancer research center (CRC) of Shahid Beheshti university of medical sciences were extracted. The patient records and pathology reports of these patients were retrieved from the archives and age, sex and microscopic type site of the lesions were evaluated. Results: Oral lymphoma accounts for 1% of head and neck malignancies and 8% of all lymphomas. From 2003 to 2008, a total of 437 new cases of oral lymphomas had been registered in the CRC. Diffuse large B-cell lymphoma was found to be the most common form of oral lymphoma in the 6-year period with 240 (54.9%) registered cases. The majority of detected cases were in the 6th and 7th decades of life with a male to female ratio of 1: 84. Tonsils were the most common site of occurrence of lymphoma in the oral cavity (77.8%). Conclusions: The age of onset, site of involvement, sex of patients, and histopathological subtype of oral lymphomas in the Iranian population were found to be similar to those of most other countries.