An Epidemiologic study of Oral and Pharyngeal Nonsquamous Cell Malignant Tumors in Kerman province, Iran

Objective: The aim of the present study was to estimate crude and age-standardized incidence rates for oral and pharyngeal nonsquamous cell malignant tumors in Kerman province over a period of 11 years. Materials and Methods: The data used in this retrospective population-based study were extracted from the records registered in all pathology centers of Kerman province from 1991 to 2001. All confirmed cases of oral and pharyngeal nonsquamous cell malignant tumors were included in the study. The crude and age-standardized incidence rates per 1 million populations were calculated based on the 1996 census data and the population growth rate. Results: The total number of new nonsquamous cell cancers was 61, representing 18.2% of all oral and pharyngeal cancers in Kerman province. The average annual ageadjusted incidence rate per 1,000,000 population was 3.45 for both oral and pharyngeal tumors. The temporal variations in the annual incidence of oral and pharyngeal nonsquamous cell cancers was statistically significant (p=0.015). The most common types of nonsquamous cell malignant tumors in the oral cavity and pharynx were minor salivary tumors and lymphomas, respectively. The age-adjusted incidence was 0.74 for malignant salivary gland tumors, 0.66 for malignant melanomas, 0.4 for different types of sarcomas, and 1.65 for lymphomas. Conclusion: It can be concluded that the incidence rate and other features of nonsquamous cell malignant tumors of the oral cavity and pharynx in residents of Kerman province are similar to those reported by other investigators.