Cancer registration activity dates back to 1968 when the first cancer registration program was launched as a collaborativeresearch agreement between the International Agency for Research on Cancer (IARC) and the Institute for Health Studiesaffiliated to the Tehran University School of Public Health, in order to study the high incidence of esophageal cancer in theprovince of Mazandran (1,2,3). By 1971, this registry expanded its activity to cover whole area of Caspian littoral (fromNorth of Khorasan province to North of East-Azarbaijan province). This registry was able to generate population datafor ten years (1968 to 1979). Activity ceased in early 1980 and then in 1991, the registry started again to collect data oncancer cases referred to local cancer treatment facilities. Another population based cancer registry was established in Farsprovince in 1976, and expanded its activity to neighboring provinces (Bakhtaran and Khozestan provinces). The activitiesof this registry were limited to registration of histopathologically confirmed cases referred to the pathology departments,or cases referred for treatment to radiotherapy facilities in the Shiraz University Cancer Treatment Center. The Fars registryis still publishing cancer frequency data, without reference to a defined population (4,5).In 1984 a bill was passed from the National House of Representative requiring compulsory reporting of cancer cases tothe Ministry of Health and Medical Education; however, due to lacking of a functional system to manage this compulsoryreporting, no morbidity or mortality data were generated (6). In 1993, the Cancer Institute affiliated to Tehran Universityof Medical Sciences with a grant from Ministry of Health and Medical Education initiated a cancer registry program, toassist public health authorities in different regions of the country to establish regional population based cancer registries(7).This campaign resulted in series of activities in different regions including a collaborative research agreement with IARC(Dec. 1999) to establish a population based cancer registration in the Tehran metropolitan area.