Underestimation of cancer incidence in Iran and necessity for establishing population-based cancer registries

Cancer in Iran 2008 to 2025: Recent incidence trends and short-term predictions of the future burden

Policymakers require estimates of the future number of cancer patients in order to allocate finite resources to cancer prevention, treatment and palliative care. We examine recent cancer incidence trends in Iran and present predicted incidence rates and new cases for the entire country for the year 2025. We developed a method for approximating population-based incidence from the pathology-based data series available nationally for the years 2008 to 2013, and augmented this with data from the Iranian National Population-based Cancer Registry (INPCR) for the years 2014 to 2016. We fitted time-linear age-period models to the recent incidence trends to quantify the future cancer incidence burden to the year 2025, delineating the contribution of changes due to risk and those due to demographic change. The number of new cancer cases is predicted to increase in Iran from 112 000 recorded cases in 2016 to an estimated 160 000 in 2025, a 42.6% increase, of which 13.9% and 28.7% were attributed to changes in risk and population structure, respectively. In terms of specific cancers, the greatest increases in cases are predicted for thyroid (113.8%), prostate (66.7%), female breast (63.0%) and colorectal cancer (54.1%). Breast, colorectal and stomach cancers were the most common cancers in Iran in 2016 and are predicted to remain the leading cancers nationally in 2025. The increasing trends in incidence of most common cancers in Iran reinforce the need for the tailored design and implementation of effective national cancer control programs across the country.

Cancer incidence in Iran in 2014: Results of the Iranian National Population-based Cancer Registry

BACKGROUND

We aimed to report, for the first time, the results of the Iranian National Population-based Cancer Registry (INPCR) for the year 2014.

METHODS

Total population of Iran in 2014 was 76,639,000. The INPCR covered 30 out of 31 provinces (98% of total population). It registered only cases diagnosed with malignant new primary tumors. The main sources for data collection included pathology center, hospitals as well as death registries. Quality assessment and analysis of data were performed by CanReg-5 software. Age standardized incidence rates (ASR) (per 100,000) were reported at national and subnational levels.

RESULTS

Overall, 112,131 new cancer cases were registered in INPCR in 2014, of which 60,469 (53.9%) were male. The diagnosis of cancer was made by microscopic confirmation in 76,568 cases (68.28%). The ASRs of all cancers were 177.44 and 141.18 in male and female, respectively. Cancers of the stomach (ASR = 21.24), prostate (18.41) and colorectum (16.57) were the most common cancers in men and the top three cancers in women were malignancies of breast (34.53), colorectum (11.86) and stomach (9.44). The ASR of cervix uteri cancer in women was 1.78. Our findings suggested high incidence of cancers of the esophagus, stomach and lung in North/ North West of Iran.

CONCLUSION

Our results showed that Iran is a medium-risk area for incidence of cancers. We found differences in the most common cancers in Iran comparing to those reported for the World. Our results also suggested geographical diversities in incidence rates of cancers in different subdivisions of Iran.