Regional disparities in cancer survival in Iran: Insight from a National Surveillance of Cancer Survival in Iran (IRANCANSURV).

BACKGROUND AND OBJECTIVES

We aimed to investigate geographical disparity in cancer survival in 9 provincial population-based cancer registries in Iran from 2015 to 2016.

MATERIAL AND METHOD

In the current study, data from 90,862 adult patients (aged >15 years) diagnosed with cancer were retrieved from 9 population-based cancer registries across Iran. Five-year survival rates were estimated by applying relative survival approaches. We also applied the international cancer survival standard weights for age standardization. Finally, we calculated the excess hazard ratio (EHR) for each province adjusted for age, sex, and cancer sites to estimate the excess hazard ratio of mortality compared to the capital province (Tehran).

RESULTS

The largest gap in survival was observed in more curable cancer types, including melanoma (41.4%), ovary (32.3%), cervix (35.0%), prostate (26.7%), and rectum (21.4%), while the observed geographical disparity in lethal cancers such as lung, brain, stomach, and pancreas was less than 15%. Compared to Tehran, we found the highest excess hazard of death in Western Azerbaijan (EHR=1.60, 95% CI 1.51, 1.65), Kermanshah (EHR=1.52, 95% CI=1.44, 1.61), and Kerman (EHR=1.46, 95% CI=1.38, 1.53). The hazard ratio of death was almost identical in Isfahan (EHR=1.04, 95% CI=1.03, 1.06) and Tehran provinces.

CONCLUSION

Provinces with higher HDI had better survival rates. IRANCANSURV study showed regional disparities in cancer survival in Iran. Cancer patients in provinces with a higher Human Development Index (HDI) had a higher survival rate and lived longer compared to the patients in provinces with medium and low HDI regions.