Social Disparity in Breast and Ovarian Cancer Incidence in Iran, 2003-2009: A Time Trend Province-Level Study

Purpose: This pioneering study aimed to investigate social disparities in breast cancer (BC) and ovarian cancer (OC) incidence rates among women across Iran's provinces from 2003 to 2009. Methods: Provincial level population distribution data pertaining to women were obtained from the Statistical Centre of Iran. Age-standardized incidence rates of BC and OC were gathered from the National Cancer Registry. Human Development Index was used as the provinces' social rank (SR), and rate ratio and Kunst and Mackenbach relative index of inequality were used to assess social disparities. Annual percentage change (APC) was calculated using joinpoint regression, and Spearman rank correlation was used to examine the association between APC and SR. Results: It was found that over the study period, annual incidence rates rose by 11.6% and 9.7% for BC and OC, respectively. Social disparities were substantial and stable in favor of provinces with lower SR in Iran, and were more profound for BC than OC. Correlations between APC and SR were small and nonsignificant for both BC and OC. Conclusion: The results showed that both BC and OC incidence increased in Iran during 2003 to 2009. There were positive associations between BC and OC incidence rates and the provinces' SR. This study's recommendations provide valuable information for health resource allocation pertaining to BC and OC control programs across provinces in Iran.