Ten-Year Survival of Breast Cancer in Iran: A National Study (Retrospective Cohort Study).

Purpose: This study aimed to estimate the 5- and 10-year survival rates of breast cancer in Iran.

Methods: This retrospective cohort study was performed in 2019 on breast cancer patients registered in the national cancer registry system of Iran during 2007-2014. The patients were contacted to collect their information and status (alive or dead). Age and pathological type of tumor were categorized into five groups, and the place of residence was divided into 13 regions. The Kaplan-Meier method and the Cox proportional hazards model were used for data analysis.

Results: A total of 87,902 patients were diagnosed with breast cancer during the study, 22,307 of whom were followed-up. The 5- and 10-year survival rates of the patients were 80% and 69%, respectively. The mean age of the patients was 50.68 ± 12.76 years (median age, 49 years). About 2.3% of the patients were male. The 5- and 10-year survival rates were 69% and 50% in men, respectively. The highest survival rate was reported in the age group of 40-49 years, and the lowest rate was found in the age group of ≥70 years. Of all pathological types, 88% were found in the invasive ductal carcinoma group; the highest survival rate was reported in the noninvasive carcinoma group. The highest survival rate was reported in the Tehran region and the lowest in the Hamedan region. Based on the results, the Cox proportional hazards model, sex, age group, and pathological type were statistically significant differences.

Conclusion: This nationwide study performed on breast cancer patients indicated an improvement in the overall survival rate of these patients over the past years (the 5-year survival rate increased from 71% in 2011 to 80% in the present study), which might be attributed to advances in cancer management.