Breast Cancer Survival and Incidence: 10 Years Cancer Registry Data in the Northwest, Iran

Abstract

Methods: Data were obtained from East Azerbaijan cancer registry database for the 10-year period between 2007 and 2016. Survival analysis was performed to calculate the breast cancer-specific survival proportions and mortality rates. Joinpoint trend analysis was performed to estimate the incidence trend of the cancer.

Results: A total number of 4989 patients were recorded with primary diagnosis of breast cancer. Of them, we collected follow-up data for 1335 (1309 female and 26 male). The 10-year crude mortality rate was 3.34 (per 100,000). The one-, two-, three-, five-, and ten-year breast cancer-specific survival proportions were 0.92 (95% CI 0.91-0.93), 0.88 (95% CI 0.86-0.90), 0.84 (95% CI 0.83-0.86), 0.77 (95% CI 0.74-0.80), and 0.65 (95% CI 0.60-0.70), respectively. Over the study period, the age-standardized incidence rates increased from 21.68 to 36.99 (per 100,000) with an annual percentage change of 5.5 percent. Older individuals and males patients had significantly worse survival, and patients with high-grade tumors had significantly higher risk of mortality.

Conclusion: A relatively better survival for breast cancer in East Azerbaijan, Iran, was observed compared to the overall breast cancer-specific survival proportions and mortality rates in the country. However, it is still poor compared to the developed countries indicating that inappropriate treatment modalities might have played a role on this.

Figure 1

Kaplan-Meier survival curve, results for the test of equality of breast cancer-specific survival functions for the different variables in Northwest of Iran, between 2007 and 2016 in both sexes (a) age groups, (b) sex groups, (c) grades, and (d) morphologic types.