Trends in breast cancer incidence, age at diagnosis, and stage in Saudi Arabia, 2002-2022: a population-based study.

[BACKGROUND] Breast cancer is the leading cancer among women worldwide. Long-term national data from Saudi Arabia are limited; this study analyzed 21 years of registry data to describe incidence patterns and trends.

[METHODS] Data from the nationwide Saudi Cancer Registry (2002-2022), which ensures comprehensive coverage and high data quality, were analyzed. Age-standardized incidence rates (ASR), histology, and stage were extracted and summarized descriptively. Temporal trends were assessed using the Joinpoint Regression Program to estimate annual percent change (APC) and average annual percent change (AAPC) with 95 % confidence intervals.

[RESULTS] A total of 37,516 female and 639 male breast cancer cases were reported from 2002 to 2022. The ASR increased from 12.6 to 49.7 per 100,000 (AAPC 5.6 %, 95 % CI: 4.5-6.7, p < 0.0001). Incidence rose steadily with a sharp surge in 2020-2022, briefly interrupted by a COVID-19-related dip. Median age at diagnosis increased from 46 to 52 years (p = 0.003). The steepest increase occurred among women aged 70-74 (APC 8.3 %). Breast cancer increased from 21.1 % to >30 % of female cancers since 2015, while it remained rare in men (<1 %). Stage distribution shifted toward earlier detection, with localized disease rising from 26 % to 52 %.

[CONCLUSION] Breast cancer incidence in Saudi Arabia has increased at one of the fastest rates worldwide (AAPC 5.6 % vs. 0.5-1 % in high-income countries). The increase is accompanied by stage migration and an upward shift in median age at diagnosis. With the sharpest increases in older women and rising life expectancy, prioritizing expanded mammogram screening coverage and breast-care service capacity is essential for future planning.