New Study Questions Effectiveness of Breast Cancer Screening Program in Austria

A recent study conducted in Salzburg has cast doubt on the effectiveness of Austria's breast cancer screening program, which was introduced in 2014 with the aim of detecting mammary carcinomas at earlier stages. The findings suggest that the program has not significantly improved outcomes compared to prior opportunistic screening methods.

Researchers from the University Hospital for Internal Medicine III in Salzburg evaluated the incidence of advanced breast cancer stages following the implementation of the national screening initiative. Their analysis revealed no statistically significant reduction in the diagnosis of advanced breast cancer cases since the program's inception.

Despite these findings, the researchers emphasized the importance of regular screenings for women aged 45 to 74, as individual risk factors still necessitate early detection to lower the likelihood of advanced disease.

The study highlights critical concerns, particularly as approximately 5,600 women in Austria are diagnosed with breast cancer annually, with around 1,600 succumbing to the disease each year despite advancements in treatment. Historically, mammography-based screening programs have been lauded for their role in reducing breast cancer mortality, with the prevailing belief that early detection leads to better treatment outcomes and higher survival rates.

To assess the impact of the screening program, researchers analyzed data from the Salzburg cancer registry, which tracks all diagnosed cancer cases in the region. They focused on women aged 45 to 69 diagnosed with breast cancer from 2010 to 2022, comparing data from two distinct periods: before the screening program (2010-2013) and after its implementation (2016-2019).

The analysis revealed that the distribution of cancer stages at diagnosis did not differ significantly between the two periods. Although there was a slight decrease in the proportion of stage IV diagnoses from 9.4% to 4.5%, this change was not statistically significant. The study found no meaningful differences in early-stage (0 to I) versus advanced-stage (II to IV) cases.

Before the program's launch, 12.2% of cases were identified as precursors to breast cancer, while this figure only marginally increased to 13.4% post-implementation. Similarly, the percentage of stage I diagnoses remained relatively stable, with 44.1% before the program and 46.2% afterward.

In terms of participation rates, the study indicated that the proportion of women participating in the screening program remained consistent at around 45% from 2014 to 2021. Overall mammography coverage for women aged 45 to 69 was estimated at 51%, which closely mirrored the pre-program opportunistic screening rate of approximately 55%.

Notably, the researchers could not determine whether the introduction of the screening program led to a decrease in breast cancer mortality rates. They focused primarily on the cancer stage at diagnosis, as this metric is less influenced by treatment outcomes and provides a clearer measure of screening effectiveness.

Advancements in breast cancer therapies over recent years have contributed to a disparity between the incidence of the disease and mortality rates. An American simulation study indicated that improvements in treatment for breast cancer stages I to III contributed significantly to the reduction in mortality rates, while screening played a comparatively smaller role.

As of early 2023, the age range for the Austrian screening program has been expanded to include women aged 45 to 74. Despite this, participation remains low, with only about 41% of women in this age group utilizing mammography for early detection. The health ministry's website notes that every woman in this demographic automatically qualifies for a mammogram, receiving invitations for screenings every two years. The authors of the study suggest that increasing participation rates among women could lead to more favorable outcomes in breast cancer management.