> For the complete documentation index, see [llms.txt](https://docs.finngen.fi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.finngen.fi/finngen-data-specifics/red-library-data-individual-level-data/what-phenotype-files-are-available-in-sandbox-1/other-registers/finnish-cancer-registry-breast-cancer-screening.md).

# Finnish Cancer Registry: Breast cancer screening

### Sandbox directory

The data is available in the following Sandbox directory:

`/finngen/library-red/finngen_R[RELEASE]/cancer_screening_1.0`

Please refer to the readme file in the sandbox directory for full details of the available data.

### Description

Women 50-69 years of age are invited by personal letter to take part in breast cancer screening, or mammography, every two years.

More than 80% of the women invited to attend are screened. Fewer than 3% of participants are invited for further testing, i.e. ultrasound examination and biopsy, and of the individuals invited for further testing about 20% have breast cancer.

A total of about 5000 women in Finland each year are diagnosed with breast cancer. Of those, over half belong to the screening age group of 50-69. Some two-thirds of female breast cancers are detected by screening.

FinnGen breast cancer screening data consists of measurements of breast cancer screening (e.g. radiologists’ reports, biopsy, surgery), since 1992.

{% hint style="info" %}
More information about the data is available from the [Finnish Cancer Registry (Breast cancer screening)](https://cancerregistry.fi/screening/breast-cancer-screening/).
{% endhint %}