Metastatic breast cancer frequently spreads to the lungs, making the lungs one of its most common secondary sites.

Is it true that metastatic breast cancer frequently spreads to the lungs, making the lungs one of its most common secondary sites?

Unclear. Several peer-reviewed sources list the lungs among the most common metastatic sites of breast cancer, including a case report documenting pulmonary metastases and a study noting the lung as a preferred site. None of the retrieved items quantifies how frequently breast cancer spreads to the lungs, so the evidence supports the claim only in part.

Verdict: PARTIAL LEAN · 4 sources for, 0 against · Last checked 3 Oct 2026

The private library was unavailable for some searches in this check. Missing library results are not evidence against the claim.

Bilateral Choroidal Metastases Secondary to Metastatic Breast Cancer: A Case Report. (2026). hal.science. https://doi.org/10.59324/ejmhr.2026.4(5).09

Breast cancer lung metastasis: Molecular biology and therapeutic implications - PMC Lock. (n.d.). pmc.ncbi.nlm.nih.gov. https://doi.org/10.1080/15384047.2018.1456599

Isolated Uterine Metastasis of Invasive Ductal Carcinoma. (2013). doi.org. https://doi.org/10.1155/2013/793418

Sample Collection Study to Analyze Cerebral Spinal Fluid as a Biomarker for Brain Metastasis in Metastatic Breast Cancer. (2026). clinicaltrials.gov. https://clinicaltrials.gov/study/NCT07619534