Secondary cancers
- Medical Review: Margret Rosenzweig, PhD, CRNP-C, AOCNP, FAAN
In very rare cases, some breast cancer treatments can cause a different cancer in a different part of the body, usually many years later. This is called a secondary cancer.
A secondary cancer is different from a spread of the original cancer. These cancers may be related to treatment-caused cellular changes.
Secondary cancers are very rare, and your doctors will help make sure the risk of a secondary cancer is much smaller than the benefit of your breast cancer treatment. Still, it’s understandable to have concerns about secondary cancers. Talk with your providers about any questions or concerns so they can help you understand the level of risk.
What causes secondary cancers?
Some breast cancer treatments can increase the risk of a secondary cancer:
- Chemotherapy. Some chemotherapy medicines can increase the risk of blood cancers such as leukemia. Chemotherapy medicines that may increase the risk of leukemia include, but are not limited to:
- Radiation therapy. Radiation can damage bone marrow, the fatty tissue inside your bones that makes blood cells. This can increase your risk for blood cancers such as myelodysplasia or leukemia. Radiation may also cause an increased risk of solid tumors, which usually develop in or near the radiated areas.
- Hormonal therapy. Tamoxifen slightly increases the risk of developing uterine cancer, mostly in women over age 50. If you are taking tamoxifen, your care team will recommend regular gynecologic exams to monitor your risk.
Breast reconstruction is surgery to rebuild the breast after mastectomy removes the cancer and all of the breast tissue. Certain types of textured breast implants used in some breast reconstructions can increase the risk of a secondary cancer.
Rarely, these implants have caused breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). In the U.S., fewer than 500 cases have been reported. If you had breast reconstruction with textured implants, talk with your plastic surgeon about whether they increase the risk of implant-associated anaplastic large cell lymphoma (BIA-ALCL).
Learn more on the implant reconstruction page.
Managing the risk of a secondary cancer
While secondary cancers are rare, it’s important to talk with your care team about certain risks or treatment side effects you may experience. This includes side effects that happen during or after treatment.
Here are some questions to ask your care team:
- Do any of my treatments increase the risk of a secondary cancer?
- If yes, what are the signs and symptoms?
- If I have a symptom, how soon should I let you know?
- Are there any exams or tests I will need to monitor this risk?
- How often should I schedule follow-up visits?
Knowing your individual risk for these rare cancers can help you take steps to manage it. You and your care team can work together on a follow-up plan that’s right for you.
Learn more about When to have follow-up visits.
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Reviewed and updated: December 18, 2025
Reviewed by: Margret Rosenzweig, PhD, CRNP-C, AOCNP, FAAN
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Living Beyond Breast Cancer is a national nonprofit organization that seeks to create a world that understands there is more than one way to have breast cancer. To fulfill its mission of providing trusted information and a community of support to those impacted by the disease, Living Beyond Breast Cancer offers on-demand emotional, practical, and evidence-based content. For over 30 years, the organization has remained committed to creating a culture of acceptance — where sharing the diversity of the lived experience of breast cancer fosters self-advocacy and hope. For more information, learn more about our programs and services.