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Treatments for stage 0 breast cancer
The following are treatment options for stage 0 (non-invasive, or in situ) breast cancer. Your healthcare team will suggest treatments based on your needs and work with you to develop a treatment plan.
Ductal carcinoma in situ (DCIS) is the most common type of non-invasive breast cancer. Lobular carcinoma in situ (LCIS) increases a woman’s risk for developing breast cancer, but it is not considered a cancer.
Surgery is the main treatment for DCIS. Most women are offered breast-conserving surgery. If there are several areas of DCIS in the breast, doctors may do a mastectomy to make sure that all of the cancer is removed. Doctors do not remove lymph nodes under the arm (called axillary lymph node dissection) for DCIS because this cancer has not spread outside the duct in the breast.
To lower their risk of developing invasive breast cancer, some women with LCIS may choose to have their breasts removed (called a prophylactic mastectomy).
External beam radiation therapy is usually given after breast-conserving surgery for DCIS. It is used to lower the risk that cancer will come back (recur) in the breast, especially if there is high-grade DCIS. In rare cases, radiation therapy isn’t needed because the DCIS is low grade, it is only in one very small area of the breast and it is completely removed with surgery.
LCIS is not treated with radiation therapy.
Hormonal therapy may be offered after breast-conserving surgery for hormone receptor–positive DCIS. It can lower the risk of DCIS or invasive cancer in that breast and the other breast.
Hormonal therapy may be offered after a mastectomy to lower the risk of cancer in the other breast.
The most common type of hormonal therapy used is tamoxifen (Nolvadex, Tamofen). An aromatase inhibitor may be used for post-menopausal women.
Women with LCIS may be offered hormonal therapy to lower the risk that an invasive breast cancer will develop.
Find out more about hormonal therapy for breast cancer.
Many clinical trials in Canada are open to women with breast cancer. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.