The following are treatment options for stage 0, or in situ, breast cancer. The types of treatments given are based on the unique needs of the woman with cancer and the type of in situ breast cancer.
There are 2 types of in situ breast cancer:
Ductal carcinoma in situ (DCIS) is the most common type of non-invasive breast cancer. Nearly all women diagnosed with this early stage breast cancer can be successfully treated.
The types of treatment for DCIS are:
Surgery is the primary treatment for DCIS. The types of surgery are:
Because cancer rarely spreads to the lymph nodes in DCIS, lymph nodes are not usually removed.
External beam radiation therapy is given after breast-conserving surgery, unless there is a medical condition that prevents a woman from receiving radiation.
Radiation therapy may also be done after a mastectomy if there is a high risk of the cancer recurring.
The type of hormonal therapy offered for DCIS is tamoxifen (Nolvadex, Tamofen). For more detailed information on specific drugs, go to sources of drug information.
Women with DCIS are not offered chemotherapy.
Lobular carcinoma in situ (LCIS), also called lobular neoplasia, is not really a precancerous condition or a true breast cancer. LCIS is a marker that a woman is at an increased risk of developing an invasive lobular or ductal breast cancer in the future.
The types of treatment for LCIS are:
After LCIS has been diagnosed, a woman may only need to be followed closely with regular mammography of both breasts to look for any changes early.
LCIS is almost always estrogen receptor positive. Hormonal therapy may be offered to a woman with LCIS to reduce the risk of breast cancer in the future.
The type of hormonal therapy offered is tamoxifen. For more detailed information on specific drugs, go to sources of drug information.
If LCIS is found on a breast biopsy, it is usually recommended that the area be removed to make sure that there are no other precancerous or malignant areas other than the LCIS.
Surgery may be offered to some women with LCIS who also have other factors that increase their risk of developing breast cancer. The type of surgery that may be offered is bilateral prophylactic mastectomy (removal of both breasts).
Women with LCIS are not offered chemotherapy.
Women with in situ breast cancer may be offered the opportunity to participate in clinical trials. For more information, go to clinical trials.
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