Lumpectomy and Radiation Therapy
Updated on July 3, 2025
Your doctors may recommend that you get radiation therapy after a lumpectomy. Radiation therapy uses high-energy X-rays or particles called protons to destroy cancer cells that might remain in the breast after the surgeon removes the tumor. This helps reduce the risk of the cancer coming back (recurrence).
Radiation therapy is recommended for most — but not all — people who get a lumpectomy.
Benefits of lumpectomy plus radiation
For most people with early-stage breast cancer, research shows lumpectomy plus radiation may be as effective as mastectomy. Early-stage breast cancer is cancer that hasn’t spread beyond the breast or underarm lymph nodes.
Some studies have found that people with early-stage breast cancer who received lumpectomy plus radiation lived longer than those who got a mastectomy. For example, a 2021 study of nearly 49,000 women diagnosed with early-stage breast cancer in Sweden found that overall survival and breast cancer-specific survival rates were higher for those who had lumpectomy and radiation than for those who had mastectomy with or without radiation.
Learn more about choosing between a lumpectomy and a mastectomy and making informed decisions about breast cancer surgery.
When does radiation therapy begin after a lumpectomy?
Radiation therapy after a lumpectomy can begin as early as one month after surgery. But most people begin radiation about two to three months after having a lumpectomy. This allows extra time for healing of the surgical site. If you’re receiving chemotherapy, radiation may begin afterward.
The schedule for the radiation therapy treatments can vary depending on whether you’re getting whole-breast or partial-breast radiation, whether the lymph nodes are also being treated with radiation therapy, and other factors.
If you’re getting whole-breast radiation, you’ll typically have one treatment a day, five days a week, for one to four weeks.
If you’re getting partial-breast radiation, you’ll typically have one treatment a day, five days a week, for one to two weeks. You might have the option of getting treatments every other day instead of on consecutive days.
If you want to get breast reconstruction surgery after a lumpectomy, your doctors may recommend that you schedule the reconstruction after you finish radiation therapy. This is because there is a risk that radiation therapy could cause wound-healing problems or infections in a reconstructed breast. It’s also because radiation therapy can cause changes to the appearance of the affected breast (for example, it can cause the breast to become smaller and can change the texture of the skin).
Is lumpectomy plus radiation therapy right for you?
You and your doctor will work together to decide whether lumpectomy plus radiation therapy is best for you.
Lumpectomy plus radiation therapy may be right for you if:
you have one tumor that is relatively small compared with the size of your breast
it’s important to you to keep as much of your natural breast tissue as possible
you want to avoid mastectomy and reconstruction, which is a longer surgery (or series of surgeries)
you’re able to commit to the schedule of radiation treatments your doctors are recommending
With some exceptions, lumpectomy plus radiation therapy may not be right for you if:
you’ve already had radiation to the same breast for an earlier breast cancer
you have a large amount of cancer in the breast or multiple areas of cancer in the same breast
you have a small breast and a large tumor and removing the tumor would lead to major changes in the appearance of your breast (and oncoplastic lumpectomy isn’t an option for you)
you have inflammatory breast cancer, which requires mastectomy
you have scleroderma
you’re pregnant, which makes radiation therapy unsafe
you can’t commit to a daily radiation therapy schedule
you have a high risk of developing a recurrence of breast cancer or a second breast cancer (due to family history of the disease, a genetic mutation, or other risk factors)
your surgeon has made several unsuccessful attempts to remove the breast cancer with lumpectomy
Your doctor might recommend a lumpectomy without radiation if:
you’ve been diagnosed with DCIS (ductal carcinoma in situ) that has a low risk of recurrence
you are over the age of 65 and have been diagnosed with early-stage, estrogen receptor-positive breast cancer
If you’ve been diagnosed with DCIS, your doctor might suggest using certain genomic tests to help decide whether radiation therapy after lumpectomy would offer more benefits than risks.
Researchers are continuing to study which people can safely skip getting radiation therapy after a lumpectomy. Some studies suggest, for example, that certain younger post-menopausal women with low-risk breast cancer and certain older women diagnosed with early-stage luminal A ductal breast cancer can take hormonal therapy alone after lumpectomy and skip radiation therapy.
Genomic Test Helps Decide Which DCIS Needs Radiation
Dec 8, 2023Hormonal therapy after lumpectomy
If you were diagnosed with hormone receptor-positive breast cancer and are having a lumpectomy, your doctors are likely to recommend that you take hormonal therapy medication for 5 to 10 years to reduce your risk of recurrence. Hormonal therapy is often prescribed for hormone receptor-positive breast cancer whether or not you’re getting radiation therapy.
Learn more about radiation therapy, including how it works, side effects, and more.
This information made possible in part through the generous support of www.BreastCenter.com.