What is breast-conserving surgery?

Your surgeon may suggest having breast-conserving surgery (a wide local excision or WLE). You might also hear it called a lumpectomy. Breast-conserving surgery aims to keep as much of the breast tissue and the shape of the breast as possible. After breast-conserving surgery most women are pleased with the appearance of their breast.

During a wide local excision (WLE), the surgeon removes the DCIS and some of the normal looking tissue around it (the margin).

A doctor inserts a fine wire into the areas of DCIS before surgery. This is called wire localisation. It marks the area to be removed, and means the surgeon can find it more easily. The doctor uses an x-ray or ultrasound to help them find the right area. During the operation, the wire is then removed with the area of DCIS.

Some women have a radioactive liquid or radioactive seed injected into the DCIS instead of having wire localisation. The surgeon uses a handheld machine that can detect the radioactivity and the area of DCIS. This is called radio-guided occult lesion localisation (ROLL).

If a large area of DCIS is removed, the breast will be smaller than before. If this happens, the surgeon can also reduce the size of your other breast, to make your breasts look even. This is called a therapeutic mammoplasty.

Radiotherapy after breast-conserving surgery

After breast-conserving surgery, some women are advised to have radiotherapy. This is to reduce the risk of:

  • DCIS coming back
  • an invasive cancer developing.

Radiotherapy is usually offered if the DCIS is high grade. If the area of DCIS was very small and low or intermediate-grade, you may only need a WLE.

Having breast-conserving surgery followed by radiotherapy, is as effective at treating DCIS as having a mastectomy.

Clear margins

After breast-conserving surgery, a pathologist examines the tissue that has been removed under a microscope. A pathologist specialises in looking at tissue samples and cells under a microscope. They check the area (margin) around the cancer. If they find DCIS or cancer cells close to the edges, you will need another operation to remove more tissue. Having clear margins reduces the risk of DCIS or invasive cancer coming back.

Your surgeon will usually recommend a mastectomy if they do not think another breast-conserving operation is likely to be successful. If you have a mastectomy, you will also be offered breast reconstruction.

About our information

  • References

    Below is a sample of the sources used in our ductal carcinoma in situ (DCIS) information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    European Society for Medical Oncology. Primary breast cancer: ESMO clinical practice guidelines for diagnosis, treatment and follow-up. Annals of oncology 26 (supplement 5): v8–v30. 2015. 

    Morrow M, et al. Chapter 79: malignant tumors of the breast. DeVita, Hellman and Rosenberg’s cancer: principals and practice of oncology (10th edition). Lippincott Williams and Wilkins. 2014.

    National Institute for Health and Care Excellence (NICE). Early and locally advanced breast cancer: diagnosis and management. July 2018.

    Scottish Intercollegiate Guidelines Network. SIGN 134. Treatment of primary breast cancer: a national clinical guideline. September 2013.


  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor J Michael Dixon, Professor of Surgery & Consultant Surgeon.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

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