Lumpectomy when there is more than one tumour

Finding more than one area of cancer in the same breast is not unusual, and it does not automatically mean you need a mastectomy. Doctors describe two broad patterns. Multifocal cancer means two or more tumours in the same area or quadrant of the breast, usually fairly close together. Multicentric cancer means tumours in different quadrants, further apart. Multifocal cancers can often be removed together in a single lumpectomy, provided the area removed is not too large for your breast and clear margins can be achieved. Multicentric cancers were traditionally treated with mastectomy, but newer research has shown that some women with two or three separate tumours can safely have breast-conserving surgery, removing each area through one or more cuts, followed by radiotherapy. Whether this is suitable depends on how many tumours there are, how far apart they are, their total size compared with your breast, whether an MRI shows further hidden areas, whether each area can be removed with clear margins, and whether you can have radiotherapy afterwards. Treatment before surgery with chemotherapy, HER2-targeted treatment or hormone therapy can sometimes shrink the tumours enough to make breast conservation possible. A multidisciplinary team review of the scans and biopsies is the best way to decide.

Multifocal is often suitable

Tumours close together can usually be removed in one piece of tissue.

Multicentric needs more careful selection

Some women with two or three separate areas can still keep the breast.

Imaging and biopsy guide the choice

Your team needs to know exactly how many areas there are and where.

Breast conservation with several tumours is possible for some women, but there are trade-offs to understand.

A second operation is more likely

With more areas to remove, the chance that one margin is not clear goes up.

Appearance may be affected more

Removing tissue from more than one place can change the shape or leave dents, though oncoplastic techniques help.

MRI can find areas that turn out not to be cancer

Extra biopsies may be needed, and these can delay surgery a little.

Evidence for multicentric conservation is newer

Studies are encouraging, but fewer and shorter than for single tumours.

What this page cannot tell you

It cannot say whether your tumours can be safely removed while keeping your breast. That needs your scans, biopsies and a team review.

Surgery is only one part of treatment, and the steps afterwards matter just as much when there were several tumours.

Radiotherapy to the whole breast

Radiotherapy is an essential part of breast conservation. A boost to tumour areas may also be recommended.

Medicines based on the tumours' biology

Each tumour's receptors are checked. If they differ, your team plans treatment to cover all of them.

Staging for size

For staging, doctors usually use the size of the largest tumour rather than adding the sizes together.