Does having a mastectomy affect how long you live after breast cancer treatment?
A new study has found that women who choose to have treatment for breast cancer but keep their breast are more likely to live for longer, and live for longer without their cancer coming back, than women who have their breast removed.
BMJ Group News
What do we know already?
Breast cancer is the most common cancer in women. It accounts for around 33 in every 100 cancers diagnosed in women. About 48,000 women are diagnosed with breast cancer in the UK each year.
Women with breast cancer face a number of decisions about their treatment. The treatment options available depend on a number of things, including what ‘stage’ cancer you have.
The stage of a breast cancer means the size of the tumour, and where it grows in the breast or in the body. For example stage 1 or 2 breast cancers are generally smaller and almost always grow inside the breast, or sometimes under the armpits. These are generally called early-stage breast cancers.
Treatments for early-stage breast cancer include an operation to remove the entire breast that has cancer. This is called a mastectomy. Another treatment is breast-conserving surgery. This means an operation to remove only the part of the breast that has the cancer, plus a small amount of healthy tissue around the cancer. This is sometimes called a lumpectomy.
In studies, women who had mastectomies haven’t lived for very much longer than women who had breast-conserving surgery. But we’re still not sure if the same can be said of women in the real world. The studies that have looked at this have lasted only a few years, whereas we would need longer studies to assess the difference between the treatments.
This study looked at 112,154 women who had either mastectomies or breast-conserving surgery for stage 1 or 2 breast cancer between 1990 and 2004. The researchers monitored the women for an average of nine years. They compared how long the two groups of women lived, and, if their cancer came back, how much time passed before it came back.
What does the new study say?
Overall 31,416 women died during the study. In 39 in every 100 women who died, the cause was breast cancer.
When the researchers compared the two groups, they found that women who had breast-conserving surgery were more likely to live for longer than women who had a mastectomy. They were also more likely to live for longer without their breast cancer coming back than women who had a mastectomy.
The biggest benefit was in women who were older than 50 and who had a type of breast cancer called hormone-receptor positive breast cancer.
How reliable is the research?
This is a large study that followed women for several years after they had breast cancer treatment, so the study should be reliable. This means we can be reasonably confident that the results seen in previous studies do relate to the real world.
What does this mean for me?
All breast cancer treatments have advantages and disadvantages, and can affect how likely you are to live, how likely your cancer is to come back, and your feelings about how your breasts look. This study suggests that you have a better chance of living for longer if you have an operation to remove a lump from your breast than if you have your breast removed.