1. What is mucinous breast cancer?
Mucinous breast cancer is a rare type of invasive breast cancer. This means it has the potential to spread from the breast to other parts of the body.
It’s called mucinous because the cancer cells are surrounded by mucin. Mucin is a jelly-like (gelatinous) substance found naturally in the body.
Mucinous breast cancer is sometimes found alongside another type of breast cancer called invasive breast cancer (no special type). This may be referred to as “mixed” mucinous breast cancer.
Mucinous breast cancer found on its own, known as “pure” mucinous breast cancer, is less common.
“Pure” mucinous breast cancer generally has a better outlook (prognosis) than most other types of invasive breast cancer, including “mixed” mucinous breast cancer.
Mucinous breast cancer can occur at any age but is more commonly found in women over 60. Men can get mucinous breast cancer, but this is very rare.
2. Symptoms of mucinous breast cancer
As with most types of breast cancer, the symptoms of mucinous breast cancer include:
- A lump or thickening of the breast tissue
- A change of skin texture, such as puckering or dimpling
- A lump or swelling under the arm
- Changes to the nipple
- Discharge from the nipple
- A change in the size or shape of the breast
However, it can be found during routine breast screening before there are any symptoms.
3. Diagnosis
Mucinous breast cancer is diagnosed using a range of tests. These may include:
- A
- An
- A of the breast and sometimes lymph nodes
- A of the breast and sometimes lymph nodes
4. Treatment
As with all types of breast cancer, the treatments you’re offered will depend on the features of the mucinous breast cancer, such as its:
Treatment aims to remove the cancer and reduce the risk of it coming back or spreading to other parts of the body.
Surgery
Surgery is usually the first treatment for mucinous breast cancer.
There are 2 main types of surgery:
- Breast-conserving surgery (also known as wide local excision or lumpectomy) – removal of the cancer with a margin (border) of normal breast tissue around it
- Mastectomy – removal of all the breast tissue, usually including the nipple area
The type of surgery recommended depends on:
- Where the cancer is in the breast
- The size of the cancer relative to the size of the breast
- Whether more than 1 area in the breast is affected
You may need more surgery if the margin of normal tissue surrounding the cancer that was removed during the first operation is not clear. This is to make sure all the cancer has been removed. In some cases, this second operation will be a mastectomy.
Most women who have a mastectomy will have the option to have breast reconstruction.
Surgery to the lymph nodes
Your treatment team will want to check if any of the lymph nodes (glands) under your arm contain cancer cells. This, along with other information about your breast cancer, helps them decide whether you will benefit from any additional treatment after surgery.
Mucinous breast cancer is less likely to spread to the lymph nodes than most other types of breast cancer. This is particularly the case if the cancer is small or if it’s “pure” mucinous breast cancer.
Other treatments
After surgery you may need other treatments. This is called adjuvant treatment and can include:
- Radiotherapy
- Hormone (endocrine) therapy
- Chemotherapy
- Targeted therapy
- Bisphosphonates
These treatments aim to reduce the risk of breast cancer returning in the same breast or spreading elsewhere in the body.
Which treatments are recommended will depend on your individual situation.
Some of these treatments can be given before surgery. This is known as neo-adjuvant or primary treatment.
Radiotherapy
Radiotherapy uses high energy x-rays to destroy cancer cells.
If you have breast-conserving surgery you’ll usually be offered radiotherapy to the breast.
Radiotherapy is sometimes given to the chest wall after a mastectomy.
Hormone (endocrine) therapy
Some breast cancers use oestrogen in the body to help them grow. These are known as oestrogen receptor positive or ER-positive breast cancers.
Hormone therapies block or stop the effect of oestrogen on breast cancer cells. Different hormone therapy drugs do this in different ways.
Hormone therapy will only be prescribed if your breast cancer is ER-positive.
Chemotherapy
Chemotherapy destroys cancer cells by affecting their ability to divide and grow.
In primary breast cancer, it’s given to reduce the risk of breast cancer returning or spreading.
Chemotherapy may be given on its own or alongside other treatments.
Targeted therapy
Targeted therapy can be used to treat mucinous breast cancer.
Targeted therapies are a group of drugs that block the growth and spread of cancer. They target and interfere with processes in the cells that help cancer grow.
The type of targeted therapy you are given will depend on the features of your breast cancer.
Targeted therapies are usually given in combination with chemotherapy or hormone therapy.
Your treatment team will discuss if you will be offered a targeted therapy as part of your treatment.
Bisphosphonates
Bisphosphonates are a group of drugs that can reduce the risk of breast cancer spreading in women who have been through the menopause.
Your treatment team can tell you if bisphosphonates would be suitable for you.
5. After treatment
You will continue to be monitored after your hospital-based treatments (such as surgery, chemotherapy or radiotherapy) finish. This is known as follow-up.
It can be difficult to know how your breast or scar should feel. The area around the scar may feel lumpy, numb or sensitive. This means you'll need to get to know how it looks and feels so you know what’s normal for you. This will help you to feel more confident about noticing changes and reporting them early to your GP or breast care nurse.
Having breast cancer in one breast means the risk of developing cancer in the other breast (a new primary breast cancer) is slightly higher than in someone who's never had breast cancer. Therefore it's important to be aware of any new changes to your breasts and to report these as soon as possible.
6. Further support
If you’ve been diagnosed with breast cancer, you might be feeling lonely or isolated. It’s completely natural to have these feelings.
You might find it helps to talk to someone who has been diagnosed with breast cancer. Find out about our Someone Like Me service below.
You can also visit our confidential online forum and talk to other people affected by breast cancer.
You can also speak to our nurses on our free helpline, below.
