Male breast cancer: symptoms, causes, diagnosis and treatment

The NHS lists the main symptoms of breast cancer in men as a lump or swelling in the chest or armpit, liquid leaking from the nipples (which may have blood in it), changes in the size or shape of either side of the chest, sores or ulcers on the chest, and a change in the shape or look of the nipple, such as turning inwards (an inverted nipple) or a rash on it that may look like eczema.

Cancer Research UK gives a similar list and adds that the breast lump is often painless and that swelling of the breast (gynaecomastia) can be a sign. It says if you have any of these symptoms it is important to go to your GP straight away, because finding a cancer early gives the best chance of successful treatment.

The NHS adds that it is important to check your chest regularly so you know what is normal for you, which makes it easier to notice changes in size, look or feel. It also stresses that some of these symptoms, including lumps, are common and can be caused by other conditions, and that having them does not definitely mean you have breast cancer.

• A lump or swelling in the chest or armpit (often painless).

• Nipple discharge, which may contain blood.

• A nipple pulled into the breast (inverted or retracted).

• A rash on or around the nipple, which may look like eczema.

• A sore or ulcer on the chest.

• A change in the size or shape of either side of the chest.

The NHS says to see a GP if you have a lump or swelling in your chest or armpit, nipple discharge from either nipple, or any changes in your chest or nipples that are not normal for you. The GP will ask about your symptoms, any breast screening you have had before and whether anyone in your family has had breast cancer, and may examine your chest. You will need to undress from the waist up behind a screen, and you can have a friend, family member or another member of staff in the room if you want.

If the GP thinks your symptoms could be cancer, the NHS says you may get an urgent referral for more tests or to see a specialist in hospital. It stresses that this does not definitely mean you have cancer.

The NHS explains that breast cancer is cancer that starts in the breast tissue, which everyone has in their chest, and that anyone can get it; it is rare in men. Cancer Research UK says men have breast tissue around the nipple area and can develop breast cancer.

The most common type in both women and men is invasive breast cancer of no special type (NST), sometimes called invasive ductal carcinoma NST. Cancer Research UK says men can also develop rarer types, which are very rare, including ductal carcinoma in situ (DCIS), invasive lobular cancer and Paget's disease of the breast. Trans women and non-binary people assigned male at birth can also develop breast cancer.

The NHS says how serious breast cancer is depends on how big it is, whether it has spread, and your general health. If breast cancer spreads to other parts of the body it is called secondary breast cancer.

Anyone can get breast cancer and it is not always clear what causes it. The NHS lists these things that make men more likely to get it: being over 60, having other people in the family who have had breast or ovarian cancer (you may have inherited a faulty gene such as a BRCA gene), having had radiotherapy to the chest before, a condition that affected or damaged the testicles (such as undescended testicles or mumps as an adult), surgery to remove one or both testicles, and working in a hot environment such as a steel works.

Higher levels of the hormone oestrogen may also raise risk. The NHS says this may be more likely with long-term liver damage such as cirrhosis, with obesity or being overweight, or with Klinefelter syndrome. Cancer Research UK also lists thyroid problems and the use of prohibited drugs such as marijuana among causes of high oestrogen levels, and says Klinefelter syndrome, a rare condition in which a man is born with an extra X chromosome, increases risk but does not mean you will definitely get breast cancer.

The NHS says many breast cancers are linked to lifestyle, such as smoking, and that you cannot always prevent breast cancer but can try to cut down on alcohol (avoiding more than 14 units a week), lose weight if overweight and try to quit smoking. If close relatives have had breast or ovarian cancer, you may be eligible for an NHS genetic test; speak to a GP, who may refer you to a specialist breast or genetics clinic.

The NHS says you may be referred to a breast clinic where tests can include an examination of your chest, a mammogram, an ultrasound and a biopsy, usually using a needle, to test for breast cancer and look for certain proteins in the cancer cells that help decide which treatments are best. You may not need all of them, and you will usually have all the tests you need in one visit. Some results are available that day, while biopsy results can take several weeks.

Cancer Research UK says you usually have an ultrasound scan of the breast and the lymph nodes under the arm, and may also have a mammogram. If these show an area that could be cancer, a biopsy may be taken. If breast cancer is found, you may have more tests to see whether it has spread, such as an MRI scan, a bone scan or a CT scan. The NHS lists a chest X-ray, scans and blood tests, and says the results show how far the cancer has spread, what type it is and whether it has been caused by certain gene changes.

If you are told you have breast cancer, the NHS says you will be helped by a team of specialists, including a clinical nurse specialist who is your main point of contact.

The NHS says treatment depends on the size and type of breast cancer, where it is, whether it has spread and your general health. The main treatment is usually surgery, and you may also have chemotherapy, radiotherapy, hormone therapy and targeted medicines. Cancer Research UK adds that grade, hormone-receptor status and other medical conditions are also taken into account.

Surgery: the NHS says removing the whole breast and nipple (mastectomy) is the most common operation for breast cancer in men and usually involves removing lymph nodes in the armpit. Cancer Research UK explains that most men do not have a lot of breast tissue, so it is not usually possible to leave any behind, and that the surgeon may remove some armpit nodes or check the nodes closest to the breast with a sentinel node biopsy. Removing just the cancer and some surrounding tissue may sometimes be possible, which may mean the nipple does not need to be removed.

Afterwards, radiotherapy may lower the risk of the cancer coming back, and chemotherapy may be given before surgery to shrink the cancer or after it to lower the chance of recurrence. Cancer Research UK says that for hormone receptor positive cancers you usually have hormone therapy for at least 5 years, most commonly tamoxifen, and that targeted drugs such as trastuzumab (Herceptin) may be used if cancer cells have certain receptors.

If you have had a nipple removed, the NHS says you may choose to have a new nipple made, using skin from another part of the body or by tattooing; stick-on nipples are another option. Cancer Research UK says to wait a few months after the mastectomy for swelling to settle.

The NHS says you will have regular check-ups during and after treatment, with tests and scans, and that you should talk to your specialists about symptoms or side effects you are worried about without waiting for your next check-up. Cancer Research UK says the frequency of check-ups depends on your individual situation.

If breast cancer has spread (secondary, advanced or metastatic breast cancer), treatment may focus on managing symptoms and helping you feel better, and Cancer Research UK says doctors may recommend chemotherapy, hormone therapy, targeted drugs, radiotherapy or a combination.

Because male breast cancer is rare, Cancer Research UK notes you are likely to be treated in a large, specialist hospital where your consultant may know other men with breast cancer to talk to. The NHS lists national charities that offer information and support, including Breast Cancer Now, Macmillan Cancer Support and Cancer Research UK. Many breast cancer trials have recruited only women, but Cancer Research UK says increasingly trials are recruiting men too.

Not every lump or swelling in a man's chest is breast cancer. The NHS says lumps are common and can be caused by other conditions. Cancer Research UK lists swelling of the breast (gynaecomastia) among the symptoms of breast cancer in men, so breast enlargement is a reason to have the chest examined rather than assume it is harmless.

A GP or breast clinic can tell the difference with an examination and, when needed, imaging and a biopsy. Do not wait for a lump to grow or hurt before getting it checked: the NHS says that if your symptoms are caused by cancer, finding it early may mean it is easier to treat.

On the NHS the route is through a GP, who can refer you to a breast clinic where examination, imaging and biopsy are usually done in one visit. Treatment is planned by a specialist team with a clinical nurse specialist as your main contact. NHS genetic testing may be offered if close relatives have had breast or ovarian cancer.

Private breast clinics and consultants can see men, offer imaging and biopsy and arrange treatment, but the treatments and the specialist team approach are the same. Ask who will coordinate your care, how and when results will be given, and how follow-up will work.