Breast lumps: causes, what happens at the clinic and when to worry

The NHS says lumps in the breasts can have many causes. They are often caused by something harmless such as a non-cancerous tissue growth (fibroadenoma) or a build-up of fluid (breast cyst), but sometimes a breast lump can be a sign of breast cancer. It stresses that you should not try to work out the cause yourself and should always see a GP.

The NHS says to see a GP if you notice a lump in the breast or armpit or any unusual change, such as the nipple turning inwards, dimpled skin or bloodstained nipple discharge. Its breast cancer symptoms page adds a change in the size or shape of a breast, a change in the colour of the skin (which may look darker on black or brown skin and red on white skin), swelling in the chest or armpit and a rash on the nipple that may look like eczema.

The NHS says breast pain by itself is unlikely to be a symptom of cancer; it is usually linked to periods, beginning up to 2 weeks before a period and easing after it, feeling dull, heavy or aching and affecting both breasts. Other causes include injuries or sprains of the neck, shoulder or back, medicines such as the contraceptive pill and some antidepressants, mastitis or a breast abscess, pregnancy and menopausal hormone changes.

It advises an urgent GP appointment or NHS 111 if breast pain comes with a very high temperature or feeling hot, cold or shivery, any part of the breast is red, hot or swollen, there is a hard lump that does not move around, nipple discharge streaked with blood, a change in breast shape, dimpled skin like orange peel, a rash around the nipple or a nipple that has sunk into the breast.

The NHS says the GP will look at and examine your breasts. If they are not sure what is causing the lump they will refer you to a hospital or breast clinic for further tests. For the examination you undress from the waist up behind a screen, and you can have a friend, family member or another member of staff in the room. The GP may ask about previous breast screening and any family history of breast cancer.

NICE sets referral rules for GPs: a suspected cancer pathway referral for people aged 30 and over with an unexplained breast lump with or without pain, and for people aged 50 and over with discharge, retraction or other concerning changes in one nipple only. It says to consider that pathway for skin changes that suggest breast cancer or an unexplained armpit lump in people aged 30 and over, and to consider non-urgent referral for people under 30 with an unexplained lump.

The NHS says that at the hospital or breast clinic you may have a breast examination, a scan (usually a mammogram, which is a breast X-ray, or an ultrasound) and a biopsy, where a needle is inserted into the lump to remove some cells for testing. These tests are often done in the same visit and you will usually be told results the same day, although you may wait about a week for biopsy results. It says these tests usually show a lump is not cancer.

The NHS says treatment for a breast lump depends on the cause and that most lumps are harmless and may go away without treatment. Fibroadenomas and cysts are the two examples it gives, and it directs people to Breast Cancer Now for more on each. If a lump is found to be cancer, treatment is planned by a specialist team, as described on the breast cancer page.

The NHS says it is important to check your breasts regularly so you know what is normal for you, making it easier to notice any change in size, look or feel. There is no single technique prescribed on the pages reviewed here; the point is familiarity. If you notice something new, do not wait for the next period or the next screening invitation.

A GP referral to an NHS breast clinic is the usual route. Private breast clinics can offer examination, imaging and biopsy on one visit and may be quicker. Whichever you choose, ask how and when results will be given, who will arrange follow-up if something is found, and make sure your GP is informed of the outcome.