A breast lump is any area of thickening or distinct swelling that feels different from the surrounding breast tissue, and it can be a normal finding, a benign (non-cancerous) condition, or occasionally a sign of breast cancer.
Most breast lumps that people notice are not cancer — common causes include cysts, fibroadenomas, and normal hormonal changes in the breast tissue3. But because some lumps are cancerous, every new breast lump should be examined by a doctor1. The only way to know what a lump is, is to have it properly assessed.
Orientation Why you might be reading about this
You have probably found something in your breast that you did not notice before, or a routine check has raised a question. Most lumps turn out to be benign, but the wait between finding a lump and being seen is often the most anxious part — and that is also the part that is easiest to shorten. This page explains what a breast lump is, what it can be, and what a sensible next step looks like.
Related terms: Fibroadenoma · Breast cyst · DCIS · Invasive ductal carcinoma · Triple assessment · One-stop breast clinic
Definition What a breast lump can be
The breast is made up of lobules (the glands that produce milk), ducts (the channels that carry it), fatty tissue, and fibrous tissue. A lump can arise from any of these. The most common causes in adults are:
- Cysts — fluid-filled sacs, usually smooth and mobile, often tender and more noticeable around the menstrual cycle. Most cysts do not need treatment; if they are painful, they can be drained with a fine needle.
- Fibroadenomas — smooth, firm, rubbery lumps of glandular tissue, most common in women in their twenties and thirties. They are benign and usually left alone unless they grow or cause discomfort.
- Normal nodularity — in many people, breast tissue is naturally lumpy, and this can feel more pronounced at certain points in the menstrual cycle.
- Fat necrosis — a benign area of damaged fatty tissue, sometimes after an injury or surgery, which can feel firm and be mistaken for a tumour.
- Breast cancer — which can feel like a hard, irregular lump that does not move easily under the skin, but can also feel subtle, soft, or rounded. No lump should be assumed to be cancer on examination alone, and no lump should be assumed to be benign on examination alone.
Diagnosis How a breast lump is assessed
The standard assessment in the UK is called triple assessment and usually takes place at a one-stop breast clinic2. It has three components, done in the same visit where possible:
- Clinical examination by a breast specialist.
- Imaging — ultrasound for most patients under 35, and ultrasound plus mammogram for most aged 35 and over2.
- Biopsy — a small tissue sample taken under local anaesthetic, if imaging or examination warrants it2.
Imaging results are usually available on the day. Biopsy results typically take a few working days because the tissue has to be processed and examined under a microscope.
Why imaging matters What the lump feels like is not enough
Online information often describes cancerous lumps as hard, painless, and fixed, and benign lumps as soft, mobile, and tender. These descriptions are a rough generalisation and not a reliable guide. Some cancers are soft and mobile; some cysts are hard. The only way to know what a lump is, is to have it imaged and, where indicated, biopsied.
Next steps What to do next
Any new breast lump should be seen by a clinician — start with your GP. In the UK, a GP who is concerned about a breast lump will refer you on the urgent suspected cancer referral, with diagnosis or rule-out aimed within the NHS 28-day Faster Diagnosis Standard to an NHS breast clinic1, or you can arrange a private appointment directly. Either route gives you access to the same triple assessment. GPs typically make an urgent suspected cancer referral for an unexplained breast lump in anyone aged 30 or over; under 30, a non-urgent referral is often appropriate, though urgent referral can still be made if features are concerning. GPs typically make an urgent suspected cancer referral for an unexplained breast lump in anyone aged 30 or over; under 30, a non-urgent referral is often appropriate, though urgent referral can still be made if features are concerning.
You should seek advice sooner rather than later if, alongside a lump, you notice any of the following:
- A change in the shape, size, or outline of the breast.
- Changes to the skin — dimpling, puckering, or redness.
- Changes to the nipple — inversion, discharge (especially bloody), or a rash.
- A lump in the armpit.
A new lump in a man, in pregnancy, or in someone with a family history of breast or ovarian cancer should also be assessed promptly.
Read more about the one-stop breast clinic pathway.
Resources Further reading
- NHS — Breast lumps — patient overview of common causes and when to seek help.
- NHS — Breast cancer in women — what to look for and how breast changes are assessed.
- Breast Cancer Now — Breast lumps and benign breast conditions — patient-focused guide written by a UK breast cancer charity.
- Breastory: One-stop breast clinic · Symptoms assessment service