Breast lump: what to do and which tests you need

I have found a lump in my breast: what should I do?

The right approach comes down to two rules: don't panic, because the vast majority of breast lumps are not cancer, and don't wait, because only a medical examination can confirm this.

Make an appointment with your gynaecologist or GP. If you are having periods, note the date you found it: a lump linked to your cycle may shrink after your period, but a lump that persists beyond that must be investigated. The diagnosis and treatment of breast tumours fall within gynaecological oncology and breast medicine.

Do not wait for your next screening mammogram: a lump is a symptom, and it needs diagnostic tests, not just routine screening.

What causes a lump in the breast?

The causes vary greatly with age:

These pointers do not allow you to diagnose yourself: a "typical" fibroadenoma may need a biopsy, and a cancer can be mobile and smooth. That is why imaging matters. To find out more, see our articles on fibrocystic breast changes and breast pain while breastfeeding.

What happens at the appointment for a breast lump?

The doctor asks when you found the lump, how it changes over your cycle, whether there is pain or nipple discharge, about any hormonal treatments and any family history of breast or ovarian cancer. They then examine both breasts and both armpits, sitting up and then lying down.

They look for signs pointing to a benign lesion (well-defined, mobile, rubbery lump) or signs that call for prompt tests (hard, fixed lump, puckering of the skin or nipple, orange-peel skin, hard lymph node in the armpit). In every case, the clinical examination is followed by imaging.

What should I bring?

• your previous mammograms, ultrasound scans and reports, even old ones: comparing with earlier images is often decisive in showing that an abnormality is stable and therefore benign;
• a list of your treatments, particularly hormonal contraception or menopause treatment;
• information about breast, ovarian or prostate cancer in your family, with the age at diagnosis: this helps decide whether to offer a genetic counselling appointment.

What tests are needed for a breast lump?

Radiology societies recommend an approach based on age:

• Under 30: breast ultrasound is the first-line test. A mammogram is only added if the ultrasound shows a suspicious image.
• Between 30 and 39: ultrasound, with a mammogram depending on the situation.
• From 40: mammogram of both breasts and ultrasound of the area concerned.
• During pregnancy or breastfeeding: ultrasound first; a mammogram is still possible if needed.

A mammogram always looks at both breasts, which can detect another abnormality elsewhere. To find out what happens, read our article on mammography.

Understanding the ACR (BI-RADS) classification

The radiologist ends the report with an ACR category, which guides what happens next:

When is a breast biopsy or MRI needed?

When the image is classified ACR 4 or 5, or if doubt remains, a core needle biopsy is carried out. Under local anaesthetic, the radiologist takes several small samples of the lump with a needle, guided by ultrasound or mammography. It takes about twenty minutes and usually leaves only a small bruise. The result is sent to you via Doctolib or by post (by phone if it is urgent), then explained at an appointment.

Breast MRI is not a first-line test. It is useful in specific situations: when the examination and imaging do not match, very dense breasts, staging of a cancer before surgery, and surveillance of women at high genetic risk.

Fine needle aspiration is still useful to drain a large, painful cyst: relief is immediate.

What happens after the test results?

• Benign lesion (simple cyst, confirmed fibroadenoma): in most cases no treatment is needed. Clinical follow-up is offered, sometimes with a follow-up ultrasound. Surgery is considered if the lump grows, becomes bothersome or looks atypical.
• High-risk lesion (atypical hyperplasia, some papillary lesions): surgical removal of the area is often offered to check that no cancer is associated with it.
• Cancer: your case is discussed at a multidisciplinary team meeting, and a personalised treatment plan is offered to you. See our article on breast cancer.

When should I see a doctor quickly about a breast lump?

See a doctor within a few days if the lump comes with:

• puckering of the skin or a pulled-in nipple;
• red, thickened, orange-peel skin;
• bloody or clear discharge from one nipple only;
• a hard lymph node in the armpit;
• a lump that grows over a few weeks.

See a doctor the same day if a breast becomes red, hot and very painful with a fever, especially while breastfeeding, because an abscess needs prompt treatment; do not stop breastfeeding abruptly, as this increases the risk of an abscess (see breast pain while breastfeeding). For a breast appointment at the practice: book via Doctolib or by calling 01 43 79 59 79; the average waiting time for an appointment is one week to 10 days, except during holiday periods.

Frequently asked questions

General information article: it does not replace a medical consultation. In an emergency, call 15 or 112 in France, or your local emergency number.