Breast cancer
The most common cancer in women, in which cells in the breast grow abnormally. Most breast lumps are not cancer, and when breast cancer is found early it is very often treatable. Screening, prompt assessment of any change and modern treatment mean outcomes today are good for many people.
What it is
Breast cancer develops when cells in the breast — usually in the milk ducts or the milk-producing lobules — begin to grow in an uncontrolled way. It is the most common cancer in women, though men can develop it too. It often causes no symptoms early on, which is why screening mammography is offered to find it before it can be felt; when symptoms do appear, the commonest is a new, painless breast lump, along with changes such as a change in breast shape or size, skin dimpling or puckering, nipple change or discharge, or a lump in the armpit. It is important to keep this in perspective: most breast lumps and breast changes turn out to be benign, not cancer. Risk rises with age and is influenced by family history and certain inherited genes (such as BRCA1 and BRCA2), hormonal and reproductive factors, and lifestyle. Diagnosis is made not by a blood test but by examination, imaging (mammogram and ultrasound) and a biopsy of the tissue. Treatment is highly effective and tailored to the individual tumour — surgery, radiotherapy, hormone therapy, chemotherapy and targeted drugs — and when caught early, breast cancer is very often curable. Blood tumour markers such as CA 15-3 play only a supporting role in monitoring, not in making the diagnosis.
Key lab markers
- CA 15-3 — a monitoring marker in known breast cancer, followed over time; not used to screen or diagnose.
- CEA — sometimes followed alongside CA 15-3 during monitoring.
- Diagnosis is by imaging and biopsy — mammogram, ultrasound, MRI and tissue biopsy, not blood tests.
- Full blood count, liver and bone markers — may be checked to assess general health and monitor during treatment.
Symptoms
- A new lump or thickening in the breast or armpit (most are benign, but any new lump should be checked)
- A change in the size or shape of the breast
- Skin dimpling, puckering or an orange-peel texture
- Nipple change, inversion, or unusual discharge (especially bloodstained)
- Redness or a rash on or around the nipple
- Persistent breast or armpit discomfort
- Often no symptoms at all — found on screening
Related symptoms
When to discuss with a doctor
Any new or unusual breast change — a lump, a change in shape or skin, or a nipple change or discharge — deserves prompt assessment by a doctor, even though most such changes are not cancer. Attend breast screening when invited, as it can find cancer before it can be felt, when treatment is simplest and most effective. Be aware of a strong family history of breast or ovarian cancer, which may mean earlier or additional screening. Breast cancer is diagnosed by examination, imaging and biopsy — not by a blood test — and blood tumour markers like CA 15-3 are used only to help monitor known disease. Mediora.AI can show a CA 15-3 or CEA trend in context for someone under monitoring, but any breast lump or change needs specialist assessment; the diagnosis and care belong with your medical team.