Breast cancer and delays in diagnosis: A guide for patients

6 Min Read

Paul Sankey - Enable Law

In this guide, medical negligence partner Paul Sankey looks at what can go wrong when breast cancer diagnosis is missed or delayed, identifies the key warning signs of breast cancer, and looks at your GP’s role in diagnosing breast cancer:

Breast Cancer: Stories of 3 Women

Sheila was 35 when she went to her GP with a new lump on her left breast. Her GP examined her breasts but did not think the lump was suspicious. He reassured her. She went back 2 months later with the same lump. Again her GP reassured her. A year later the lump was bigger. She went back to her surgery and saw a different GP. The doctor referred her urgently to hospital and she was diagnosed with an aggressive breast cancer. Unfortunately the delay in diagnosis of breast cancer had allowed the disease to spread. She was told she was unlikely to survive her cancer. She recovered damages against the first GP. The award helped her when she was not able to work and she was able to pay for the care at home she needed.

Pat was 52. She noticed discharge from a nipple. Her GP referred her urgently to the local breast clinic. She saw a breast surgeon who examined her breast and arranged a mammogram. The mammogram was done. She was told it showed nothing abnormal. 2 years later she noticed a large lump in her breast. This time she was diagnosed with advanced breast cancer. Sadly she died. A review of the mammogram showed it had been misinterpreted. Her husband succeeded in a claim against the hospital.

Jane was 41. She noticed a lump in her right breast. Her GP referred her to hospital. She was seen within a week. A breast surgeon thought the lump was suspicious and arranged a mammogram. The mammogram showed a lesion which the radiologist thought looked like cancer. She then had an ultrasound-guided biopsy to remove some tissue. A pathologist examined the tissue under a microscope. She reported it as benign – not cancer. 18 months later she was diagnosed with advanced breast cancer. On review the tissue sample was found to have been wrongly interpreted. It had in fact showed cancer. She had to have both breasts removed. She underwent chemotherapy. She also took action against her hospital and succeeded in a claim.

Delays in Diagnosis

In all 3 cases, there were avoidable delays in diagnosing breast cancer. All should have been diagnosed and treated earlier. The most common medical mistakes are:

1. GPs failing to refer when they should;
2. Wrongly interpreting mammograms, ultrasound scans or MRI scans. This may also happen during screening; and
3. Mistakes in looking at tissue under the microscope (biopsy).

When You Should See Your GP

Cancer Research UK advises you to see your doctor if you have:
• a change in a breast’s size, shape or feel;
• a new lump or thickening in a breast or armpit;
• skin changes – puckering, dimpling, rash or redness;
• fluid leaking from a nipple in women who are not pregnant or breastfeeding;
• changes in a nipple; or
• breast pain.
They advise that your symptoms are probably not cancer but it is important to get a doctor to check.

Avoidable Delays – Legal Claim

If there your cancer has been diagnosed late because of an avoidable error with breast cancer screening and you have been harmed as a result, you may be entitled to damages. You would need to prove:
1. A negligent mistake causing delay;
2. Harm – that your condition has worsened.

The most common delays in diagnosis are either when GPs fail to refer patients to specialists or when investigations are misinterpreted.

When GPs should refer

Guidelines by NICE (National Institute for Clinical Excellence) help GPs to know when they should refer patients for investigation. They should suspect cancer and make urgent referrals for patients to be seen within 2 weeks where:

• Patients aged 30 or more have an unexplained breast lump with or without pain; or
• Patients are aged 50 and over and have any of these symptoms in one nipple only:
o Discharge;
o Retraction (ie where the nipple sinks into the breast or points inwards rather than outwards); or
o Other changes of concern.

GPs should also refer patients with:
• Skin changes suggesting breast cancer (puckering, dimpling, a rash or redness) including the skin changing texture; or
• An unexplained lump in the armpit where the patient is aged 30 or more.

Most breast lumps are not cancer. But some are. GPs may not be able to tell. It is important that they refer when they should.


At a breast clinic you may have various investigations. These include:

1. Examination by a breast surgeon;
2. Radiology in the form of a mammogram and ultrasound scan. Both are ways of looking at breast tissue to spot anything abnormal. Sometime MRI scans may be done.
3. Biopsy. This is when a pathologist looks at tissue from your breast under a microscope. There different ways of obtaining the tissue including fine needle aspiration, needle biopsy, punch biopsy and wire guided excision biopsy.

Normally to diagnose breast cancer the 3 forms of investigation must all suggest cancer.

How Cancer Progresses

Doctors class the state of cancer by its Stage. Breast cancer is classed as Stage 1 to 4. Its stage depends on the size and extent of the tumour, whether it has spread to the lymph and whether it has spread elsewhere in the body. They refer to each of these a T (tumour size and extent), N (lymph node involvement) and M (metastasis – distant spread).

Cancers are all different. There are many different types of breast cancer. They develop at different rates. Delays may not have caused measurable harm if the cancer has not progressed to a new stage. If the Stage has changed, the harm may be either that your chance of cure is lower or that you need more treatment.

Where a Mistake Has Been Made

If there has been a delay in diagnosing cancer and you have suffered harm you may be entitled to claim damages. To succeed you need to show:
1. An avoidable, negligent mistake;
2. Harm – that the cancer has progressed.

Our specialist lawyers have experience of acting for patients on complex and sensitive claims. If you would like advice please telephone 0800 044 8488.