HER2-Positive vs Triple-Negative Breast Cancer

HER2-positive vs triple-negative breast cancer: at a glance

How HER2-positive and triple-negative breast cancer compare, using NHS inform, NICE and WHO information.
Feature	HER2-positive	Triple-negative
What it means NHS inform (Scotland): Breast cancer in women	The cancer cells have too much HER2 protein on their surface	No receptors for HER2, oestrogen or progesterone
How it is found NICE NG101: Assessment of tumour profile and genetic testing	HER2 is tested on every invasive breast cancer at diagnosis; the result is positive	ER, PR and HER2 are tested at diagnosis; all three are negative
How common, and gene links NHS inform (Scotland): Breast cancer in women	About 1 in 5 breast cancers (15 to 20%)	Most breast cancers caused by a BRCA1 gene change are triple-negative
Targeted treatment World Health Organization: Breast cancer fact sheet	Targeted drugs such as trastuzumab can be used, combined with chemotherapy	No HER2 target; the WHO lists it among the more aggressive subtypes
Hormone therapy World Health Organization: Breast cancer fact sheet	May help if the cancer also has oestrogen or progesterone receptors	Hormone receptor negative, so chemotherapy is needed unless the cancer is very small
Before surgery (NICE) NICE NG101: Early and locally advanced breast cancer	Chemotherapy where needed; pertuzumab with trastuzumab for some	Chemotherapy with a platinum, a taxane and an anthracycline where needed; pembrolizumab for some
After surgery (NICE) NICE NG101: Early and locally advanced breast cancer	Trastuzumab every 3 weeks for 1 year for most; other anti-HER2 drugs for some	Pembrolizumab continued for some; olaparib for some with a BRCA gene change

Each row links to the NHS, NICE or WHO page it comes from. On a small screen, scroll the table sideways.

Key takeaways

HER2-positive cancer cells have too much HER2 protein. About 1 in 5 breast cancers are HER2-positive. (NHS inform (Scotland): Breast cancer in women)
Triple-negative breast cancer has no receptors for HER2, oestrogen or progesterone. (NHS inform (Scotland): Breast cancer in women)
NICE says ER, PR and HER2 status should be checked on every invasive breast cancer at diagnosis. (NICE NG101: Assessment of tumour profile and genetic testing)
NICE recommends offering BRCA1 and BRCA2 genetic testing to women under 50 with triple-negative breast cancer, even without a family history. (NICE NG101: Genetic testing)
NICE says decisions about medicines are based on a specialist team’s assessment and made with the person after discussing the risks and benefits. (NICE NG101: Systemic anticancer therapy planning)

What do HER2-positive and triple-negative mean?

Breast cancer cells may have receptors on their surface. Hormones such as oestrogen can attach to these receptors and encourage the cells to grow. Some breast cancer cells also have too much of a protein called HER2, which encourages them to divide and grow. This is HER2-positive breast cancer.

Triple-negative breast cancer has no receptors for HER2 or for the hormones oestrogen and progesterone. NICE defines it as a cancer where ER, PR and HER2 have each been scored as negative.

A doctor called a pathologist tests cancer cells taken during a biopsy or surgery for these receptors, and the results help decide the most effective treatment.

Sources: NHS inform (Scotland): Breast cancer in women; NICE NG101: Terms used – triple-negative breast cancer

How is HER2-positive breast cancer treated?

Targeted drugs lock on to the HER2 protein, which helps stop the cancer cells dividing and growing. The WHO says targeted drugs such as trastuzumab are combined with chemotherapy to make them effective.

NICE recommends trastuzumab after surgery for HER2-positive invasive cancers, given every 3 weeks for 1 year alongside other treatments as needed; for the smallest cancers it is considered rather than routinely offered. Because trastuzumab can cause heart problems, NICE says it should be used with caution in people with certain heart conditions.

Sources: NHS inform (Scotland): Breast cancer in women; World Health Organization: Breast cancer fact sheet; NICE NG101: HER2-positive breast cancer

How is triple-negative breast cancer treated?

The WHO says cancers without oestrogen or progesterone receptors need to be treated with chemotherapy unless the cancer is very small, and that today’s chemotherapy is very effective at reducing the chance of the cancer spreading or coming back.

When chemotherapy is given before surgery, NICE recommends a regimen that contains a platinum drug, a taxane and an anthracycline. NICE also recommends pembrolizumab, an immunotherapy, as an option with chemotherapy before surgery and then on its own afterwards, for some people at high risk of the cancer coming back.

Sources: World Health Organization: Breast cancer fact sheet; NICE NG101: Triple-negative (ER/PR/HER2-negative) breast cancer

Why is genetic testing offered for triple-negative breast cancer?

NHS inform says people with triple-negative breast cancer may be offered genetic testing, even without a family history, and that most breast cancers caused by a change in the BRCA1 gene are triple-negative. NICE recommends offering BRCA1 and BRCA2 testing to women under 50 with triple-negative breast cancer.

For adults with an inherited BRCA1 or BRCA2 change and HER2-negative early breast cancer at high risk, NICE recommends olaparib as an option after chemotherapy.

Sources: NHS inform (Scotland): Breast cancer in women; NICE NG101: Genetic testing; NICE NG101: Triple-negative (ER/PR/HER2-negative) breast cancer

Frequently asked questions

Is triple-negative breast cancer more aggressive than HER2-positive?

The WHO describes triple-negative breast cancer as one of the more aggressive subtypes, and says HER2-positive cancers can be treated with targeted drugs such as trastuzumab. The WHO says treatment depends on the subtype and how far the cancer has spread, so a breast team is best placed to explain what a diagnosis means for each person.

Source: World Health Organization: Breast cancer fact sheet

How common is HER2-positive breast cancer?

NHS inform says about 1 in 5 breast cancers (15 to 20%) are HER2-positive. The extra HER2 protein encourages the cancer cells to divide and grow, and specific targeted drugs that lock on to the HER2 protein are used to treat it.

Source: NHS inform (Scotland): Breast cancer in women

Can triple-negative breast cancer be treated with hormone therapy?

Hormone (endocrine) therapies such as tamoxifen or aromatase inhibitors are likely to work for cancers that have oestrogen or progesterone receptors. Triple-negative breast cancer does not have these receptors. The WHO says hormone receptor negative cancers need to be treated with chemotherapy unless the cancer is very small.

Source: World Health Organization: Breast cancer fact sheet

What is trastuzumab?

Trastuzumab is a targeted medicine for HER2-positive breast cancer. NICE recommends it after surgery for most HER2-positive invasive cancers, given every 3 weeks for 1 year alongside surgery, chemotherapy, hormone therapy and radiotherapy as appropriate. NICE says it should be used with caution in people with some heart conditions.

Source: NICE NG101: HER2-positive breast cancer

Does triple-negative breast cancer run in families?

It can be linked to inherited genes. NHS inform says most breast cancers caused by a change in the BRCA1 gene are triple-negative, and that people with triple-negative breast cancer may be offered genetic testing even with no family history. Anyone worried about breast cancer in their family can ask a GP about a genetics clinic referral.

Source: NHS inform (Scotland): Breast cancer in women

Can a breast cancer be HER2-positive and hormone receptor positive?

Yes. NICE guidance refers to hormone receptor-positive, HER2-positive breast cancer, and recommends neratinib as an option for extended treatment of this type in some people who finished trastuzumab-based treatment less than a year ago.

Source: NICE NG101: HER2-positive breast cancer

Sources and references

This page is general information, not medical advice. A GP or doctor can advise on your own situation. Source links do not imply endorsement by the NHS or another organisation. See our editorial policy.

HER2-positive vs triple-negative breast cancer