Scientists in Manchester have identified a way to potentially predict which patients with an early form of breast cancer will experience disease progression.
Ductal carcinoma in situ (DCIS) is a precursor of breast cancer where the cancerous cells are contained within the milk-making ducts. Without treatment, commonly a combination of breast-conserving surgery and radiotherapy, up to a half of patients will have their disease come back, either as DCIS or as invasive breast cancer.
It is currently not possible to predict which cases will progress; so all women are offered radical treatment, potentially unnecessarily.
A recent study by researchers from the Manchester Cancer Research Centre, published in the journal Annals of Oncology, has explored potential subtypes of DCIS and whether these subtypes relate to disease recurrence.
Professor Nigel Bundred, from The University of Manchester and University Hospital of South Manchester NHS Foundation Trust, who led the study, said: “We know that different subtypes of invasive breast cancer have different levels of disease recurrence. We wanted to investigate similar subtypes in DCIS to see if they had predictive power.”
The team looked at tumour samples taken from 314 patients diagnosed with DCIS. By using a range of tissue stains, they were able to assess levels of oestrogen receptor (ER), progesterone receptor (PR) and HER2 - human epidermal growth factor - in order to divide the samples into four subtypes.
They found that patients whose tumours tested positive for ER and PR, but negative for HER2, were less likely to see their cancer come back. Other subtypes were significantly more likely to recur as invasive breast cancer.
Types of breast cancer
Ductal carcinoma in situ (DCIS)
This is the earliest form of breast cancer. In DCIS, cancer cells are in the ducts of the breast, but they haven’t started to spread into the surrounding breast tissue. DCIS shows up on a mammogram and is usually diagnosed when women go for breast screening.
Lobular carcinoma in situ (LCIS)
LCIS isn’t breast cancer. In LCIS, there are changes to the cells lining the lobes, which slightly increases the risk of developing breast cancer later in life. Most women with LCIS never develop breast cancer. It’s monitored with regular breast screening and mammograms.
Triple Negative Breast Cancer
Triple negative breast cancer means that the cells in the tumor are negative for progesterone, estrogen, and HER2/neu receptors.
Inflammatory Breast Cancer
Inflammatory breast cancer is a less common form of breast cancer that may not develop a tumor and often affects the skin.
Metastatic Breast Cancer
Metastatic breast cancer is cancer that has spread beyond the breast, sometimes into the lungs, bones, or brain.
Breast Cancer during Pregnancy
Women who are diagnosed with breast cancer during pregnancy may face tremendous additional strain due to concern for the safety of the unborn child.
Invasive breast cancer
Most breast cancers are invasive. This means the cancer cells have spread outside the lining of the ducts or lobules into surrounding breast tissue.
Invasive ductal breast cancer
Most invasive breast cancers (80%) are this type.
Invasive lobular breast cancer
About 1 in 10 (10%) of invasive breast cancers are lobular. It can sometimes be difficult to diagnose on a mammogram. Doctors do tests on the cancer to help decide which treatments are best for you. They look at whether the cells have receptors (proteins) for hormones or a protein called HER2 (HER2 positive breast cancer). Breast cancer that has no receptors is called triple negative breast cancer.
There are some uncommon and rare types of invasive breast cancer.
“We regularly measure ER levels in patients with DCIS, but our findings suggest that the additional information from testing for HER2, which is routine for patients with more advanced disease, could allow us to better identify those most at risk of invasive relapse. These tests are cheap and easy to carry out and could help some patients avoid unnecessary treatment,” added Professor Bundred.
Paper entitled “Molecular Phenotypes of DCIS predict overall and invasive recurrence” Williams et al. (2015) Annals of Oncology
University of Manchester
Annals of Oncology