Posted by Manuela Boyle on 1 March 2021

You may see these descriptions of the type of cancer in your report:
DCIS (Ductal Carcinoma in Situ). This is a cancer that is non-invasive. It stays inside the milk ducts.
LCIS (Lobular Carcinoma in Situ). This is a tumour that is an overgrowth of cells that stay inside the milk-making part of the breast called lobules. LCS is not a true cancer. It is a warning sign of an increase risk for developing an invasive cancer in the future in either breasts.
IDC (Invasive Ductal Carcinoma). This is a cancer that begins in the milk duct but has grown into the surrounding normal tissue inside the breast. This is the most common kind of cancer.
ILC (Invasive Lobular Carcinoma). This is a cancer that starts inside the milk-making glands (called lobules) but grows into the surrounding normal tissue inside the breast.

How different are the cancer cells from normal cells?
Grade is how different the cancer cells are from the normal cells. Experts compare the appearance of the cancer cells to the normal breast cells. Based on these comparisons, they give a grade to the cancer. Grade is different from stage.
There are three cancer grades:
Grade 1 (low grade or well differentiated). Grade 1 cancer cells look a bit different from normal cells. They are usually slow growing.
Grade 2 (intermediate/moderate grade or moderately differentiated). Grade 2 cancer cells do not look like normal cells. They are growing a little faster than normal.
Grade 3 (high grade or poorly differentiated). Grade 3 cancer cells look very differentiated from normal cells. They are fast growing.

How big is the cancer?
Medical specialists measure cancer in centimetres (cm). The size of the cancer is one of the factors that determines the stage and treatment of the breast cancer.
Size does not tell the whole story. All the cancer's characteristics are important. A small cancer can be fast growing while a large cancer may be slow-growing, or it could be the other way around.

HER2 Status
Your pathology report usually includes the cancer's HER2 status. The HER2 gene is responsible for making HER2 proteins. These proteins are receptors on breast cells. Under normal circumstances, HER2 receptors help control how a breast cells grows, divides, and repairs itself. In about 25% of breast cancers, the HER2 gene can become abnormal and make too many copies of itself (amplification of the HER2 gene). Amplified HER2 genes command breast cells to make too many receptors (overexpression of the HER2 protein). When this happens, the overexpressed HER2 receptors shout at (rather than talk to) the breast cells to grow and divide in an uncontrolled way. This can lead to the development of breast cancer.
Breast cancer that have amplified HER2 genes or that overexpress the HER2 protein are described in the pathology as being HER2-positive. HER2 positive breast cancers tend to grow faster and are more likely to spread and come back when compared with HER2-negative breast cancers. However, HER2-positive breast cancer can respond to targeted treatments that are designed to work against HER2-positive cancer cells.

EGFR Status.
The EGFR gene much like the HER2 gene can be overexpressed in some breast cancer cells and influence how cancer behave. Your pathology report may also contain information about EGFR overexpression.

Other genetic testing
Inherited cases of breast cancer are likely associated with abnormal genes. Two of the most common are abnormal versions of BRCA1 (BReast CAncer 1) and BRCA2 (BReast CAncer 2). According to the National Cancer Institute, women with an abnormal BRCA1 or BRCA2 have about a 60% risk of being diagnosed with breast cancer during their lifetime, compared to about 12% for women overall. Their risk of ovarian cancer is also increased.
Changes in other genes are also associated with breast cancer, though they are less common and don't seem to increase risk as much as the BRCA1 and BRCA2. Although abnormal BRCA1 and BRCA2 are considered rare, there are other abnormal genes associated with a higher-than-average risk of breast cancer that are even more rare and have not been studied as much as the BRCA genes. These include ATM, BRIP1, CHEK2, PALB2, PTEN, TP53 and others.

Author:Manuela Boyle
Tags:NewsEvidence Based ResearchMost PopularCancerBreast Cancer


  • The Institute for Functional Medicine
  • Society for Integrative Oncology
  • American Society of Clinical Oncology
  • Australian Traditional-Medicine Society
  • Naturopaths and Herbalists Association of Australia