How Oncologists Are Changing the Way Breast Cancer Is Ranked
For years now, breast cancer has been ranked into four stages based on the Tumor Node Metastasis Staging System. This has assisted doctors and their patents to understand the severity of their cancer but putting cancer into distinct stages has certain limitations and some drawbacks.
Starting January of 2018, some oncologists have started using a different system to organize breast cancer and treatment. It is more accurate and will lead to less extraneous treatment.
The new guidelines involve adding a genetic factor to the staging process. Not the person’s DNA, but the DNA in the tumor itself.
How cancer is currently ranked
The current method of ranking breast cancer uses four stages along with a stage 0. The TNM staging system is often used to determine which stage a cancer is in.
Stage 0 is used for non-invasive cancers such as DCIS (ductal carcinoma in situ). There are tumor cells but they are not invading neighboring cells and are sometimes called pre-cancers.
Stage I is for invasive cancers present in the breast but they are still tiny and have not yet spread very far.
Stage II is for invasive cancers that have spread to the lymph nodes but are still mostly localized inside the breast.
Stage III is for invasive cancers which have started to spread to the edges of the breast and threaten to move beyond.
Stage IV is for invasive cancers that have spread beyond the breast and have caused tumors in other parts of the body such as the bones, lungs, or skin.
The TNM staging system is often used to put the breast cancer into a stage. It looks at three factors: the size of the tumor, how much it has impacted the lymph nodes, and whether it has metastasized.
Estrogen and progesterone receptor status is also used as is the production of a protein called Her2 and the grade of the cancer, which is how much the tumor cells visually represent healthy cells.
But generally, the tumor size, lymph node involvement, and whether or not the cancer has metastasized are the three primary factors in the TNM staging system.
A fourth factor
Rishi Sawhney, medical director of the Bayhealth Cancer Institute in Dover, Delaware, spoke about the new ranking method.
This new guideline uses the DNA of the tumor itself to help judge the severity of the breast cancer. As treatment is often based on the stage of the cancer, a more accurate ranking method will help doctors prescribe more precise treatments.
“In the long run it’s going to permit for better treatment,” said Dr. Rishi Sawhney.
This fourth component, genetics, requires genomic testing. This type of testing examines the DNA of the tumor itself, which are different from that of the surrounding healthy cells.
“It comes from the realization that biology and genes of the tumor will tumor will trump everything else.” Sawhney.
Genetic testing has been used before to help aid in accurately prescribing treatment methods. The presence of certain genes, such as BRCA1 and BRCA2, predisposes someone to developing breast cancer.
But genomic testing is different from looking at the patient’s normal DNA. Read on to learn more about the specifics.