New grading system for Breast Cancer?
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.
Genomic testing is much more specific than genetic testing
Unlike normal genetic testing, genomic testing looks at the genes expressed in the tumor itself. Since cancer involves damage at the genetic level, the tumor will have different genes from the rest of the body.
Genomic testing not only looks at the gene sequence in the tumor itself but also looks at how they are interacting with other genes in nearby healthy cells in order to get a larger picture of the danger expressed by the cancer.
The genomic score will be determined by using Oncotype DX. Oncotype DX tests for 21 genetic mutations in breast cancer. The same company also has tests designed to be used with colon cancer and prostate cancer.
This method helps ensure more accurate treatment
For breast cancer, the genomic score ranges from zero to one hundred. Generally, a score over thirty one calls for a more aggressive treatment than is currently being administered.
Other results of the genomic testing allow for individualization of the treatment based on which genetic mutations are discovered. You can even tell how beneficial chemotherapy or radiation therapy will be, based on which genes are found during the test.
This is important because the current staging strategy does not take into account how efficacious chemotherapy or radiation therapy will be to the precise cancer type, which can result in extraneous treatments being given to the patient.
Reducing treatments that do not work will reduce the amount of stress patients undergo and can help their pocket book stay heavier, too.
It can also estimate chances of cancer recurrence
The test also helps to estimate how likely the chances are that the breast cancer will return after treatment, allowing patients to either raise their guard or lower it, depending on the results. The result is less uncertainty in the future, allowing for the patients to suffer through less stress.
Oncotype DX only tests for mutations caused by the breast cancer. It does not look at hereditary genetics, such as the BRCA1 and BRCA2 genes. Those factors are still important and should be looked at as well.
This test has been used in over 170,000 patients so far, and counting
Before, the approach was to use many types of treatments, based on the stage of the cancer. This helped to ensure that you covered your bases in ways to fight against the cancer but involved treatment methods which did not help.
These extraneous treatments can have negative health effects for the patient and can increase the financial burden as well.
Adopting the new method of ranking breast cancer, by allowing for a more accurate approach to treatment, avoids these negative health effects as much as possible. Doctors will be able to assign treatment similar to how they use a surgeon’s scalpel as opposed to beating the tumor with a hammer.
The new guidelines have only been in effect for a few months but their effects have already been felt by many patients.
So far, over 170,000 patients have had their breast cancer treatment adjusted based on the results of the Oncotype DX test.
This new test score provides accuracy all around
Sometimes the Oncotype DX score is more favorable than the old TNM method. This has resulted in women being moved down a stage, letting them receive less harsh treatment. The treatment will also be more effective as well, a double whammy for the fight against cancer.
Even the women who have not seen their cancer move a stage can appreciate the more targeted treatment that the testing allows.
An Oncotype DX score that lifts a cancer into a higher stage is also a good thing, because this means that the doctors will be able to catch aggressive cancers in their patients before they sneakily hit Stage IV, at which point the outcome becomes bleak.
However, the new guidelines have not yet been universally adopted. And even doctors who have adopted the new guidelines have not, generally, re-diagnosed their patients.
Dr. Rishi Sawhney hopes that the new guidelines will become widely adopted, not just in the United States but across the world as well. He believes that this will only help patients. “We’ll be more cutting edge,” he said.
Final thoughts
In January of 2018, oncologists started using a new set of guidelines to rank breast cancer into the various stages. This involves the use of a genomic test which looks at the DNA in the tumor itself.
The results of this test allow doctors to more accurately know what type of breast cancer they are dealing with and also allows them to use more effective treatment options while avoiding ineffective and potentially harmful treatments.
References
http://www.oncotypeiq.com/en-US
