Table of ContentsView AllTable of ContentsBreast Cancer MicrometastasesDiagnosisSymptomsTreatment
Table of ContentsView All
View All
Table of Contents
Breast Cancer Micrometastases
Diagnosis
Symptoms
Treatment
Micrometastasesare small collections of cancer cells that have been shed from a cancerous tumor and have spread to another part of the body through the blood or lymph nodes.Micrometastases can then form a second tumor that’s too small to be seen on imaging tests, such as a mammogram or MRI (magnetic resonance imaging), and can only be seen under a microscope.
Micrometastases are often without symptoms and hard to detect because of their small size. Adjuvant chemotherapy and adjuvant radiation therapy are the most common treatment options.
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What Are Micrometastases in Breast Cancer?
Micrometastases are defined as clusters of cancer cells that are between 0.2 millimeters and 2 millimeters (mm) in diameter.Any smaller clusters are called isolated tumor cells.
If you have had asentinel node biopsy, your breast surgeon or oncologist may have mentioned micrometastases.They are extremely important in almostanytype of cancer and are the reason behindadjuvanttherapy—treatment given after surgery to help prevent arecurrenceof cancer.
When cancer first spreads and forms micrometastases, the only way to detect them is to remove the tissue where they are located and look at slices under a microscope. This is known as a lymph node biopsy.
However, it’s impossible to remove and examine every lymph node and organ in the body to check for small cancer cells. Oncologists assume tiny, undetectable metastases may exist outside of the breast(s) and lymph nodes when:
What size micrometastases are in breast cancer?Micrometastases are cancer cells that measure between 0.2 millimeters (mm) and 2 millimeters in diameter.
What size micrometastases are in breast cancer?
Micrometastases are cancer cells that measure between 0.2 millimeters (mm) and 2 millimeters in diameter.
By doing a biopsy of the sentinel node or nodes—the first few nodes that cancer would travel to—many women are spared a full axillary lymph node dissection (removal of many or all of the lymph nodes in the armpit).Since removing all the nodes can result in complications such aslymphedema(lymphatic swelling), a sentinel node biopsy is considered a safer option.
Research is ongoing to determine the significance of micrometastases in the sentinel node. Currently, it’s known that macrometastases (metastases larger than 2 mm) worsen the prognosis of the disease, as do micrometastases in the sentinel node.
Meanwhile, people who have isolated tumor cells in the sentinel node do not have a prognosis any worse than a person with no evidence of metastases to the sentinel node.
Having this information can help healthcare providers understand which patients will need a fullaxillary lymph node dissection, and which should consider adjuvant treatment of their breast cancer.
Because micrometastases are so small, they typically don’t cause symptoms like swelling of the lymph nodes seen in other forms of cancer. The only way to identify them is through microscopic testing.
What is the survival rate when cancer spreads to lymph nodes?The survival rate is described in terms of the percentage of people who are alive five years after a cancer diagnosis. For breast cancer that has spread to lymph nodes, the five-year survival rate is 86%.
What is the survival rate when cancer spreads to lymph nodes?
The survival rate is described in terms of the percentage of people who are alive five years after a cancer diagnosis. For breast cancer that has spread to lymph nodes, the five-year survival rate is 86%.
Adjuvant chemotherapyoradjuvant radiation therapyis used after a primary tumor has been removed to “clean up” any micrometastases near the origin of the tumor (via radiation) or anywhere in the body where they may have traveled (via chemotherapy).
For hormone receptor-positive disease, hormone treatments such as tamoxifen or letrozole can be as important as chemotherapy for treating metastases.
Which treatment you’ll need depends on where the metastases are believed to be. Your healthcare provider may recommend both chemotherapy and radiation, as well.
Breast cancers that have begun to travel to the lymph nodes are more likely to spread to other regions of the body. Therefore, it’s important to be aggressive with treatment.
How do you treat micrometastases in lymph nodes?The type of treatment will depend on the characteristics of the cancer. Treatment options include radiation, chemotherapy, hormonal therapy, and anti-HER2 medicine.
How do you treat micrometastases in lymph nodes?
The type of treatment will depend on the characteristics of the cancer. Treatment options include radiation, chemotherapy, hormonal therapy, and anti-HER2 medicine.
Summary
Micrometastasesare microscopic cancer cells that have escaped from the original tumor. These cells can be too small to see on imaging tests.
There are some characteristics of breast cancer, such as size and the presence of cancer in lymph nodes, that make micrometastasis more likely. A procedure called a sentinel node biopsy can help healthcare providers know where to look for micrometastases. They can be treated with chemotherapy or radiation.
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