Product Code Database
A micrometastasis is a small collection of Cancer cell that has been shed from the original Neoplasm and spread to another part of the body through the Lymphatic system. Micrometastases are too few in size and quantity to be picked up in a screening or diagnostic test, and therefore cannot be seen with imaging tests such as a Mammography, MRI, ultrasound, PET, or CT scan scans. These migrant cancer cells may group together to form a second tumor, which is so small that it can only be seen under a microscope. Approximately 90 per cent of people who die from cancer die from Metastasis disease, since these cells are so challenging to detect. It is important for these cancer cells to be treated immediately after discovery, in order to prevent the relapse (regrowth of the cancer) and the likely death of the patient.
The detection of micrometastases in the sentinel lymph nodes (SLN) is the primary indicator of its spread to the regional lymph nodes, bone marrow, peripheral blood and ultimately to distant metastatic sites, since they are the first of the nodes that cancer would travel to. This concept applies to melanoma, breast cancer, and other solid tumors, including colorectal, esophageal, Stomach cancer, Lung cancer, head and neck, Vulvar cancer, and Penile cancer cancers. Therefore, the presence of these cells in the SLN can help make predictions regarding the patient’s diagnosis and prognosis. For example, it has been found that the prognosis of women who have micrometastases to the sentinel lymph node is poorer than that of women who do not have any evidence of tumor in these lymph nodes. The same applies to patients with melanoma and the other solid tumor cancers.
Before the micrometastases colonize at a distant site, the tumor cells can be found in the bone marrow or peripheral blood. Tumor cells found in the bone marrow are known as disseminated tumor cells (DTCs), and those found in the peripheral blood are known as circulating tumor cells (CTCs). These cells have successfully left the primary tumor microenvironment and the SNLs, and are able to survive in a non-native environment, which makes them more aggressive.
In order to eliminate micrometastases that are not near lymph nodes and have traveled to distant regions of the body, chemotherapy and radiation therapies are necessary. However, since most micrometastatic tumor cells are in the nonproliferative G0 phase, standard Cytotoxicity chemotherapies may not be as useful. Therefore, adjuvant chemotherapy and adjuvant radiation therapy are more effective to eliminate micrometastases, since they are aimed to target dividing and quiescent cells. Adjuvant therapies are administered after the removal of the lymph nodes. The significance of these therapies is to serve as a “clean up” method for those cells that have migrated elsewhere from the primary tumor. Researchers still question whether this treatment method to rid the body of this small cluster of cells that may or may not progress is worth the side effects that it may cause. Side effects include fatigue, hair loss, nausea, or vomiting. In addition, adjuvant therapies do not always result in a cure and they do not benefit all patients.
|
|
