The breast area is surrounded by the lymphatic system, which carries a clear fluid collected from tissues, called lymph, draining it towards the heart. The lymphatic system mainly consists in the lymph nodes where the lymph is filtered and the lymphatic vessels that transport the lymph similar to the vessels in the circulatory system. This system is part of the immune system, transporting disease-fighting cells and fluids, and it is crucial for getting rid of body toxins, abnormal cells, waste and unwanted materials in the tissues and organs.
Breast cancer starts in the cells of the breast when there is an abnormal proliferation and growth of mutated cells. The tumour (uncontrolled cancer cells growth) starts in a localised place but later on these cells can invade surrounding tissues or even spread to other areas of the body by breaking away from the original tumour and entering lymph vessels, which branch into tissues throughout the body. When this process takes place, one may affirm that a metastasis has occurred. The presence/absence of cancer cells in the breast nearby lymph nodes helps doctors to: 1) understand how developed is the cancer, 2) to determine which is the disease prognosis, and 3) to set up the best treatment strategy for the patient recovery.
The current gold standard to determine if metastasis has occurred is the Sentinel Lymph Node Biopsy (SLNB), an invasive procedure that extracts via surgery the firsts lymph nodules draining from the breast to search for presence of cancer cells via immunopathological staining. If cancer cells are found there it may show that there has been a metastasis. Otherwise, if no cancer is found in those lymph nodes, the chance of finding cancer in any of the remaining lymph nodes is small. The HYPOSENS system achieves this evaluation without the need for surgery.