Node-positive breast cancer signifies that cancer cells, originating in the breast, have migrated to the nearby lymph nodes. The lymphatic system is a network of vessels and nodes that functions as part of the immune system. Lymph nodes act as filters, trapping foreign particles and, in this case, cancer cells. The presence of cancer within these nodes indicates the tumor has developed the ability to travel, which is a factor in planning treatment. This migration does not mean the cancer has spread to distant organs, but it does change how the cancer is classified and managed.
Diagnosis and Staging
Diagnosing node-positive breast cancer involves surgically assessing the lymph nodes in the underarm area, known as the axilla. The most common initial procedure is a sentinel lymph node biopsy (SLNB). During an SLNB, a surgeon identifies and removes the first one to three “sentinel” nodes that drain fluid from the breast. These nodes are then examined by a pathologist for cancer cells.
If cancer is found in the sentinel nodes, a more extensive procedure called an axillary lymph node dissection (ALND) may be performed. An ALND involves removing a larger number of lymph nodes from the armpit to determine the full extent of nodal involvement. The findings from these biopsies are a component of the cancer staging process, which uses the TNM (Tumor, Node, Metastasis) system. The ‘N’ in this system refers to the number and location of lymph nodes containing cancer, which heavily influences the overall stage.
Treatment Approaches
The treatment plan for node-positive breast cancer is more comprehensive because the cancer has demonstrated its capacity to spread. The goal is to address the primary tumor in the breast and any cancer cells that may have traveled to the lymph nodes or beyond. This involves a combination of local treatments, which target a specific area, and systemic treatments, which circulate throughout the body.
Local treatments include surgery and radiation therapy. Surgery can range from a lumpectomy, which removes the tumor and a small margin of surrounding tissue, to a mastectomy, which removes the entire breast. Following surgery, radiation therapy is often directed at the breast, chest wall, and the axillary lymph node region to eliminate any remaining cancer cells. For some patients, axillary radiotherapy may be used as an alternative to a full ALND after a positive sentinel node biopsy.
Systemic treatments are designed to reach cancer cells that might have escaped the breast and lymph nodes. Chemotherapy uses drugs to kill rapidly dividing cells. For cancers that are sensitive to hormones, known as estrogen receptor-positive (ER+) or progesterone receptor-positive (PR+), hormone therapy is used to block the hormones that fuel their growth. In cases where cancer cells overproduce a protein called HER2, targeted therapies can specifically attack these HER2-positive cells.
Understanding the Prognosis
While a node-positive diagnosis indicates a more advanced stage of breast cancer, the prognosis is highly individual. Modern treatments have significantly improved outcomes for patients with lymph node involvement. Several factors beyond the simple presence of cancer in the nodes are considered when determining a patient’s outlook.
The total number of affected lymph nodes is a prognostic factor; a patient with one to three positive nodes has a different prognosis than someone with ten or more. The tumor’s grade, which describes how abnormal the cancer cells appear, also plays a role, as lower-grade tumors tend to be slower-growing. The tumor’s hormone receptor status (ER/PR) and HER2 status are also important, as they determine if specific hormone or targeted therapies can be used. The five-year survival rate for breast cancer that has spread to regional lymph nodes is approximately 86.1%.
Life After Treatment and Lymphedema Risk
Life after treatment for node-positive breast cancer involves ongoing monitoring and management of potential long-term side effects. One of the primary considerations is the risk of developing lymphedema, a chronic condition characterized by swelling. This risk is a direct consequence of removing lymph nodes or damage to the lymphatic system from radiation, which can disrupt the normal flow of lymph fluid.
Lymphedema can cause swelling in the arm, hand, or chest on the side where the surgery was performed. While there is no cure for lymphedema, there are effective strategies to manage the condition. Preventative measures are encouraged, such as avoiding blood pressure cuffs, injections, and blood draws on the affected arm. Maintaining good skin care and managing weight are also recommended.
If lymphedema develops, treatments may include specialized physical therapy, compression garments, and specific exercises to promote lymph drainage. Regular follow-up appointments with the oncology team are necessary to monitor for any signs of cancer recurrence and manage any lingering effects of treatment.