Axillary Dissection Health Article

Definition

Axillary dissection is a surgical procedure that incises (opens) the armpit (axilla or axillary) to identify, examine, or remove lymph nodes (small glands, part of the lymphatic system, which filters cellular fluids).

Purpose

Axillary dissection is utilized to stage breast cancer in order to determine the necessity of further treatment based on cancer cell spread. Additionally, axillary dissection includes removal and pathological examination of axillary lymph nodes for persons having operable breast cancer. The anatomy of the axilla is complex and composed of several critical nerves, arteries, and muscles. Because of this complex anatomy and connection with the breast, the axilla is a common route for possible metastatic (cancer cell spread to distant areas within the body) involvement from breast cancer. The absence or presence of cancer cells in axillary lymph nodes is the most power prognostic (outcome) indicator for breast cancer. Axillary dissection is an accurate procedure for axillary node assessment (removal and pathological examination). Clinical examination of the breast (more specifically palpation, or feeling the affected area for lumps) for the axillary region is inaccurate and unreliable. The only method to identify whether or not a lymph node has cancer cells, is to surgically remove the node and perform examination with a microscope to detect abnormal cancer cells.

Demographics

If axillary dissection is not performed, recurrence of cancer in the armpit is common even after breast surgery. Recent evidence suggests that persons who underwent lumpectomy alone without axillary dissection had a 10-year average recurrence rate of 28% in the axilla. Generally, recent evidence also suggests that the more nodes and tissues removed in the axilla, the lower the risk of recurrence of cancer. Research also indicates that 10-year axillary cancer recurrence rates are low (10% for node negative and 3% for node positive) for women who have mastectomy and axillary node removal. The recurrence rate for breast cancer is approximately 17% for women who did not have axillary node removal.

Description

Lymph nodes (or lymph glands) are filtering centers for the lymphatic system (a system of vessels that collects fluids from cells for filtration and reentry into the blood). Additionally, there is a complex arrangement of muscles, tissues, nerves and blood vessels. Axillary dissection is surgically explained in terms of three levels. Level I axillary dissection is also called lower axillary dissection because it is the removal of all tissue below the axillary vein and extending to the side where the axillary vein crosses the tendon of a muscle called the latissimus dorsi. Level II dissection is continuous—it includes the removal of level tissues and further extensive removal of cancerous tissues. Level II dissection removes diseased tissues deeper in the middle (medial) area of another muscle called the pectoralis minor. Level III dissection is the most aggressive breast cancer axillary surgery, and it entails the removal of all nodal tissue (tissues related to the lymphatic system) from the axilla.

Diagnosis/Preparation

Operable breast cancer is the primary indication for axillary dissection. Persons receiving this surgery have been diagnosed with breast cancer and are undergoing surgical removal of the breast. Diagnosis of breast cancer typically involves palpation of a lump (mass), and other tests such as mammography (special type of x ray used to visualize deep into breast tissues) and biopsy. The specific diagnosis to estimate the extent of axillary (cancerous) involvement can be made by performing a sentinel node biopsy. The sentinel node is the first lymph node that drains fluid from the primary tumor site. If there is no presence of cancerous cells in the sentinel node, the likelihood that higher echelon lymph nodes have cancer is very small. Conversely, if cancerous cells are detected in the sentinel node, then axillary dissection is recommended.

Preparation for axillary dissection is the same as that for modified radical mastectomy. This includes but is not limited to preoperative assessments (special tests and blood analysis), patient education, postoperative care, and follow-up consultations with surgeon and cancer specialist (medical hematologist/oncologist). Psychotherapy and/or community-centered support group meetings may also be beneficial to treatment.

Aftercare

One of the major problems that can result from axillary lymph node removal is lymphedema (fluid accumulation in the arm). Postoperative aftercare should include the use of compression garments, pneumatic compression pumps, and massage to combat fluid retention. Additionally, persons may have pain and should discuss this with the attending surgeon. Other surgical measures for aftercare should be followed similar to persons receiving a modified radical mastectomy. Skin care is important and caution should be exercised to avoid cuts, bites, and skin infections in the affected area. Further measures to control lymphedema can include arm exercises and maintenance of normal weight.