Definition
Axillary dissection, also known as axillary lymph node dissection (ALND), is a surgical procedure in which lymphatic tissue, including lymph nodes, fat, and connective tissue, is removed from the axilla (armpit) region. The operation is primarily performed to assess, stage, or treat malignant disease, most commonly breast cancer, but may also be indicated for melanoma, sarcoma, or other cancers that spread to axillary lymph nodes.
Indications
- Breast cancer: Therapeutic removal of involved axillary lymph nodes after a positive sentinel lymph node biopsy or when clinically palpable nodes are present.
- Melanoma: Management of regional nodal metastasis when the primary lesion is located on the trunk, upper extremity, or shoulder.
- Other malignancies: Sarcoma, squamous cell carcinoma of the skin, or metastatic disease with axillary involvement.
Procedure Overview
- Pre‑operative planning: Imaging (e.g., ultrasound, MRI, PET/CT) is used to evaluate nodal status and to map the extent of dissection.
- Anesthesia: General anesthesia is standard; regional blocks may be employed for postoperative analgesia.
- Incision: A curvilinear incision is typically made along the lateral aspect of the breast or in the posterior axillary line.
- Dissection levels: Lymph nodes are classified into levels I, II, and III based on their relationship to the pectoralis minor muscle:
- Level I: Lateral to the pectoralis minor.
- Level II: Deep to the pectoralis minor.
- Level III: Medial to the pectoralis minor, extending to the subclavian vessels.
The extent of removal depends on clinical staging and intraoperative findings.
- Hemostasis and closure: Meticulous control of bleeding, placement of drains (often suction) to prevent seroma formation, and layered closure of the incision.
Complications
- Lymphedema: Chronic swelling of the ipsilateral arm due to disrupted lymphatic drainage; incidence varies (5–30 % depending on extent of dissection and adjuvant therapy).
- Seroma: Accumulation of serous fluid; most common early postoperative issue, often managed with aspiration.
- Neuropathy: Injury to the long thoracic, thoracodorsal, or intercostobrachial nerves may cause shoulder dysfunction or sensory loss.
- Infection: Surgical site infection rates are low but require prompt treatment.
- Restricted shoulder mobility: Resulting from pain, scar tissue, or nerve injury; physical therapy is recommended.
Alternatives and Recent Trends
- Sentinel lymph node biopsy (SLNB): Minimally invasive technique that identifies the first draining lymph node(s); used when clinically node‑negative to avoid full ALND.
- Targeted axillary dissection (TAD): Combines SLNB with removal of previously marked positive nodes, reducing the need for extensive dissection.
- Neoadjuvant therapy: Systemic treatment before surgery can downstage nodal disease, allowing some patients to forego ALND.
Historical Context
Axillary dissection was introduced in the late 19th and early 20th centuries as a means to control regional spread of breast cancer. Over the past three decades, randomized trials (e.g., ACOSOG Z0011, AMAROS) have demonstrated that, in selected patients with limited nodal disease, omission of complete ALND does not compromise overall survival, leading to a paradigm shift toward less extensive axillary surgery.
Current Guidelines
Professional societies such as the American Society of Clinical Oncology (ASCO), the National Comprehensive Cancer Network (NCCN), and the European Society for Medical Oncology (ESMO) provide algorithmic recommendations that incorporate tumor biology, nodal burden, and response to systemic therapy when deciding on the need for axillary dissection.
Post‑operative Care
- Monitoring of drains and wound healing.
- Early range‑of‑motion exercises and referral to physiotherapy.
- Education on lymphea prevention (e.g., compression garments, weight management).
- Surveillance imaging as indicated by oncologic protocol.