What is the operative procedure for mastectomy and axillary clearance, including relevant anatomy?

From the Guidelines

A mastectomy with axillary clearance involves surgical removal of the entire breast tissue and lymph nodes from the axilla to treat breast cancer, with the procedure beginning with an elliptical incision encompassing the nipple-areola complex, extending laterally toward the axilla, as described in the most recent guidelines 1. The procedure is performed to remove the breast tissue and lymph nodes, allowing for accurate staging and guiding adjuvant therapy decisions, while potentially reducing recurrence risk.

Operative Procedure

The steps involved in the procedure include:

• An elliptical incision is made, encompassing the nipple-areola complex, and extending laterally toward the axilla.
• Skin flaps are raised, and the breast tissue is dissected from the pectoralis major muscle, preserving the pectoral fascia unless tumor invasion necessitates its removal.
• An axillary clearance (levels I-III) is performed, carefully identifying and preserving key structures:
  • The long thoracic nerve (supplies serratus anterior)
  • The thoracodorsal nerve (supplies latissimus dorsi)
  • The intercostobrachial nerves (sensory to upper inner arm)
• The axillary vein forms the superior boundary of dissection.
• The specimen is removed en bloc, hemostasis is achieved, and closed suction drains are placed before wound closure.

Relevant Anatomy

The relevant anatomy includes:

• The pectoralis major muscle
• The long thoracic nerve
• The thoracodorsal nerve
• The intercostobrachial nerves
• The axillary vein
• The serratus anterior muscle
• The latissimus dorsi muscle

Postoperative Care

Postoperative care includes:

• Drain management until output decreases below 30ml/24hrs
• Early physiotherapy to prevent shoulder stiffness
• Monitoring for complications, such as seroma formation, lymphedema, nerve injury, and shoulder dysfunction, as noted in the guidelines 1. The goal of the procedure is to comprehensively remove the breast tissue and lymph nodes, while preserving key structures and minimizing risks, as outlined in the most recent guidelines 1.

From the Research

Operative Procedure for Mastectomy and Axillary Clearance

The operative procedure for mastectomy and axillary clearance involves the removal of the breast tissue and axillary lymph nodes. There are different types of mastectomies, including:

• Halsted radical mastectomy, which involves the removal of the whole breast along with the pectoralis major and minor muscles and a complete axillary dissection 2
• Modified radical mastectomy, which involves the removal of the whole breast and most or all of the axillary lymph nodes, but preserves the pectoralis major muscle 2
• Skin and nipple-areola complex sparing mastectomy (SNSM), which removes all breast tissue while preserving native breast integrity, nipple-areola complex (NAC), and submammary fold 3
• Nipple-sparing mastectomy (NSM), which removes the breast tissue leaving no or little retroareolar ductal tissue but preserves the entire skin of the breast and the NAC 4, 5

Relevant Anatomy

The relevant anatomy for mastectomy and axillary clearance includes:

• The breast tissue, which is located in the subcutaneous tissue of the chest wall
• The axillary lymph nodes, which are located in the axilla and are divided into three levels:
  • Level I: lymph nodes located lateral to the pectoralis minor muscle
  • Level II: lymph nodes located behind the pectoralis minor muscle
  • Level III: lymph nodes located medial to the pectoralis minor muscle, also known as apical axillary nodes 6
• The pectoralis major and minor muscles, which are located in the chest wall and play a role in the removal of axillary lymph nodes
• The subclavian vein, which is located in the subclavian region and is an important anatomical landmark for level III axillary lymph node dissection 6
• The thoracoacromial artery and the lateral cutaneous branches of the intercostal nerves, which are located in the axilla and must be protected during axillary lymph node dissection to reduce postoperative complications 6

Axillary Clearance

Axillary clearance involves the removal of axillary lymph nodes, which is necessary for accurate postoperative staging and essential guidance for postoperative adjuvant therapy. Level III axillary lymph node clearance is necessary in some cases, such as those involving apical axillary nodes, and can be achieved through a skeletonized complete level III axillary lymph node dissection 6. The procedure involves:

• Splitting the pectoralis major muscle to expose the subclavian region
• Dissecting the fat on the surface of the subclavian vein and lifting the fascia on the surface of the subclavian vein
• Removing the lymphoid adipose tissue along the fascial space completely and skeletonizing the subclavian vein
• Protecting the pectoralis branches of the thoracoacromial artery and the lateral cutaneous branches of the intercostal nerves to reduce postoperative complications 6