Anesthesia and Surgical Techniques for Partial Mastectomy with Sentinel Lymph Node Biopsy

Patient Selection and Anesthesia Options

The American Society of Anesthesiologists recommends that anesthesia for partial mastectomy with sentinel lymph node biopsy be chosen based on patient and tumor characteristics, with general anesthesia often preferred for larger tumors or more complex procedures 1
For patients with small tumors and clinically negative axilla, local anesthesia may be a viable alternative to general anesthesia, improving quality of life and reducing complications 1

The dual technique using radiocolloid and blue dye provides the highest success rates and lowest false negative rates compared to single-agent techniques, with a recommended identification rate of ≥85% and false negative rate ≤5% 2, 3
The surgeon should have demonstrated experience with false negative rates <10% and successful mapping >90%, and formal training with a didactic and practical component, as well as mentorship, is recommended 2, 3
A minimum of 20 sentinel lymph node biopsy procedures in combination with axillary dissection or under mentorship is suggested for proficiency 3

The use of frozen section analysis during sentinel lymph node biopsy may be reconsidered, as permanent section alone may not diminish the standard of care, and may reduce costs, operating time, and anesthetic side effects 4, 5
For every 100 patients evaluated intraoperatively, 16-17 will have positive nodes and 8-9 will have false negative results, highlighting the importance of accurate intraoperative assessment 4, 5

The thoracic paravertebral block (T1-T6) provides unilateral anesthesia of the hemithorax and is useful for mastectomy and axillary surgery, and can be combined with light sedation 5
The serratus anterior plane block effectively anesthetizes the lateral thoracic wall and axilla, and can be performed under ultrasound guidance 2, 5

The long thoracic nerve (C5-C7) should be preserved during axillary dissection, as it innervates the serratus anterior muscle and runs over the lateral thoracic wall 2, 5
The thoracodorsal nerve should be identified and preserved during sentinel lymph node biopsy, as it innervates the latissimus dorsi muscle 2, 6

For patients with ductal carcinoma in situ (DCIS) treated with mastectomy, sentinel lymph node biopsy should be considered, as 10-20% of patients may have invasive cancer, and approximately one-third of patients have invasive disease 2
Factors associated with axillary metastasis in DCIS include age ≤50 years, suspicious axillary nodes on radiologic evaluation, and comedonecrosis, and selective omission of sentinel lymph node biopsy may be feasible in patients >50 years without suspicious nodes 2