الفهرس 
Anatomy of The BreastOnly 14 pages are availabe for public view
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Abstract
Optimal management of the axilla is essential for women with breast cancer undergoing operative treatment. Several surgical approaches are available for either staging or therapeutic procedures. The introduction of SLNB is resulting in marked changes in current clinical practice. The therapeutic impact and long-term outcomes will provide more important information influencing locoregional treatment decisions.
A tailored surgical approach with careful assessment of risks and benefits, together with patient preference, is guiding the evolving modern managementof the axilla (high accuracy and low morbidity) for women with early breast cancer.
Axillary nodal status is the most important prognostic factor for patients with breast cancer. Accurate assessment of ALNs provides either staging information or guidance regarding treatment options. It should be pointed out, however, that approximately 20% of women with no overt malignant cells in their axillary nodes eventually die from metastatic disease.
Predictors of ALN metastases, including clinical, radiological, pathological, and molecular characteristics of the primary tumors, are not always reliable.
Modern imaging modalities such as ultrasound, magnetic resonance mammography, positron emission tomography, and 99mTechnetium (Tc)-sestamibi scintimammography, are also insufficiently accurate in staging the axilla, particularly with small (<.5 cm) tumor deposits in ALNs.Surgical removal and histopathological examination of ALNs, thus the most reliable and accurate procedure for staging the axilla.
This article reviews the current management of the axilla in women with breast cancer, reviews the changes that have evolved in clinical practice, andprovides a comprehensive critique of a new selective targeted approach (sentinel lymph node biopsy [SLNB]) in patient management.
ALND (at least level II clearance) has been a routine part of breast cancer surgery since the era of Halsted. It provides not only prognostic informationto predict outcome but also excellent locoregional control of the disease. A mathematic model has suggested that a minimum of 10 nodes needs to beremoved to have a 93% predictive value that the remaining nodes are clear. The incidence of axillary recurrence with ALND is low, approximately 0%to 2%.It is, however, associated with clinically important morbidity, including impairment of shoulder movement, neuropathy, pain, and particularly lymphedema, the most important complication, which leadsto functional impairment, psychological morbidity, and decreased quality of life (QoL).The incidence of lymphedema after ALND ranges from 6% to 30%, with a greatly increased risk if radiotherapy has also been used.
ANS (four-node sampling) was introduced in the United Kingdom more than 30 years ago.This technique was based on the concept that the potentially involved ALNs should be palpated intraoperatively. At least four palpable lymph nodes need to be removed from the axillary tail and lower axillary fat to obtain 95% accuracy in staging the axilla.Two randomized controlled studies have been carried out ALND (level III) and ANS after mastectomy comparing or breast-conserving surgery in patients with early breast cancer.Patients with involved nodes on ANS had radiotherapy to the axilla. The results have shown that ANS was as effective as ALND in staging the axilla. Locoregional recurrence and long term survival were comparable between both groups. The combined data from these studies have confirmedcomparable overall survival, irrespective of nodal involvement, after a median follow-up of 10 years.
However, patients who were node negative on ALND had a significantly lower rate of axillary recurrence than those who were node negative on ANS (1.6% vs. 6.8%, P = .017). For patients with involved nodes, there was no statistically significant difference in axillary recurrence between ALND and ANS followed by radiotherapy. This suggested that the involved axilla can be treated effectively by radiotherapy. ANS was also associated with the least morbidity. Patients with ALND had greatly increased upper arm swelling, whereas those who had ANS followed by radiotherapy had decreased shoulder movement.
SLNB is a minimally invasive procedure that is an alternative to ALND or ANS in staging the axilla in patients with clinically node-negative breast cancers. It has the potential to improve the accuracy of axillary staging while reducing the number of unnecessary ALNDs and decreasing morbidity. The technique of SLNB is based on the premise that cancer cells that detach from the primary tumor are likely to arrive at, and be sequestered in, the first or sentinel node(s) to receive lymph from the tumor area. A tumor-free SLNtherefore indicates the absence of lymph node metastasis in the rest of the lymphatic basin; further ALND or radiotherapy is thus not required in suchcases.
An alternative to an ALND is primary regional radiotherapy. This is expected to give less morbidity: arm edema to a lesser extent (0–9%) and shoulder function impairment (0–1%) are noted. Dysesthesia and pain are neither mentioned nor expected. It is always a challenge to find alternative treatments leading to less complaints but this may not lead to major changes in tumor control and survival rates.