Since 1867, when a theoretical basis for the surgical treatment of the axillary lymph nodes in breast cancer was stated by Moore in his article, axillary lymph node dissection has been carried out as an indispensable phase of the breast cancer treatment [1
]. For accurate staging and prevention of local recurrence, complete removal of at least level I and II lymph node groups is recommended [2
]. Nodal metastases from invasive breast cancer have clinical significance for three major reasons. First, the pathologic identification of nodal metastasis is an important prognostic indicator of systemic disease [4
]. The correlation is very strong, and the presence or absence of nodal metastases remains the single most important predictor of the eventual appearance of systemic metastases. Second, axillary node status has a particular value in the staging and choice of adjuvant therapy of the breast cancer patients [6
]. Unfortunately, physical examination, radiologic imaging of the axilla, or prognostic models based on primary tumor characteristics cannot accurately predict the occurrence of axillary metastases [6
]. Therefore, the National Institutes of Health Consensus Conference has recommended a level I and II axillary lymph node dissection for staging and regional control of breast cancer [11
]. It has been shown that for qualitative (metastases present or not) and quantitative evaluation of axillary status, sampling of at least 3-5 or 10 lymph nodes is required [12
]. And third, progressive growth of nodal metastasis, if left untreated, can cause local recurrences [14
]. On the other hand, axillary dissection has many short and long term morbidities. Loss of sensation, swelling, seroma, infection, nerve injuries, restriction of arm movements, and lymphedema are the most frequently encountered complications [16
]. In order to avoid these complications, some investigators have advocated a limited axillary sampling [22
]. Nevertheless, such an approach has the potential risk of missing some of the axillary metastases [23
The philosophy of axillary dissection for breast cancer has changed in the last few decades from therapeutic resection to selective diagnostic sampling. Only 50-60% of the primary breast cancer patients has nodal metastases . The sampling serves as a guide to adjunctive therapy and the reduced dissection should decrease the incidence of arm complications. The preponderance of breast lesions is now detected early, and such cases are candidates for breast conservation surgery which most women choose [24-26]. This usually entails lumpectomy with clear margins, axillary sampling and radiotherapy to decrease the risk of local recurrence and makes the results equivalent to modified radical mastectomy alone. Lymphatic mapping techniques using vital dyes or radionuclides with sentinel node biopsy is now thought to solve this problem and emerging as a technique to replace routine axillary node dissection. The concept of sentinel lymph node biopsy was first described by Cabanas in 1977 for the treatment of penile carcinomas . It has been suggested that the first lymph node draining the tumour area must be the first lymph node involved by the tumour. According to this hypothesis, if sentinel lymph node (SLN) is negative, then the whole lymphatic bed beyond this point will be negative. The initial experience in intra-operative lymphatic mapping has been gained from patients with melanoma. The first successful trial with this technique in breast cancer using vital dye was reported in 1994 by Giuliano et al . The authors identified sentinel nodes in 114 of 174 (65.5%) procedures and accurately predicted axillary nodal status in 109 of 114 (95.6%) cases. Since then, many studies, including pre-operative lymphoscintigraphy followed by intra-operative gamma-probe scanning technique, have been carried out to assess axillary status more accurately.
We report our initial results of an ongoing prospective study, using pre-operative lymphoscintigrapy and intra-operative gamma probe to investigate the efficacy of SLN biopsy for determining axillary status.