Value of Sentinel Lymph Node Biopsy in Breast Cancer Surgery with Simple Pathology Facilities -An Iranian Local Experience with a Review of Potential Causes of False Negative Results

Introduction: Sentinel lymph node biopsy (SLNB) is a precise procedure for lymphatic staging in earlybreast cancer. In a valid SLNB procedure, axillary lymph node dissection (ALND) can be omitted in nodenegativecases without compromising patient safety. In this study, detection rate, accuracy and false negativerate of SLNB for breast cancer was evaluated in a setting with simple modified conventional pathology facilitieswithout any serial sectioning or immunohistochemistry. Material and
Method: Patients with confirmed breastcancer were enrolled in the study. SLNB and ALND were performed in all cases. Lymph node metastasis wasevaluated in SLN and in nodes removed by ALND to determine the false negative rate. Pathologic assessmentwas carried out only by modified conventional technique with only 3 sections. Detection rate was determinedeither by lymphoscintigraphy or during surgery.
Results: 78 patients with 79 breast units were evaluated. SLNwas detected in 75 of 79 cases (95%) in lymphoscintigraphy and 76 of 79 cases (96%) during surgery. SLNmetastases was detected in 30 of 75 (40%) cases either in SLNB and ALND groups. Accuracy of SLNB methodfor detecting LN metastases was 92%. False negative rate was 3 of 30 of positive cases: 10%. In 7 of 10 cases withaxillary lymphadenopathy, LN metastastates was detected.
Conclusion: SLNB is recommended for patients withvarious tumor sizes without palpable lymph nodes. In modified conventional pathologic examination of SLNs,at least macrometastases and some micrometastases could be detected similar to ALND. Consequently, ALNDcould be omitted in node-negative cases with removal of all palpable LNs. We conclude that SLNB, as one of themost important developments in breast cancer surgery, could be expanded even in areas without sophisticatedpathology facilities.