Preoperative Axillary Ultrasound-guided Wire Localization and lymphoscintigraphy for Sentinel Lymph Node Biopsy in Breast Cancer Patients

Abstract

Introduction: Breast cancer is the highest incidence and mortality of female malignant tumors with negative axillary lymph nodes has been diagnosed mainly at an early stage. Sentinel lymph node biopsy (SLNB) is a standard screening technique for patients with early-stage breast cancer and clinically negative lymph nodes. Lymphoscintigraphy mapping was regularly used as the standard method for SLNB. Recently, ultrasound-guided wire localization (USGWL) is a well-established technique with superior outcomes. Therefore, we attempted to determine whether preoperative UGWL and lymphoscintigraphy (blue dye and isotope injection) improve SLN detection and false-negative rate in breast cancer patients undergoing SLNB and also identify clinical factors that may affect the diagnostic accuracy of axillary ultrasound. Patients and methods: Between December 2018 and June 2019, 55 patients with clinical T1-3N0 breast cancer who were eligible for an SLNB at Imam Khomeini Hospital in Tehran included in our study. Tumor characteristics and demographic information were collected from medical records, and prepared questionnaires by our surgical team. The day before SLNB, all patients underwent ultrasound-guided wire localization of SLN. Lymphoscintigraphy performed with an unfiltered 99mTc-labelled sulfur colloid peritumoral injection followed by methylene blue dye injection. The results were analyzed based on the permanent pathology report. Results: Among the 55 patients, (71.8%) SLNs were detected by wire localization, while (57.8%) SLNs were found by methylene blue mapping and (59.6%) by gamma probe detection. In comparison with wire localization and isotope injection, the methylene blue dye technique had low sensitivity of 72.2%, while both wire localization and isotope injection reached 77.8%. The sensitivity, specificity, and accuracy of UGWL were 77.8%, 42.1%, and 65.4%, respectively. Otherwise, the accuracy of methylene blue dye and isotope injection was 47.3% and 50.1%, respectively. Furthermore, there was a significant relationship between BMI, tumor size, laterality, reactive ALN, and the accuracy of preoperative AUS. But there was no significant correlation between age, weight, height, tumor biopsy, tumor location, the time interval between methylene blue dye and isotope injection to surgery, and also the type of surgery to the accuracy of preoperative AUS. Conclusion: Preoperative UGWL can effectively identify SLNs compared to lymphoscintigraphy (blue dye and isotope injection) in early breast cancer patients undergoing SLNB.

Keywords

• Breast cancer
• Sentinel lymph node
• Sentinel lymph node biopsy
• Axillary ultrasound
• Lymphoscintigraphy
• Wire localization