Award winner of the resident essay contest, Ohio Chapter, American College of Surgeons Utility of lymphoscintigraphy for lymphatic mapping in breast cancer: A prospective study

Abstract

Abstract Purpose: Sentinel lymph node (SLN) identification using lymphatic mapping is gaining popularity in the management of invasive breast cancer. The purpose of this prospective study was to determine the utility of preoperative lymphoscintigraphy (LS) in patients undergoing intraoperative lymphatic mapping (ILM). Methods: On the day of surgery, patients were injected with 400 μCi Tc-99m sulfur colloid (filtered) around the tumor or the biopsy cavity (100 μCi in each quadrant). The patients undergoing needle localization biopsy received a single injection of 400 μCi. Imaging was performed for 30 minutes and after 2 hours following the injection to trace the movement of radionuclide. A biplanar imaging technique was utilized for the localization of the sentinel node. The patients were then taken to the operating room, where ILM was performed utilizing a hand-held gamma detector probe (GDP) and isosulfan blue dye (IBD). Any sentinel nodes were identified and removed; subsequently, a standard axillary node dissection was performed. Results: One male and 24 female patients (n = 25) enrolled in and completed the study. Primary breast tumor sites were in the following quadrants: upper outer (15), lower outer (2), upper inner (3), lower inner (2), and central (3). A SLN was identified by ILM in 23 25 (92%) patients. None of the patients with a histologically negative SLN had axillary metastasis. Preoperative LS identified a suspected sentinel node (SN) in 17 25 (68%) patients. In all 17 of these patients, at least 1 SN was also identified by ILM. Intraoperative findings correlated with the LS (all axillary nodes) in all but one of these patients; ILM located an axillary SN in this patient in whom LS revealed a supraclavicular node. An axillary SLN was identified by ILM in 6 8 patients with negative LS. Furthermore, LS did not identify any drainage to internal mammary nodes, even in 8 patients with medial and central lesions. Conclusions: Although LS has value in identifying the draining lymphatic basin, negative LS does not preclude the identification of a SLN by ILM. LS does not appear to provide additional information to the surgeon performing ILM and, therefore, its routine use in breast cancer patients is not justified. However, its role in identifying internal mammary nodes needs further evaluation.