Cysteine Rhenium Colloid: A Novel Radiocolloid for Identifying Sentinel Lymph Nodes in Breast Cancer Surgery

Abstract

BackgroundMedical isotopes are required for sentinel node lymphoscintigraphy in breast cancer, but are in critical shortage. Our center uses a modification of the standard SC, called CRC, that has been shown to require less medical isotope for the same procedure. Our objective was to determine if there was a significant difference between SC and CRC in successful lymph node identification in breast cancer patients. Patients and MethodsThis was a retrospective cohort study using prospectively-collected data on 1205 consecutive early, clinically node-negative breast cancer patients who underwent a SNB between 2002 and 2008 at 2 tertiary hospitals in Canada. ResultsThere was no difference in successful lymph node identification rate (P = .50) or in the mean number of positive nodes identified between the 2 colloids (P = .88). The CRC group had a significantly lower rate of delayed adverse events (4.91% vs. 0.59%, P < .0001) even after adjusting for whether axillary dissection occurred on the same day as the biopsy (adjusted odds ratio, 0.12; 95% confidence interval, 0.04-0.40; P = .001). ConclusionOur findings suggest that there is no significant difference between CRC and SC in detecting sentinel nodes; however, CRC uses less medical isotopes. In the current climate of critical shortages of medical radioisotopes, radiocolloids should be selected for use based on amount of radioisotope required.