RESUMO
Background: Sentinel lymph node biopsy (SLNB) is the standard of care for women with node negative breast cancer. Tc99 nanocolloid is a popular tracer, facilitating preoperative lymphoscintigraphy to identify sentinel nodes. This study compares the number of sentinel lymph nodes identified at the time of surgery in women who had lymphoscintigraphy with those who did not.Method: All women with primary breast cancer undergoing a SLNB from 20032017 who were node negative and did not have neoadjuvant chemotherapy were retrospectively reviewed in this study.Results: 576 women who had Tc99 preoperative injection were included in the study. Three hundred patients (Group 1) underwent lymphoscintigraphy preoperatively and 276 (Group 2) had no lymphoscintigraphy. The mean age at diagnosis for Groups 1 and 2 were 56 and 58 years, respectively. Both groups were also found to be similar in terms of histological subtype, tumour location, size, and HER2- and Estrogen receptor (ER) status. The surgery for the breast primary was similar in groups 1 and 2. While both groups had a median number of 2 nodes identified, the mean number of nodes identified for Group 2 (2.12) was 10% higher than for Group 1 (1.92) (p = 0.0026).Conclusion: This is the largest series to show that a preoperative lymphoscintigram (scan) can safely be omitted when performing a SLNB. As newer tracers are being used (e.g. Iron Oxide), it is important to know that accuracy of SLNB is not compromised by omission of a scan