S. Z. Bhagwagar1, T. Hughes2, G. Babiera3, A. B. Chagpar1 1Yale University School Of Medicine,Surgery,New Haven, CT, USA 2McPherson Hospital,Surgery,McPherson, KS, USA 3University Of Texas MD Anderson Cancer Center,Surgical Oncology,Houston, TX, USA
Introduction: Sentinel lymph node biopsy (SLNB) has been accepted as a minimally invasive means of assessing axillary lymph nodes in breast cancer patients. While many surgeons had used intraoperative evaluation (IOE) either with frozen section (FS) or touch imprint cytology (TIC) to dictate whether to complete an axillary lymph node dissection (ALND) in the same operative setting, the widespread acceptance of the ACOSOG Z-0011 trial has lessened the need to do so in patients with 1-2 positive nodes undergoing a lumpectomy. We sought to determine, in a contemporary context, what surgeons’ practices were vis-à-vis the use of IOE, and factors affecting the same.
Methods: An online survey of surgeons was performed using the American College of Surgeons Communities’ Platform. Surgeons were asked about their clinical setting as well as their current use of IOE for SLNB. Nonparametric statistical analyses were performed using SPSS Version 21.0. In order to control for multiple comparisons, a Bonferroni correction was applied to the threshold for statistical significance, resulting in a significant p-value < 0.006 (0.05/9).
Results: 270 surgeons responded to the survey. To the question "In patients undergoing SLNB, do you get IOE?", 71 (27.1%) stated that they did IOE on all patients, 104 (39.7%) stated that they did so only on mastectomy patients, and 87 (33.2%) reported that they did not use IOE at all. Factors correlated with the use of IOE included geographic location (urban/suburban/rural), and proportion of practice that was breast-related (p<0.001 for both). In addition, surgeons who felt that isolated tumor cells did not constitute a positive lymph node and those who felt that the risk of lymphedema after ALND was > 10% were more likely to use IOE selectively in mastectomy patients (p=0.003 and p=0.005, respectively). Surgeon age, duration in practice, practice type (academic/hospital employed/private practice), and perception of the risk of lymphedema after SLNB did not influence surgeons’ use of IOE. Furthermore, whether surgeons used FS or TIC for IOE did not affect whether they utilized IOE always or selectively.
Conclusion: While nearly 70% of surgeons use IOE, the majority do so selectively in mastectomy patients only. Surgeons with solely breast-related practices in urban areas were more likely to use IOE only on mastectomy patients; those who felt that a positive SLN was defined as tumor deposits > 0.2 mm and who felt the risk of lymphedema was > 10% after ALND were also more likely to do so.
