The Method of Intraoperative Evaluation Does Not Affect the False Negative Rate of Sentinel Lymph Nodes in Breast Cancer Patients.
Hope T Richard, Dana L Johnson, Carleton T Garrett, Michael O Idowu, Celeste N Powers. Virginia Commonwealth University, Richmond
Background: Axillary lymph node metastasis is an important prognostic indicator in breast cancer patients, and correct intraoperative interpretation is an important step in patient management. The best method to evaluate intraoperative sentinel lymph nodes (SLN) has been debated. In this study, we compare the interpretation of intraoperative sentinel lymph nodes in non-neoadjuvant (NNA) and neoadjuvant (NA) treated patients by touch imprint cytology (TIC), frozen section (FS), and touch imprint cytology + frozen section (TIC + FS).
Design: Intraoperative evaluation of sentinel lymph nodes in consecutive breast cancer patients performed between 1999 and 2010 were reviewed. The patients were separated into non-neoadjuvant or neoadjuvant treated groups and then further subdivided by method of evaluation. True negative (TN), true positive (TP), false negative (FN) and false positive (FP) rates were calculated for each category based on permanent section, and statistical analysis was performed using the Chi square test.
Results: The intraoperative diagnoses of 2169 SLN from 982 consecutive breast cancer patients were reviewed. No significant difference was noted between TIC, FS and TIC + FS in either the NNA (p=0.8939) or NA (p=0.3806) patient populations. The percent of positive SLN within the NNA TIC (17.2%) and TIC+FS groups (20.0%) did not differ significantly, nor did the percent of FP (0.71% TIC vs. 0.51% TIC+FS) and FN (7.9% TIC vs. 8.5% TIC+FS). In the NA patients, the percent of FP (0.0% TIC vs. 2.2% TIC+FS) and FN (10.1% TIC vs. 13.0% TIC+FS) were not significantly different. Overall, positive SLN were slightly less likely to be undercalled (FN) if a frozen section was performed. but the results were not statistically significant (TIC+FS – 33% of 18 positive cases called negative vs TIC – 48% of 31 positive cases called negative; p = 0.30).
|Non-Neoadjuvant Treated(n=1969)||Neoadjuvant Treated(n=200)|
|TIC(n=1542)||FS(n=37)||TIC + FS(n=390)||TIC(n=148)||FS(n=7)||TIC + FS(n=45)|