The Guiding Significance of the Number of Positive Sentinel Lymph Nodes in Frozen Section for Intraoperative Axillary Dissection in Early Breast Cancer

Abstract

Purpose

The results of large randomised trials have changed the treatment strategy of axillary lymph nodes. Axillary lymph node dissection (ALND) can be avoided in some patients with one to two sentinel lymph nodes (SLNs) metastasis based on final paraffin section (FPS) results which called into question the need for intraoperative frozen section (FS). This study aims to assess the guiding value of the number of positive SLN detected via FS for intraoperative ALND.

Patients and Methods

This study retrospectively analyzed data from 3303 patients with breast cancer who underwent SLN biopsy between 2015 and 2019. Combined with the FPS results, FS sensitivity, specificity, and false negative rate (FNR) were calculated and the difference in the number of positive SLNs between FS and FPS was analyzed.

Results

The overall FNR of FS was 23.21%, which was 76.47% in isolated tumor cells, 62.28% in micrometastasis, and 12.09% in macrometastatic disease. The size of SLN metastasis were significantly associated with a higher FNR (p<0.001). The accuracy rate of the number of positive SLNs detected via FS was 92.62%. Human epidermal growth factor receptor 2 (HER2) (p<0.03) and Ki67 (p<0.02) were significant factors affecting the accuracy rate.

Conclusion

FS is a effective method for SLN biopsy, ALND can be avoided in patients with one or two positive SLNs detected via FS.

Keywords:

• breast neoplasms
• sentinel lymph node
• frozen section
• false negative rate
• axillary lymph node dissection

Acknowledgments

This research was funded by project of Natural And Science Foundation of Zhejiang Province, No. LY19H160005.

Ethical Approval/Informed Consent

This study was approved by the institutional Ethics Committee of Zhejiang Cancer Hospital (IRB-2018-137). The study was conducted in accordance with the ethical principles laid down in the Declaration of Helsinki. We declare that the data was anonymized and maintained with confidentiality. Written informed consent for the use of patient information in this study was obtained from all patients at the time of admission as a routine practice at zhejiang cancer hospital.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.