False Negative Rate of the Highest Radioactive Count of Sentinel Lymph Node in Early Stage Breast Cancer Patients
Prakasit Chirappapha MD*, Rujira Panawattanakul MD*, Watoo Vassanasiri MD*, Youwanush Kongdan MD*, Panuwat Lertsithichai MD, MSc*, Thongchai Sukarayothin MD*, Monchai Leesombatpaiboon MD*, Yodying Wasuthit MD*, Ronnarat Suvikapakornkul MD*
Affiliation : * Department of Surgery, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
Background : Axillary staging in women with breast cancer had changed drastically since the concept of sentinel lymph node
was introduced. Sentinel lymph node biopsy caused significantly less morbidity than axillary lymph node dissection. The
number of nodes removed are variable. However, removing more nodes results in a higher complication rate. If the lymph
node with the highest radiologic count could be used to represent the entire group of sentinel nodes then we might be able to
limit the number of nodes removed.
Objective : The present study was conducted to find the false negative rate of the sentinel lymph node with various radiologic
count in early breast cancer patients.
Material and Method: Women with early stage breast cancer and clinically node negative who had undergone sentinel lymph
node biopsy in the breast and endocrine surgery unit of Ramathibodi Hospital between July 1, 2014 and January 31, 2015
were recruited. Radiologic count of each sentinel nodes was documented and the false negative rate of the sentinel node with
the highest radiologic count was calculated. False negative rate is defined as the rate of nodal metastasis in lymph nodes other
than the node with the highest radiologic count.
Results : One hundred thirty sentinel lymph node biopsies were performed. Of this, 39 women had sentinel lymph node
metastasis. The false negative rate of the node with the highest radiologic count is 17.9%. The false negative rate was reduced
to 7.7% if we included the second and third highest nodes.
Conclusion : Removal of only the sentinel node with the highest radiologic count has an unacceptably high false negative rate.
This can be improved by removing the second and third highest nodes.
Keywords : Sentinel lymph node, Sentinel lymph node biopsy, Early breast cancer, Highest radiologic count
