Targeted axillary dissection with preoperative tattooing of biopsied positive axillary lymph nodes in breast cancer

Abstract

Sentinel lymph node biopsy (SLNB) has emerged as an alternative to axillary lymph node dissection during breast cancer surgery during the last 2 decades. However, there are several controversies regarding the indication of the sentinel node biopsy after neoadjuvant chemotherapy which can convert positive lymph nodes to negative. The false-negative rate after neoadjuvant chemotherapy is unacceptably high. This high false-negative rate can be decreased by marking of the positive lymph nodes and removal during sentinel lymph node biopsy procedure in addition to the sentinel lymph nodes. The aim of this study was to investigate the possibility of carbon tattooing of the positive sentinel lymph nodes before neoadjuvant chemotherapy. In 2016, a prospective protocol was launched investigating the black carbon tattooing procedure of the suspective and positive axillary lymph nodes by injecting 0.1-0.5 carbon ink in normal saline under ultrasound guidance. All patients underwent black carbon tattooing of the suspected or positive axillary lymph nodes before the chemotherapy or one week before the primary surgery when chemotherapy was not indicated in the neoadjuvant setting. Sentinel lymph nodes together with lymph nodes marked by the black carbon ink were removed and histologically evaluated. So far 27 patients were treated under this protocol. Breast saving surgery was performed in 22 cases and mastectomy in 5 cases. All patients had invasive ductal carcinoma. In 20 patients neoadjuvant chemotherapy was indicated and in 7 patients primary surgery was performed. All lymph nodes marked by black carbon ink were successfully identified and removed. Sentinel lymph node biopsy was performed in 8 cases and sentinel lymph node biopsy followed by axillary dissection in 15 cases. Axillary dissection alone was performed in 4 cases. In 19 cases, the black carbon ink was present in the sentinel lymph node at the same time and in 4 cases carbon dye was present in other lymph nodes than the lymph node identified during SLNB, which corresponds to 17.4%. In the group of patients undergoing primary surgery, in one case from six, the sentinel lymph node was negative and the lymph node marked with carbon ink positive which represents false-negative lymph node and failure of the SLNB procedure. After neoadjuvant chemotherapy, there was no false-negative lymph node identified, but the conversion of the positive lymph nodes to negative was present in 10 cases (50%). There were no complications attributed to carbon ink tattooing. The results of positive sentinel lymph nodes tattooing have confirmed that this method is safe and allows a decrease in the false negativity rate during the sentinel node biopsy procedure.