Retrospective observational study about reducing the false negative rate of the sentinel lymph node biopsy

Abstract

Reducing the false negative rate of sentinel lymph node biopsy (SLNB) for breast cancer patients has always been a focus of clinical research. We aimed to map the sentinel lymph nodes (SLNs) in detail, and analyze the factors related to SLNs located at locations that are often ignored by surgeons, to reduce the rate of false negatives from SLNB. A retrospective analysis involving 545 breast cancer patients who underwent SLNB in west China hospital between August 2010 and February 2016 was performed. Blue dye, radioisotope, or combined methods were used for tracing SLNs. Using blue dye, radioisotope, and a combination of blue dye and radioisotope successfully traced SLNs in 479, 507, and 525 patients, the detection rate was 88.2%, 93.9%, and 97.4%, respectively. Among the 1559 detected SLNs, 139 (9.6%) were located at the latissimus dorsi lateral margin, and 108 (6.9%) were located at level 2. Subcutaneous injection of radioisotope (P = .004) and intradermal injection of blue dye (P = .002) were independent factors associated with SLNs distributed at level 2 and the latissimus dorsi lateral margin, respectively. It was noteworthy that 2 of 7 patients had skipping metastasis in level 2, so subcutaneous injection of the isotope is strongly recommended for tracing SLNs distributed in level 2 because of the possibility of skipping metastasis. Though intradermal injection of blue dye was superior methods for tracing SLNs located at the latissimus dorsi lateral margin, we surprisingly found those patients with metastasis to the latissimus dorsi lateral margin nodes also could have metastasis to level 1 (expect for the latissimus dorsi lateral margin) nodes, it seemed that maybe there is no need to excise SLNs at the latissimus dorsi lateral margin in SLNB, whether such nodes should be regarded as useful for SLNB still needs to be determined by further large, multicenter clinical studies.

New classifications of axillary lymph nodes and their anatomical-clinical correlations in breast surgery

“…Of the other studies that cited this classification, none took advantage of the same demarcation and was able to support its truthfulness. Some authors, although interested in Clough et al’s indications, said that surgical treatment of the axillary region should be personalized based on the involvement of the lymph node status and did not report any data regarding the lymph node area involved [ 14 , 15 ].…”

“…Accuracy in identifying and removing SLN may limit this event. Specifically, it is important to correctly map SLNs, identifying areas often overlooked during surgery as well as factors related to inappropriate skin incisions, in order to eliminate those conditions that may make difficult the SLN dissection and may increase rate of false negative SLN [ 14 ]. In addition, this may provide useful guidance for training of unexperienced surgeons and to reduce the risk of postoperative lymphedema.…”