Evaluation of the Clinical Utility of the ICG Fluorescence Method Compared with the Radioisotope Method for Sentinel Lymph Node Biopsy in Breast Cancer

Tomoharu Sugie, Takayuki Kinoshita, Norikazu Masuda, Terumasa Sawada, Akira Yamauchi, Katsumasa Kuroi, Tetsuya Taguchi, Hiroko Bando, Hiroyasu Yamashiro, Tecchuu Lee, Nobuhiko Shinkura, Hironori Kato, Takafumi Ikeda, Kenichi Yoshimura, Hanae Ueyama, Masakazu Toi

This study compared the clinical utility of indocyanine green (ICG) fluorescence and radioisotope (RI) for sentinel lymph node (SLN) detection in breast cancer. Women with node-negative breast cancer underwent SLN biopsy using ICG fluorescence and RI. The primary end point was the sensitivity of ICG fluorescence compared with RI in the patients with tumor-positive SLNs. Secondary end points included detection rates for SLN, the additive effect of ICG fluorescence to RI, signature of positive SLNs according to tier, and adverse events related to ICG administration. A total of 847 women with clinical node-negative breast cancer underwent SLN biopsy, and 821 patients were included in the per-protocol analysis. SLN mapping was performed using ICG fluorescence and RI. The overall detection of SLNs using ICG fluorescence was identical to RI (97.2 vs. 97.0 %, P = 0.88), and the combination of both methods achieved a significant improvement compared with RI alone (99.8 vs. 97.0 %, P < 0.001). The detection rate for tumor-positive SLN was 93.3 % for ICG fluorescence and 90.0 % for RI, and the sensitivity of the ICG fluorescence method was 95.7 % (95 % CI 91.3-98.3, P = 0.11). The additional use of ICG significantly improved positive SLN detection for RI (97.2 vs. 90.0 %, P < 0.001). There were no serious adverse events related to hypersensitivity to ICG. The ICG fluorescence method may be an acceptable alternative to SLN detection using RI in breast cancer.