Abstract P3-01-02: A comparison of significance with indocyanine green fluorescence imaging method and computed tomography-lymphography in sentinel lymph node identification for early breast cancer patients
Authors: Abe H , Yamasaki K , Teramoto A , Yoneda K , Ogawa M , Kawasaki M , Kameyama M 
Published: May 2016

Abstract
Background: Sentinel lymph nodes (SLN) biopsy has been established as a standard of care in the treatment of early breast cancer. This technique represents a minimally invasive, highly accurate method of axillary staging and is an alternative to conventional axillary lymph node dissection. The combination of the radioisotope and dye-staining methods is the most accurate way to identify sentinel lymph nodes. We had reported feasibility and safety of a new technique of SLN identification using fluorescence imaging of indocyanine green (ICG) injection without any need for training. Recently, SLN identification using computed tomography-lymphography (CTLG) has been reported in Japan. This study investigated the comparison of significance with fluorescence imaging method and CTLG.
Patients and method: Between January 2013 and May 2015, 213 breast cancer patients without clinical evidence of lymph node metastasis were treated. On the day before the operation, CTLG was performed using 64-row multidetector CT. We performed an intradermal injection in the periareolar area, using 4 ml of contrast agent with 1 ml of local anesthetic. The contrasted lymph flow and SLN were identified in reconstructed three-dimensional imaging. The SLN spot was indicated by CT laser light navigator system. During the operation, fluorescence images were obtained using the fluorescence imaging system, Photpdynamic Eye (pde-neo, Hamamatsu Photonics Co., Japan). After 5 mg / 0.3ml ICG was injected intradermally in to the periareolar skin, lymphatic drainage was observed with fluorescence images. SLN biopsy was performed referring to the point by axillary compression technique by plastic device.
Results: The median age of the 213 patients was 59 (range 28 – 87) years old. CTLG and fluorescence imaging was safely performed in all patients. CTLG could visualize lymphatic flow and accurately identify SLN in 189 (89 %) and 196 (92 %) cases, respectively, whereas fluorescence imaging identified successfully lymphatic flow and SLN in all patients. Fluorescence imaging with axillary compression technique was visually easy to identify the location of SLN on the axillary skin even in obese patients. Lymphatic flows of CTLG were completely consistent with those of fluorescence imaging. The number of SLN identified by CTLG was significantly lower than that by fluorescence imaging (1.1 vs. 1.6, p&lt;0.01). Twenty seven patients (13%) were found to have lymph node metastases pathologically, and 7 of them had micrometastases of lymph node. In case of partial enhancement of SLN with CTLG, the rate of positive metastasis was significant higher compared to the cases of whole enhancement (p&lt;0.01), however, even if enhancement is poor, about 70 % cases without metastasis are present.
Conclusion: Both of fluorescence imaging and CTLG revealed easy and effective to detect SLN. The fluorescence imaging with fluorescence mapping showed strong fluorescence from all parts of the surgical field, which hindered identification of SLNs, and fluorescence imaging was more high detection rate of SLN.
Citation Format: Abe H, Yamasaki K, Teramoto A, Yoneda K, Ogawa M, Kawasaki M, Kameyama M. A comparison of significance with indocyanine green fluorescence imaging method and computed tomography-lymphography in sentinel lymph node identification for early breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-01-02.