Indocyanine green (ICG) fluorescence imaging versus radioactive colloid for sentinel lymph node identification in patients with breast cancer.

Abstract

674 Background: The usefulness of ICG fluorescence imaging produced by near-infrared ray for sentinel lymph node (SLN) identification in patients with breast cancer has been revealed. We herein compared and evaluated the outcomes between ICG fluorescence imaging with dye (ICG) and radioactive colloid with dye (RAC) in SLN identification in patients with operable breast cancer. Methods: Between March 2004 and December 2009, 309 patients with a tumor less than 3 cm in diameter and node-negative consisted of 149 patients in ICG and 160 in RAC were enrolled in this study. The mean age was 55 years in ICG and 54 in RAC. In the former, ICG was injected subdermally in the areola. Subcutaneous lymphatic channels draining from the areola to the axilla were visible by fluorescence imagings (Photodynamic eye: PDE, Hamamatsu Photonics Co.) immediately. After incising the axillary skin 1 cm cranial side from the disappeared point of fluorescence image, SLN was then dissected under the guidance of fluorescence with adequate adjustment of sensitivity. In the latter, radioactive colloid was injected subdermally in the areola the day before. After incising the axillary skin on the strong point of gamma probe (Navigator GPS power probe), SLN was then dissected under the guidance of gamma probe. Results: There were no significant differences between age, cancer stage and surgical procedures. The identification rate was 98.7% in ICG and 96.9% in RAC, respectively. The mean number of SLN was 3.7 (range: 1-11) in ICG and 2.0 (range 1-5) in RAC. The lymph node metastasis was revealed in 13.4% of ICG group and 13.8% of RAC group. The false negative rate was 0.67% in ICG and 0.62% in RAC. There were no intra- or postoperative complications associated with SLN identification. The cost was $46,007 (PDE: $46,000, ICG: $6.7) in ICG and $60,030 (GPS: $60,000, RAC: $30) in RAC. There were no significant differences in surgical outcomes between both methods. Conclusions: The evaluation of ICG fluorescence imaging is equal to that of radioactive colloid. In particular, ICG fluorescence imaging for SLN identification will be a greatly helpful tool for institutions without radioactive equipment. No significant financial relationships to disclose.