Indocyanine green fluorescence mapping for sentinel lymph node biopsy in early breast cancer

Abstract

Introduction: A recent feasibility study (ICG-10) has confirmed high sensitivity of ICG fluorescence mapping for sentinel SLN detection in early breast cancer with 95% of nodes both blue and fluorescent. This follow-on study has specifically evaluated a combination of ICG and blue dye for SLN localization.

Methods: Fifty consecutive patients (49 female; 1 male) with unilateral clinically node negative invasive (37) and non-invasive (13) breast cancer underwent SLN biopsy with blue dye and ICG. Median patient age was 48 years and median invasive tumour size 19 mm for primary surgical patients. All patients had a normal pre-operative axillary ultrasound. Nodal and procedural detection rates were calculated for ICG alone and in combination with blue dye.

Results: A total of 87 nodes were retrieved with an average nodal count of 1.8 per patient (range 1-4). Eighty four nodes were blue and fluorescent and 3 fluorescent only. Nodal detection rates for ICG alone and combined with blue dye were 100% (87/87) and 96% (84/87) respectively. Metastases were present in 18 nodes (all blue and fluorescent) with 10 patients node positive overall (20%). The procedural detection rate for blue dye and ICG was 96% (48/50) and 2 patients had fluorescent only nodes which were deemed sentinel (4%).

Conclusion: Fluorescent imaging with ICG is a sensitive, valuable and safe method for SLN biopsy. A combination of blue dye and ICG is useful dual approach when radioisotope is unavailable. ICG has the potential to be a sole tracer agent with improved patient convenience and costs.

Keywords: Breast cancer; Indocyanine green; Photodynamic eye; Sentinel lymph node biopsy.