Novel Dual Tracer Indocyanine Green and Radioisotope Versus Gold Standard Sentinel Lymph Node Biopsy in Breast Cancer: The GREENORBLUE Trial

A systematic review and meta-analysis of diagnostic performance of fluorescein-guided sentinel lymph node biopsy in early breast cancer

BACKGROUND

Evaluation of axillary lymph nodes status in cN0 axilla is performed by sentinel lymph node biopsy (SLNB) utilizing a combination of radioactive isotope and blue dye or alternative to isotope like Indocyanine green (ICG). Both are very resource-intensive; which has prompted development of low-cost technique of Fluorescein Sodium (FS)-guided SLNB. This systematic review and meta-analysis evaluate the diagnostic performance of FS-guided SLNB in early breast cancer.

OBJECTIVES

The objective was to evaluate the diagnostic performance of FS for sentinel lymph node biopsy.

METHODS

Eligibility criteria: Studies where SLNB was performed using FS.

INFORMATION SOURCES

PubMed, EMBASE, Cochrane library and online clinical trial registers. Risk of bias: Articles were assessed for risk of bias using the QUADAS-2 tool.

SYNTHESIS OF RESULTS

The main summary measures were pooled Sentinel Lymph Node Identification Rate (SLN-IR) and pooled False Negative Rate (FNR) using random-effects model.

RESULTS

A total of 45 articles were retrieved by the initial systematic search. 7 out of the 45 studies comprising a total of 332 patients were included in the meta-analysis. The pooled SLN-IR was 93.2% (95% confidence interval [CI], 0.87-0.97; 87% to 97%). Five validation studies were included for pooling the false negative rate and included a total of 211 patients. The pooled FNR was 5.6% (95% confidence interval [CI], 2.9-9.07).

CONCLUSION

Fluorescein-guided SLNB is a viable option for detection of lymph node metastases in clinically node negative patients with early breast cancer. It achieves a high pooled Sentinel Lymph Node Identification Rate (SLN-IR) of 93% with a false negative rate of 5.6% for the detection of axillary lymph node metastasis.

Cost-Effectiveness of Radar Localisation Versus Wire Localisation for Wide Local Excision of Non-palpable Breast Cancer

BACKGROUND

Wire localisation (WL) is the "gold standard" localisation technique for wide local excision (WLE) of non-palpable breast lesions but has disadvantages that have led to the development of wireless techniques. This study compared the cost-effectiveness of radar localisation (RL) to WL.

METHODS

This was a single-institution study of 110 prospective patients with early-stage breast cancer undergoing WLE using RL with the SCOUT® Surgical Guidance System (2021-2023) compared with a cohort of 110 patients using WL. Margin status, re-excision rates, and surgery delays associated with preoperative localisation were compared. Costs from a third-party payer perspective in Australian dollars (AUD$) calculated by using microcosting, break-even point, and cost-utility analyses.

RESULTS

A total of 110 WLEs using RL cost a total of AUD$402,281, in addition to the device cost of AUD$77,150. The average additional cost of a surgery delay was AUD$2318. Use of RL reduced the surgery delay rate by 10% (p = 0.029), preventing 11 delays with cost savings of AUD$25,496. No differences were identified in positive margin rates (RL: 11.8% vs. WL: 17.3%, p = 0.25) or re-excision rates (RL: 14.5% vs. WL: 21.8%, p = 0.221). In total, 290 RL cases are needed to break even. The cost of WLE using RL was greater than WL by AUD$567. There was a greater clinical benefit of 1.15 quality-adjusted life-years (QALYs) and an incremental cost-utility ratio of AUD$493 per QALY favouring RL.

CONCLUSIONS

Routine use of RL was a more cost-effective intervention than WL. Close to 300 RL cases are likely needed to be performed to recover costs of the medical device.

CLINICAL TRIAL REGISTRATION

ACTRN12624000068561.

Evolution of Indocyanine Green Fluorescence in Breast and Axilla Surgery: An Australasian Experience

The evolution of indocyanine green (ICG) fluorescence in breast and axilla surgery from an Australasian perspective is discussed in this narrative review with a focus on breast cancer and reconstruction surgery. The authors have nearly a decade of experience with ICG in a high-volume institution, which has resulted in publications and ongoing future research evaluating its use for predicting mastectomy skin flap perfusion for reconstruction, lymphatic mapping for sentinel lymph node (SLN) biopsy, and axillary reverse mapping (ARM) for prevention of lymphoedema. In the authors' experience, routine use of ICG angiography during breast reconstruction postmastectomy was demonstrated to be cost-effective for the reduction of ischemic complications in the Australian setting. A novel tracer combination, ICG-technetium-99m offered a safe and effective substitute to the "gold standard" dual tracer for SLN biopsy, although greater costs were associated with ICG. An ongoing trial will evaluate ARM node identification using ICG fluorescence during axillary lymph node dissection and potential predictive factors of ARM node involvement. These data add to the growing literature on ICG and allow future research to build on this to improve understanding of the potential benefits of fluorescence-guided surgery in breast cancer and reconstruction surgery.

An Updated Review on the Emerging Role of Indocyanine Green (ICG) as a Sentinel Lymph Node Tracer in Breast Cancer

Sentinel lymph node biopsy (SLNB) has become the standard of care for clinically node-negative breast cancer and has recently been shown by clinical trials to be also feasible for clinically node-positive patients treated with primary systemic therapy. The dual technique using both radioisotope (RI) and blue dye (BD) as tracers for the identification of sentinel lymph nodes is considered the gold standard. However, allergic reactions to blue dye as well as logistics issues related to the use of radioactive agents, have led to research on new sentinel lymph node (SLN) tracers and to the development and introduction of novel techniques in the clinical practice. Indocyanine green (ICG) is a water-soluble dye with fluorescent properties in the near-infrared (NIR) spectrum. ICG has been shown to be safe and effective as a tracer during SLNB for breast cancer and accumulating evidence suggests that ICG is superior to BD and at least comparable to RI alone and to RI combined with BD. Thus, ICG was recently proposed as a reliable SLN tracer in some breast cancer clinical practice guidelines. Nevertheless, there is lack of consensus regarding the optimal role of ICG for SLN mapping. Specifically, it is yet to be determined whether ICG should be used in addition to BD and/or RI, or if ICG could potentially replace these long-established traditional SLN tracers. This article is an updated overview of somerecent studies that compared ICG with BD and/or RI regarding their accuracy and effectiveness during SLNB for breast cancer.