Near-Infrared Fluorescence Axillary Reverse Mapping (ARM) Procedure in Invasive Breast Cancer: Relationship between Fluorescence Signal in ARM Lymph Nodes and Clinical Outcomes

The involvement of axillary reverse mapping nodes in patients with node-positive breast cancer

INTRODUCTION

Axillary reverse mapping (ARM) procedure is useful in reducing lymphedema. However, concerns regarding oncologic safety have limited the adoption of the ARM procedure. This study aimed to evaluate the involvement of ARM nodes in node-positive breast cancer patients.

MATERIALS AND METHODS

Two hundred twenty-three node-positive patients were enrolled in this study: 90 were clinically node-negative, but had one or more positive sentinel lymph nodes (SLNs) (SLN-positive group); 68 were clinicopathologically node-positive (CpN-positive group); and 65 had confirmed nodal involvement and received neoadjuvant chemotherapy (NAC) (NAC group). All patients underwent axillary lymph node dissection with fluorescent ARM.

RESULTS

ARM nodes were involved in 33 (36.7%) patients of the SLN-group. Residual ARM nodes after SLN biopsy were involved in 11 patients (12.2%), including 5 patients (19.2%) with crossover type nodes and 6 patients (9.4%) with non-crossover type nodes. However, the difference in involvement rates between the two types was not high enough to be significant. Of these 11 patients, moreover, four patients had three or more than 3 involved SLNs. On the other hand, the involvement rate of ARM nodes in the NAC group was significantly lower than that of the CpN-positive group (35.4% vs. 64.7%: p < 0.01). Despite lower involvement, the risk of metastases in the ARM nodes was still too high to spare ARM nodes in both the NAC group and CpN-positive group.

CONCLUSIONS

Suspicious or involved ARM nodes should be removed even when detected in ARM procedure, particularly in NAC-group and CpN-positive-group patients.

Feasibility of Breast Cancer Metastasis Assessment of Ex Vivo Sentinel Lymph Nodes through a p-H&E Optical Coherence Microscopic Imaging System

Frozen-sectioned hematoxylin-eosin (H&E) image evaluation is the current method for intraoperative breast cancer metastasis assessment through ex vivo sentinel lymph nodes (SLNs). After frozen sectioning, the sliced fatty region of the frozen-sectioned specimen is easily dropped because of different freezing points for fatty tissues and other tissues. Optical-sectioned H&E images provide a nondestructive method for obtaining the insight en face image near the attached surface of the dissected specimen, preventing the freezing problem of fatty tissue. Specimens from 29 patients at Wanfang Hospital were collected after excision and were analyzed at the pathology laboratory, and a fluorescence-in-built optical coherence microscopic imaging system (OCMIS) was then used to visualize the pseudo-H&E (p-H&E) images of the SLNs for intraoperative breast cancer metastasis assessment, and the specificity, sensitivity, and accuracy were 100%, 88.9%, and 98.8% (n = 83), respectively. Compared with gold-standard paraffin-sectioned H&E images, the specificity, sensitivity, and accuracy obtained with the frozen-sectioned H&E images (n = 85) of the specimens were the same as those obtained with the p-H&E images (n = 95). Thus, OCMIS is a useful noninvasive image-assisted tool for breast cancer metastasis assessment based on SLN images.

Axillary reverse mapping using near-infrared fluorescence imaging in invasive breast cancer (ARMONIC study)

BACKGROUND

Axillary lymph node dissection (ALND) in patients with breast cancer has potential side effects, including upper-limb lymphedema. Axillary reverse mapping (ARM) is a technique that enables discrimination of the lymphatic drainage of the upper limb in the axillary lymph node basin from that of the breast. We aimed to evaluate ARM node identification by near-infrared (NIR) fluorescence imaging during total mastectomy with ALND and then to analyze potential predictive factors of ARM node involvement.

METHODS

The study enrolled 119 patients diagnosed with invasive breast cancer with an indication for ALND. NIR imaging using indocyanine green dye was performed in 109 patients during standard ALND to identify ARM nodes and their corresponding lymphatic ducts.

RESULTS

94.5% of patients had ARM nodes identified (95%CI = [88.4-98.0]). The ARM nodes were localized in zone D in 63.4% of cases. Metastatic axillary lymph nodes were found in 55% in the whole cohort, and 19.4% also had metastasis in ARM nodes. Two patients had metastatic ARM nodes but not in the remaining axillary lymph nodes. No serious adverse events were observed. Only the amount of mitosis was significantly associated with ARM node metastasis.

CONCLUSIONS

ARM by NIR fluorescence imaging could be a reliable technique to identify ARM nodes in real-time when ALND is performed. The clinical data compared with ARM node histological diagnosis showed only the amount of mitosis in the diagnostic biopsy is a potential predictive factor of ARM node involvement.

CLINICAL TRIAL REGISTRATION

NCT02994225.