Percutaneous contrast-enhanced ultrasound for localization and diagnosis of sentinel lymph node in early breast cancer

Abstract

This study assessed the efficacy of percutaneous contrast-enhanced ultrasound (CEUS) in localization sentinel lymph node (SLNs) for biopsy and diagnosis of metastatic SLNs in patients with early breast cancer. From January to November 2017, seventy-five patients with early breast cancer confirmed by pathology were enrolled in this study. CEUS was performed after subdermal injection of ultrasound contrast agent (SonoVue, 2.0 ml in total dose) around the areola on the ipsilateral side of the breast. The contrast-enhanced lymphatic vessels and associated SLNs were observed and traced in real time. The lymphatic vessels and SLN were mapped and labeled on the skin surface. Sentinel lymph node biopsy (SLNB) was performed after injection of 2.0 ml methylene blue at same injection site of SonoVue. The accuracy of percutaneous CEUS localization of SLNs was determined compared to blue dye injection technique. The pathological results under blue dye guided biopsy were used as the reference standard to calculate the sensitivity and specificity of CEUS for the diagnosis of SLNs. A total of 163 SLNs obtained through SLNB following methylene blue tracing in 75 patients. There were 116 SLNs identified by percutaneous CEUS. The difference of detection rates between blue dye and CEUS was statistically significant (Z = −2.651, P = 0.008). The identification rate of SLNs by CEUS was 71.17% (116/163). The accuracy of percutaneous CEUS localization of axillary SLNs was 94.67% (71/75) compared to blue dye-guided biopsy. Among the 116 SLNs detected by percutaneous CEUS, pathologic results showed 51 positive SLNs and 65 negative SLNs whiles CEUS findings indicated 83 positive SLNs and 33 negative SLNs. Only 50 of 83 SLNs had metastasis on pathology, while 33 were detected as false positive. The sensitivity and specificity of CEUS for the diagnosis of metastatic SLN was 98.04%(50/51) and 49.23%(32/65), respectively. Percutaneous CEUS can be used as an effective method to localize the SLNs for guiding SLNB. This method has excellent sensitivity for identifying the SLNs but lower specificity for detecting metastatic SLNs in patients with early stage breast cancer.

Metastatic status of sentinel lymph nodes in breast cancer determined with photoacoustic microscopy via dual-targeting nanoparticles

“…At present, the clinical gold standard used to detect SLNs is labelling with blue dye or a radioactive nanocolloid and then performing SLNB. Although various nanoprobes based on different imaging modalities have been developed to map the metastatic status of SLNs [12][13][14][15][34][35][36] , few can distinguish T-MLNs from Inf-LNs. Tumour cell infiltration and proliferation of immune cells due to the induction of inflammatory factors result in the enlargement of SLNs 37 , usually leading to misidentification and unnecessary removal of benign SLNs during surgical resection 38 inflammation should be determined before SLN resection to reduce potential complications caused by unnecessary resection.…”

“…Several non-radiative approaches that can rapidly predict the metastatic status of SLNs have been developed. They include fluorescence imaging using a targeted fluorescent agent 11 , contrast-enhanced ultrasound using microbubbles 12 , nanoparticle-enhanced MRI 13,14 and imaging by surface-enhanced Raman scattering 15 . Because these agents are mainly taken up by macrophages in LNs, these methods distinguish between tumours metastatic SLNs (T-MLN) and inflamed LNs (Inf-LN) according to the lower signal intensity of metastatic SLNs.…”

Accuracy of CEUS-guided sentinel lymph node biopsy in early-stage breast cancer: a study review and meta-analysis

“…Of the 16 selected studies, 9 used SonoVue as CEUS material [26][27][28][39][40][41][42][43][44], 6 used Sonazoid [23][24][25][45][46][47], and 1 used DEFINITY [48]. The administration sites and methods of contrast agents mainly include intradermal [23-28, 39-44, 47] and subcutaneous [45,46] injection around areola or peritumoral parenchyma injection approaching the axilla [48].…”

“…The administration sites and methods of contrast agents mainly include intradermal [23-28, 39-44, 47] and subcutaneous [45,46] injection around areola or peritumoral parenchyma injection approaching the axilla [48]. SLN localization methods are diversified, including skin labeling [23,27,41,42,[44][45][46][47], guidewire localization [25,26,40,43,48], labeled peptide clip localization [28], iodine-125 seed implantation [39], and ultrasound-guided fluorescent dye injection [24]. Seven studies used the isotope-dye dual tracer method as a comparator [23,27,39,43,45,46,48], while another nine studies were compared with the simple dye method [24-26, 28, 40-42, 44, 47].…”

Contrast‐enhanced ultrasound for sentinel lymph node mapping in the routine staging of canine mast cell tumours: A feasibility study

“…24 The potential of this technique was validated in canine models, [25][26][27][28] prior to application in human patients diagnosed with breast cancer and cutaneous melanoma. [29][30][31][32][33][34] The main advantages are the wide availability of CEUS, low cost, safety and rapid clearance of the contrast, 35 no requirement for general anaesthetic, quick contrast diffusion to the LNs in real-time, 27 the ability to view the fine details of the lymphatics and LNs, 36 and minimal spillover of the contrast to secondary nodes. 28,37 The main disadvantages are the need to select which lymphatic basins to scan, and inter-operator variability.…”