Initial results of a novel technique of clipped node localization in breast cancer patients postneoadjuvant chemotherapy: Skin Mark clipped Axillary nodes Removal Technique (SMART trial)

Abstract

Purpose Removal of clipped nodes can improve sentinel node biopsy accuracy in breast cancer patients post neoadjuvant chemotherapy (NACT). However, the current methods of clipped node localization have limitations. We evaluated the feasibility of a novel clipped node localization and removal technique by preoperative skin marking of clipped nodes and removal by the Skin Mark clipped Axillary nodes Removal Technique (SMART), with the secondary aim of assessing the ultrasound visibility of the various clips in the axillary nodes after NACT. Methods Invasive breast cancer patients with histologically metastatic axillary nodes, going for NACT, and ≤3 sonographically abnormal axillary nodes were recruited. All abnormal nodes had clips inserted. Patients with M1 disease were excluded. Post‐NACT, patients underwent SMART and axillary lymph node dissection. Specimen radiography and pathological analyses were performed to confirm the clipped node presence. Success, complication rates of SMART, and ultrasound visibility of the various clips were assessed. Results Twenty‐five clipped nodes in 14 patients underwent SMART without complications. The UltraCor Twirl, hydroMARK, UltraClip Dual Trigger, and UltraClip were removed in 13/13 (100%), 7/9 (77.8%), 1/2 (50.0%), and 0/1 (0%), respectively (P = .0103) with UltraCor Twirl having the best ultrasound visibility and removal rate. Removal of three clipped nodes in the same patient (P = .0010) and deeply seated clipped nodes (P = .0167) were associated with SMART failure. Conclusion Skin Mark clipped Axillary nodes Removal Technique is feasible for removing clipped nodes post‐NACT, with 100% observed success rate, using the UltraCor Twirl marker in patients with <3 not deeply seated clipped nodes. Larger studies are needed for validation.

Would Removal of All Ultrasound Abnormal Metastatic Lymph Nodes Without Sentinel Lymph Node Biopsy Be Accurate in Patients with Breast Cancer with Neoadjuvant Chemotherapy?

“…Limitations include a small sample size and additional cost that may be incurred secondary to multiple nodal localization devices; however, this may be negated by the cost of sentinel lymph node biopsy, which was omitted. SMART is a novel inexpensive technique [9] that can be used for removal of multiple clipped nodes, but it has limitations. A cost analysis will require future studies.…”

“…However, because sentinel lymph node biopsy was omitted, this additional cost may be negated by the cost of the sentinel lymph node biopsy mapping agents [17]. Skin mark clipped axillary nodes removal technique (SMART) is a recently described technique [9] that could be used for the removal of multiple clipped nodes with minimal cost. However, it is not ideal for the removal of more than two deeply seated clipped nodes.…”

Comparison of the Ultrasound Visibility of Tissue Markers in Metastatic Lymph Nodes after Neoadjuvant Chemotherapy in Patients with Breast Cancer

“…Portnow et al [ 15 ] reported the US visibility of four types of tissue markers—including UltraCor Twirl and UltraClip—in animal tissue models stimulating axillary echotexture, and UltraCor Twirl demonstrated the highest score on the grading system used by radiologists. Lim et al [ 14 ] reported that UltraCor Twirl showed the best US visibility and highest excision rate after NAC among the four different types of tissue markers, including UltraCor Twirl and UltraClip, in 14 patients. Our study results support those of previous studies; however, we investigated a larger number of patients and analyzed the visibility in the absence of residual suspicious lymph nodes on US after NAC.…”

“…However, US-guided localization of axillary lymph nodes after a partial or complete radiologic response to neoadjuvant chemotherapy may often be challenging to radiologists [ 12 , 13 ]. A few studies have reported the US visibility of tissue markers for axillary lymph node localization in animal model phantoms or in a small number of patients with different types of tissue markers [ 14 , 15 ]. However, to the best of our knowledge, no study has evaluated the visibility of tissue markers in metastatic axillary lymph nodes after showing a pCR on US.…”

Determining the factors affecting the visibilities of various clips in axillary nodes on magnetic resonance imaging (MRI)

“…Removal of clipped metastatic nodes can improve the accuracy of axillary staging in breast cancer patients after neo-adjuvant chemotherapy (NAC). 1 Various clips have been used in this setting, but the appearance of the clips on magnetic resonance imaging (MRI) and factors affecting their visibility have not been widely examined. We aimed to compare the visibility of various clips in axillary nodes on MRI and to determine the technical factors which may affect their visualization.…”