Detectability of Hygroscopic Clips Used in Breast Cancer Surgery

Marking Techniques for Targeted Axillary Dissection Among Patients With Node-Positive Breast Cancer Treated With Neoadjuvant Chemotherapy

Invasive breast cancer with axillary lymph node (LN) invasion is a continuing problem worldwide. The morbidity associated with axillary LN dissection along with the high rate of nodal downstaging after neoadjuvant chemotherapy (NACT) made the standard treatment shift towards less invasive surgery. Sentinel lymph node biopsy (SLNB) after NACT is associated with high false-negative rates (13%-14%). To overcome this problem, it was concluded that the positive nodes should first be indicated with image-detectable markers and then removed together with SLNB: targeted axillary dissection (TAD). This review aims to describe and evaluate the different marking techniques for TAD in patients with node-positive breast cancer treated with NACT, namely: clip placement and guidewire localization; clip placement and 125I-labelled radioactive seed localization; clip placement and skin mark; clip placement and intraoperative ultrasound; tattooing with a sterile black carbon suspension; magnetic seeds; radar and infrared light technology localization. Targeted axillary dissection techniques have shown false-negative rates below 9% and identification rates above 95%. The most studied technique is guidewire localization, as it is also the oldest one. However, according to data gathered from this review, some newer techniques have shown to be very promising due to their statistical results and management factors.

Sonographic visibility of the UltraCorTM TwirlTM tissue marker

BACKGROUND

Tissue markers are inserted into the breast after percutaneous biopsy to mark the site of the lesion to facilitate potential re-localisation. Tissue markers are increasingly developed with improved sonographic visibility due to benefits conferred by ultrasound-guided localisation.

OBJECTIVES

We aim to study the sonographic visibility of the recently-introduced UltracorTM TwirlTM tissue marker and feasibility of its pre-operative localisation under ultrasound guidance.

METHODS

All patients who underwent insertion of the UltracorTM TwirlTM tissue marker in our institution from July 2017 to December 2018 were reviewed. Retrospective data including sonographic visibility, evidence of migration and rate of successful surgical excision were collected.

RESULTS

All tissue markers were visible on subsequent ultrasound with 198 (85.0%) well-visualised with high degree of confidence while 35 (15.0%) were moderately well-visualised with moderate level of confidence. None of the tissue markers were poorly visualised and none demonstrated migration. No statistical difference in sonographic visibility is seen based on interval duration between deployment and subsequent ultrasound assessment or depth of tissue marker.

CONCLUSION

UltracorTM TwirlTM demonstrates consistent sonographic visibility, identifiable with a high or moderate level of confidence with no associated migration. Its use in pre-operative localisation with ultrasound guidance is therefore both reliable and feasible.

Ultrasonic backscatter coefficient estimation in nonlinear regime using an in situ calibration target

Tissue characterization based on the backscatter coefficient (BSC) can be degraded by acoustic nonlinearity. Often, this degradation is due to the method used for obtaining a reference spectrum, i.e., using a planar reference in water compared to a reference phantom approach resulted in more degradation. We hypothesize that an in situ calibration approach can improve BSC estimates in the nonlinear regime compared to using the reference phantom approach. The in situ calibration target provides a reference within the medium being interrogated and, therefore, nonlinear effects would already be contained in the in situ reference signal. Simulations and experiments in phantoms and in vivo were performed. A 2 mm diameter titanium bead was embedded in the interrogated media. An L9-4/38 probe (BK Ultrasound, Peabody, MA) and an analysis bandwidth from 4.5 to 7.4 MHz were used in experiments. Radiofrequency data from the sample, bead, and reference phantoms were acquired at a quasi-linear baseline power level and at further increments of output power. Better agreement between the BSC obtained at low power compared to high power was observed for the in situ calibration compared to the reference phantom approach.

Surgery after Neoadjuvant Chemotherapy: A Clip-Based Technique to Improve Surgical Outcomes, a Single-Center Experience

BACKGROUND

This study aims to describe the surgical management of breast cancer patients after neoadjuvant chemotherapy, with attention to the impact on surgical outcomes of a clip-based marking technique.

METHODS

Patients who underwent NACT at the Breast Unit of the A. O Ordine Mauriziano of Turin from January 2018 and had a surgical intervention by January 2022 were included. Data on the feasibility of clip insertion, after-treatment visibility, and successful removal during surgery were collected prospectively. Surgical outcomes in terms of breast-conserving surgery and axillary dissection reduction were described.

RESULTS

In 51 patients who had surgery after NACT, 55 clips were placed (34 breast and 21 axillary clips). Ultrasound visibility of the clips was optimal (91%) as well as preoperative localization and retrieval within the surgical specimen. Moreover, the use of the clip positively affected surgical outcomes. In our study, clip insertion allowed to avoid mastectomy and axillary dissection in patients with a complete radiological response.

CONCLUSIONS

In our findings, the use of breast and/or lymph node clips has proved to be a simple and effective method to improve surgical conservative management of breast cancer patients after NACT.

Intraductal Migration of a Breast Tissue Marker Placed under Ultrasound Guidance during COVID-Induced Delay of Surgery

Breast tissue markers are common in current clinical practice and are susceptible to migration. Herein, we present the case of a 47-year-old woman with invasive breast carcinoma diagnosed through ultrasound-guided core biopsy, who underwent placement of a breast marker (HydroMARK^®) under ultrasound guidance 30 days after core biopsy and with subsequent marker migration to the nipple. The correct position of the marker was documented by mammography after its placement and by magnetic resonance imaging (MRI) after neoadjuvant chemotherapy. Migration of the marker to the nipple was evident only by mammography on the day of surgery. We hypothesized that an intraductal path was the route of marker migration in this patient. Marked ductal ectasia evident on MRI and histopathologic examination supported this hypothesis. To the best of our knowledge, this is the first published case of intraductal migration of a breast tissue marker.

Evaluation of sonographic detectability of different markers within an in vitro simulation model of the axilla

PURPOSE

Clip-marking of axillary lymph nodes with initial biopsy-confirmed metastasis is required for targeted axillary dissection (TAD), which includes sentinel lymph node dissection (SLND) and selective localization and removal of the clipped targeted lymph node. There have been several studies which examined the feasibility of TAD in routine clinical use. In this context, the optimal clip visualisation was noted as one of the crucial limiting factors. We, therefore, evaluated the sonographic detectability of 10 different commercially available markers within an in vitro model simulating the anatomical composition of the axilla.

METHODS

In this standardised model consisting of porcine fat with 30 mm thickness, the visibility of a total of ten markers was analysed in all 3 planes (parallel, diagonal, orthograde) with wire guidance and then classified into either "visibility good", "visibility moderate" or "visibility poor" with regard to the alignment of the transducer. Additionally, "real-life conditions" were simulated, in which the markers were searched without any wires guidance.

RESULTS

It was observed that, while not all markers are detectable in fatty tissue, markers with spherical shape (non-embedded Inconel or Nitinol) or rectangular-shaped Titanium markers with embedded material have a clear advantage. 3D-shaped markers can always be detected in all three axes, which is of particular importance in the axilla with its pyramid shape and fatty tissue.

CONCLUSION

The shape and the embedding of the material play a crucial role for visibility and efficacy of the marker, as reliable marking of suspicious and pathological axillary lymph nodes is essential for TAD.

New horizons in imaging and surgical assessment of breast cancer lymph node metastasis

Axillary nodal status is one of the most important prognostic factors in breast cancer. While sentinel lymph node biopsy (SLNB) is a safe and validated procedure for clinically node-negative patients, axillary management of clinically node-positive patients has been more controversial. Patients with clinically detected axillary metastases often benefit from neoadjuvant chemotherapy (NAC). Those who convert to node-negative disease following NAC are important to identify, since they can often be spared significant morbidity from axillary dissection. SLNB has shown widely varying false-negative rates (FNR) but with the use of dual mapping and surgical biopsy of 3 or more nodes, it is considered an acceptable method to stage the axilla in clinically node-positive patients who receive NAC. Various methods including targeted axillary dissection (TAD) have been shown to decrease the FNR of SLNB. We will review appropriate methods to identify a metastatic node and subsequent ultrasound-guided biopsy with tissue marking techniques. We underscore key points in monitoring axillary response, techniques to accurately localize the biopsied and clipped known metastatic node for surgical excision and the effect of various methods in reducing the FNR of SLNB, including the emerging concept of TAD on patient care.

Breast conservation and axillary management after primary systemic therapy in patients with early-stage breast cancer: the Lucerne toolbox

Primary systemic therapy is increasingly used in the treatment of patients with early-stage breast cancer, but few guidelines specifically address optimal locoregional therapies. Therefore, we established an international consortium to discuss clinical evidence and to provide expert advice on technical management of patients with early-stage breast cancer. The steering committee prepared six working packages to address all major clinical questions from diagnosis to surgery. During a consensus meeting that included members from European scientific oncology societies, clinical trial groups, and patient advocates, statements were discussed and voted on. A consensus was reached in 42% of statements, a majority in 38%, and no decision in 21%. Based on these findings, the panel developed clinical guidance recommendations and a toolbox to overcome many clinical and technical requirements associated with the diagnosis, response assessment, surgical planning, and surgery of patients with early-stage breast cancer. This guidance could convince clinicians and patients of the major clinical advancements purported by primary systemic therapy, the use of less extensive and more targeted surgery to improve the lives of patients with breast cancer.

Injectable Biodegradable Multimodal Mammography Marker

Introducing temporary markers for imaging studies is an idea, which in the proper clinical settings can be advantageous for patient compliance and in selected cases where a permanent marker is nondesirable. Hence, we developed injectable marker formulation using a biodegradable "pasty polymer" of poly(ricinoleic acid-co-sebacic acid) (PSA:RA) containing iodixanol and iron oxide as contrast agents that can serve as a visual marker for the region suspected to have tumor growth. The goal of this work is to noninvasively evaluate the visibility, shape, and degradation of the injectable PSA:RA formulation using magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound (US). Prescreening of the marker formulation was performed under MRI and CT scanning using agar gel phantom models with poly(l-lactide-co-ε-caprolactone) (PCL:LA) solid inserts (clips) that contained varying combinations of the contrast agents. The contrast agent combination with the PCL:LA clip that had the best visibility in both MRI and CT was selected and additionally tested as in PSA:RA formulation. Further, we evaluated the PSA:RA marker placement in bovine liver and poultry muscles. The PSA:RA formulation is predictable with good MRI, CT, and US visibility and shows no in vivo systemic toxicity symptoms when implanted subcutaneously in mice. Further, the advantage of PSA:RA formulation is its undefined shape and ease of injecting through a small gauge needle, making it possible to reach into the regions of the body.

A Review of Options for Localization of Axillary Lymph Nodes in the Treatment of Invasive Breast Cancer

Invasive breast cancer is a common disease, and the most common initial site of metastatic disease are the axillary lymph nodes. As the standard of care shifts towards less invasive surgery in the axilla for patients with invasive breast cancer, techniques have been developed for axillary node localization that allow targeted dissection of specific lymph nodes without requiring full axillary lymph node dissection. Many of these techniques have been adapted from technologies developed for localization of lesions within the breast and include marker clip placement with intraoperative ultrasound, carbon-suspension liquids, localization wires, radioactive seeds, magnetic seeds, radar reflectors, and radiofrequency identification devices.The purpose of this article is to summarize these methods and describe benefits and drawbacks of each method for performing localization of lymph nodes in the axilla.

Using a New Marker Clip System in Breast Cancer: Tumark Vision® Clip - Feasibility Testing in Everyday Clinical Practice

Background

This study presents first feasibility experiences with a new 3-dimensional (3D) marker clip system in clinical practice. The rate of clinical complete responses in the treatment of breast cancer patients is increasing; additionally, a change to targeted axillary dissection is being considered after neoadjuvant chemotherapy (NACT). Consequently, marker clips are needed which are reliable and easy to handle even in the axillary lymph node system.

Methods

A total of 50 patients from the Breast Care Unit of the Kliniken Essen Mitte were included. Clip marking of all 50 primary breast cancer lesions as well as 23 lymph nodes was performed using the Tumark Vision® clip. Following application, the position and visibility of the marker clip were monitored and documented in 2 axes.

Results

The feasibility of the Tumark Vision clip was excellent in everyday clinical practice as none of the markers dislocated. After clip marking of the tumor region and/or suspicious lymph nodes, all Tumark Vision clips could be detected in both axes. The 3D shape could be observed in all cases after application.

Conclusion

The new 3D-shaped marker clip seems to be a promising tool for marking breast cancer lesions and even lymph nodes before NACT. As there are many studies ongoing to prove the feasibility of a shift from standard axillary dissection after NACT towards targeted axillary dissection, the Tumark Vision clip seems to provide good visibility even in lymph nodes after NACT. Further studies are warranted.

Hygroscopic sonographically detectable clips form characteristic breast and lymph node pseudocysts

The use of hygroscopic sonographically detectable clips (HSDCs) has dramatically increased during the last years, especially in breast cancer patients who undergo neoadjuvant chemotherapy. The aims of this study are to define the appearance of HSDC sites in histopathological specimens, and to enable pathologists to recognize these sites and differentiate them from other lesions. We examined 124 breast cancer specimens in which the application of HSDCs was documented, 88 breast tissues and 36 lymph nodes, and analyzed the appearance of the clip site in these tissues. The clip site was clearly detected histologically in 79/88 (90%) of the breast specimens and in 29/36 (81%) of lymph node specimens. In most of the specimens, the HSDC site had a specific characteristic appearance of a pseudocyst, lined by layers of epithelioid histiocytes, sometimes with pseudopapillary formation, and with minimal or no fibrosis. This was the appearance in 69 of the breast specimens and in 23 of the lymph node specimens. In other specimens, scarring, scattered foamy macrophages and abundant siderophages were the predominant findings, as usually found in sites of other clips. As non-palpable breast lesions become more frequent, clips play a major role in the treatment of breast cancer, making them an important component of the communication among radiologists, surgeons, pathologists, and oncologists. HSDCs in tissues have a characteristic appearance with an epithelioid component. Pathologists should be able to recognize this finding, differentiate it from other breast lesions and include it in the pathology report.