A novel, adaptable, radiographically opaque, multi-plane continuous filament marker for optimizing tissue identification, radiation planning, and radiographic follow-up

Abstract

Background: In breast cancer treatment, marking the tumor bed is an important aspect of the surgical component of therapy. Clear delineation of the tumor bed allows radiation oncologists a defined target for planning and delivering postoperative radiation therapy (XRT). Tumor bed marking also allows radiographic follow-up of the tumor bed on subsequent breast imaging. The aim of this assessment is to evaluate the ease and feasibility of utilizing a tumor bed filament marker (VeraForm  , Videra Surgical inc., USA) as a marker in post-operative benign surgical sites and malignant breast surgical tumor beds in breast cancer surgery. Methods:The filament marker is a novel radiopaque surgical filament that in lieu of clips and other markers is implanted in the surgical tumor bed during breast surgery. Following development of the filament marker, the researchers used breast phantoms and radiographic images to develop a series of geometric patterns of placement options that optimize comprehensive multi-plane radiographic interpretation of the exact tumor bed or surgical margin. Three breast surgeons at 3 separate institutions then used this filament as a continuous multi-plane marker in 20 patients during breast conservation surgery. In these patients, the filament marker was thus used to mark the tumor bed (breast cancer surgery) or surgical site (benign breast disease) instead of the more traditional devices such as clips or other metallic open framework devices.We then assessed 2 important factors related to this device; (I) the ease, feasibility, and accuracy of in vivo placement with oncoplastic and non-oncoplastic breast conservation surgery techniques; (II) the radiographic footprint this device left on standard imaging protocols of post-operative mammogram (MMG), computed tomography (CT) scan, breast magnetic resonance imaging (MRI) examinations, and ultrasounds (USs) for both routine follow-up imaging and for standard radiation planning.Results: There were no adverse events reported with the use of this device. The cases were then reviewed by a multidisciplinary team that included the original surgeon, a breast radiologist, and radiation oncologist.Their unanimous evaluation was that the filament marker clearly delineated all sides and planes of the tumor bed (cancer surgery) or surgical site (benign disease). Regardless of surgical technique utilized, this information provided precise 3D guidance for radiation planning and delivery as well as radiographic followup. The surgeons involved reported that delineating the bed with the filament marker was a quick and easy procedure and did not interfere with performing the planned surgical technique. Radiologists, surgeons, 610 Mitchell et al. Continuous radiopaque filament marker

Comparison of Tumor Bed Delineation Using a Novel Radiopaque Filament Marker Versus Surgical Clips for Targeting Breast Cancer Radiotherapy

“…The filament was able to be placed easily at the time of lumpectomy taking an average of 4 minutes to place. 23 No adverse events related to FM placement were observed. The FM is not palpable for patients.…”

“…Initial experience with this marker was reported by Mitchell and colleagues. The filament was able to be placed easily at the time of lumpectomy taking an average of 4 minutes to place 23 . No adverse events related to FM placement were observed.…”

“…FM is able to be threaded into the contour of the tumor cavity intraoperatively in lieu of surgical clips. A previous in-vivo proof of principle study 23 demonstrated the feasibility and ease of using FM to outline TBs of any 3-dimensional shape with adaptability to surgical techniques including in the setting of lumpectomy and oncoplastic reconstruction. This has led to FM use for TB marking during breast surgery.…”

Advancing Treatment Accuracy of Accelerated Partial Breast Irradiation

“…Nevertheless, there may be alternative solutions. Recently, a new radiographic, 3D surgical filament marker was introduced to improve tumour bed marking for radiotherapy planning [299]. A similar study as that demonstrated in this thesis (one conducted by a multi-disciplinary team involving breast phantoms) can be conducted with different surgical markers to assess their reliability in improving tumour bed delineation accuracy.…”