Using US Twinkling Artifact to Identify Breast Biopsy Markers: Brief Report

Abstract

Breast biopsy markers play an essential role in the surgical management of patients with clinically node-positive breast cancer. Marking a pathology-proven lymph node ensures accurate imaging assessment of response to neoadjuvant systemic therapy and decreased false-negative rates in sentinel lymph node biopsy. There is a clinically unmet need to make breast biopsy markers, particularly in the axilla, more sonographically visible or identifiable for preoperative localization purposes. Previously described color Doppler US twinkling artifact of some breast biopsy markers in in vitro gel phantoms and in ex vivo cadaveric breasts suggests that twinkling of such markers can be leveraged for improved in vivo detection. In this retrospective case series of eight female patients (mean age, 58.6 years ± 12.3 [SD]), conventional B-mode US imaging failed to identify the biopsy marker associated with a surgical target in the breast or in an axillary lymph node. However, in each patient, the marker was successfully identified with the help of color Doppler US twinkling. Keywords: Breast, Ultrasound, Color Doppler US, Lymphatic, Artifacts, Biopsy Marker Published under a CC BY 4.0 license.

Keywords: Artifacts; Biopsy Marker; Breast; Color Doppler US; Lymphatic; Ultrasound.

Figure 1:

US twinkling to guide detection of the Q marker in an axillary lymph node after neoadjuvant systemic therapy. In patient 4, a 66-year-old female patient with invasive ductal carcinoma and axillary lymph node metastasis, (A) the postclip mammogram shows the Q marker in the sampled lymph node (arrow). The patient responded favorably to neoadjuvant systemic therapy, and at preoperative US in anticipation of radioactive seed localization (RSL) of the marked node, the Q marker could not be identified. (B) Survey US imaging with the C1–6 transducer identified twinkling (arrow) and its associated comet tail (chevron). (C) The twinkling was quickly reproduced with the 9L transducer (arrow) and (D) immediate B-mode interrogation confirmed features consistent with the Q marker (arrow). (E) The Q marker features could be reproduced, albeit more subtly, using the ML6–15 transducer (arrow). Using this information, US-guided RSL was performed, with (F) the postlocalization mammogram from mediolateral oblique view confirming the seed (arrow) partially in the lymph node and just inferior to the Q marker. (G) Specimen radiograph confirms the seed location (arrow) adjacent to the Q marker near the lymph node (black *).

Figure 2:

Intraoperative twinkling detection of the Q marker. In patient 3, a 52-year-old female patient with invasive ductal carcinoma and axillary lymph node metastasis, (A) the postclip mammogram shows the Q marker in the sampled lymph node (arrow). During preoperative routine diagnostic US, the Q marker was not identified. Intraoperative US before surgical prepping was performed the next day. (B) With the C1–6 transducer, a twinkling signature was identified (arrow) and (C) confirmed with the 9L transducer (arrow). Immediate B-mode interrogation could not confirm features of the Q marker. (D) To ensure that the twinkling was definitely from the Q marker, a small amount (approximately 0.5 mL) of methylene blue 0.5% (ProvayBlue 5 mg/mL, CENEXI, American Regent) was delivered by percutaneous angiocatheter under US guidance (arrow) to stain the perinodal tissue of the Q-marked lymph node and simultaneously aspirated to not create extensive tissue staining. (E) Once the lymph node with perinodal staining was retrieved, a specimen radiograph and pathologic evaluation confirmed the presence of the Q marker (arrow) within the specimen.

Figure 3:

Twinkling detection of the Q marker in the breast. In patient 6, a 70-year-old female patient with invasive ductal carcinoma, (A) the postclip mammograms show the Q marker in the pathology-proven malignancy on the craniocaudal view (arrow) and (B) the mediolateral oblique view (arrow). Mammographic-guided radioactive seed localization (RSL) would have been challenging given the far posterior and inferior location of the malignancy. (C) Survey US imaging with the 9L transducer quickly identified twinkling (arrow), which (D) upon immediate interrogation with B-mode imaging, confirmed features consistent with the Q marker (arrow). US-guided RSL was performed, and (E) postlocalization mammograms confirmed accurate targeting on the craniocaudal view (arrow) and (F) the mediolateral oblique view (arrow). (G) Specimen radiograph confirms the seed (arrow) adjacent to the Q marker.

Figure 4:

Twinkling of the cork marker. In patient 8, a 73-year-old female patient with atypical ductal hyperplasia, (A) the postclip mammograms show the cork marker on the craniocaudal (arrow) and (B) the mediolateral oblique (arrow) views. US-guided radioactive seed localization (RSL) was attempted for patient comfort. The cork marker could not be identified using conventional B-mode imaging with the ML6–15 transducer. (C) The C1–6 transducer quickly demonstrated the twinkling signature (arrow) which (D) was reproduced, albeit with less twinkling, with the 9L transducer (arrow). (E) Immediate repeat B-mode interrogation with an ML6–15 at the twinkling site confirmed features suggestive of the cork marker (arrow). RSL was performed under US guidance and (F) postlocalization mammograms confirmed the seed on the craniocaudal view (arrow) and (G) the mediolateral oblique view (arrow) adjacent to the cork marker. (H) Specimen radiograph shows the seed (arrow) adjacent to the cork marker.