Use of axillary ultrasound to guide breast cancer management in the genomic assay era.

INTRODUCTION: Chemotherapy is conventionally offered to non-stage IV breast cancer patients with metastatic nodes. However, the RxPONDER trial showed that chemotherapy can be omitted in selected patients with 1-3 metastatic nodes if the 21-gene assay recurrence score is ≤25. We aimed to investigate if axillary ultrasound can identify this group of patients with limited nodal burden so that they can undergo upfront surgery followed by gene assay testing, to potentially avoid chemotherapy. METHODS: T1-3, node positive, hormone receptor-positive and HER2-negative breast cancer patients ≥50 years old with axillary lymph node dissection (ALND) were reviewed from 2 centres. Patients with neoadjuvant chemotherapy and bilateral cancers were excluded. Number of ultrasound-detected abnormal axillary nodes, demographic and histological parameters were correlated with the number of metastatic nodes found on ALND. RESULTS: 138 patients were included, 59 (42.8%) and 79 (57.2%) patients had 1-3 and >3 metastatic nodes on ALND respectively. On logistic regression and ROC analysis, the number of ultrasound-detected abnormal nodes was significant (p < 0.001) for predicting limited nodal burden (ROC AUC = 0.7135). Probabilities of <4 metastatic nodes with ultrasound cut-offs of 5, 6 and 8 abnormal nodes were 0.057, 0.026 and 0.005 respectively, with 100% specificity. CONCLUSION: A cut-off of ≤5 ultrasound-detected abnormal nodes can distinguish between patients with limited versus high nodal burden, with high specificity. Hence, incorporating the number of abnormal ultrasound-detected nodes into clinical practice may prove useful in guiding between upfront surgery and gene assay testing or neoadjuvant chemotherapy in this group of patients.

An unusual site for breast clip migration: A case report.

Clip migration following breast biopsy is a known complication. However, the migrated clip is usually found within the breast. We describe a rare case of delayed clip migration to the skin, following a magnetic resonance guided biopsy of the breast, highlighting its natural history of presentation and its treatment.

Injection mammoplasty: Normal imaging appearances, complications, and implications for mammographic screening.

BACKGROUND: The normal imaging appearances of the common agents used in injection mammoplasty and the challenges of mammography screening will be reviewed. METHODS: The local database from a tertiary hospital was accessed for imaging cases of injection mammoplasty. RESULTS: Free silicone is seen as multiple high-density opacities on mammograms. Silicone deposits can often be seen within axillary nodes due to lymphatic migration. Sonographically, a snowstorm appearance is seen when the silicone is diffusely distributed. On MRI, free silicone is hypointense on T1-weighted and hyperintense on T2-weighted images, with no contrast enhancement. Mammograms have a limited role in screening due to the high density of silicone. MRI is often required in these patients.Polyacrylamide gel and hyaluronic acid are seen as multiple collections on mammography. Polyacrylamide gel collections are of the same density as cysts, while hyaluronic acid collections are of higher density but less dense than silicone. On ultrasound, both can appear anechoic or show variable internal echoes. MRI demonstrates fluid signal with hypointense T1-weighted and hyperintense T2-weighted signal. Mammographic screening is possible if the injected material is located predominantly in the retro-glandular space without obscuring the breast parenchyma.On mammograms, autologous fat locules appear as lucent masses. Rim calcification can be seen if fat necrosis had developed. On ultrasound, focal fat collections can demonstrate varying levels of internal echogenicity, depending on the stage of fat necrosis. Mammographic screening is usually possible for patients after autologous fat injection as fat is hypodense compared to breast parenchyma. However, the dystrophic calcification associated with fat necrosis may mimic abnormal breast calcification. In such cases, MRI can be utilized as a problem-solving tool. CONCLUSION: It is important for the radiologist to recognize the type of injected material on the various imaging modalities and recommend the best modality for screening.

Determining the benefit of neoadjuvant chemotherapy in reduction of axillary dissection rates in Z0011 trial cohort with high nodal burden.

Background: In breast cancer patients fulfilling the Z0011 trial criteria, axillary lymph node dissection (ALND) is reserved for patients with a high nodal burden of ≥3 metastatic nodes. In this group of patients, to avoid an ALND, neoadjuvant chemotherapy (NACT) could be given instead to achieve nodal pathological complete response (pCR). However, the benefit of NACT in achieving nodal pCR and avoiding ALND in this group of patients is unknown. We aimed to determine the nodal pCR rate in this group of patients who otherwise would have needed an ALND. Methods: cT1-2N0 breast cancer patients, with histologically proven nodal metastasis, who underwent NACT were identified from a prospectively maintained database. The sonographic criteria of ≥3 abnormal nodes, which has been reported as highly predictive of high nodal burden, was then used to identify the high nodal burden group. Nodal pCR was determined based on the ALND following NACT. Results: Twenty-four patients with high nodal burden were identified. Mean age was 55.2 years. 91.7% had invasive ductal carcinoma and 29.2% had grade III cancer. 54.2% achieved nodal pCR which was associated with ypT (P=0.006). Nodal pCR was 75%, 70% and 30% in the triple negative, human epidermal growth factor receptor2 (HER2) positive and ER/PR+HER2- tumors, respectively. Conclusions: In the postulated T1-2 breast cancer patients with high nodal burden, needing an upfront ALND, NACT could result in nodal pCR of 54.2%, with higher pCR in certain subtypes. Hence, to minimize ALND risk, NACT should be offered in this high nodal burden group.

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.

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

LESSONS LEARNED: Removal of sonographically abnormal (up to 3) metastatic clipped nodes, without sentinel lymph node biopsy, could accurately predict axillary status in breast cancer patients receiving neoadjuvant chemotherapy. ypT and the first clipped node status were statistically significant factors for nodal pathologic complete response. This novel approach requires validation in larger studies. BACKGROUND: In patients who have node-positive breast cancer, neoadjuvant chemotherapy could result in nodal pathologic complete response (pCR) and avoid an axillary lymph node dissection (ALND). Axillary staging, in such cases, can be performed using targeted axillary dissection (TAD) with a low false negative rate. However, identification of sentinel lymph nodes (SLNs) after chemotherapy can be difficult, and currently, it is the standard to remove only one clipped node in TAD. We aimed to determine if removal of all sonographically abnormal metastatic clipped nodes, without SLN biopsy, could accurately predict the axillary status post neoadjuvant chemotherapy. METHODS: Patients with breast cancer with one to three sonographically abnormal metastatic axillary nodes were prospectively recruited. Each abnormal node had histology and clip insertion before neoadjuvant chemotherapy. After chemotherapy, the patients underwent removal of clipped nodes using the Skin Mark clipped Axillary nodes Removal Technique (SMART) and ALND. RESULTS: Fourteen patients were recruited, having a total of 21 sonographically abnormal metastatic nodes, with nine, three, and two patients having 1, 2, and 3 malignant nodes clipped, respectively. Mean age was 55.5 years; 92.9% and 57.1% of patients had invasive ductal carcinoma and grade III tumors, respectively; and 35.7% patients achieved nodal pCR. The first clipped node predicted the axillary status with a false negative rate of 7.1%. Adding to this another second clipped node, the false negative rate was 0%. Pathologic tumor staging after neoadjuvant chemotherapy (ypT) (p = .0390) and the first clipped node pathological response status (p = .0030) were statistically significant predictors for nodal pCR. CONCLUSION: Removal of sonographically abnormal metastatic clipped nodes using SMART, without sentinel lymph node biopsy, could accurately predict axillary status. This finding needs validation in larger studies.

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).

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.

Imaging features of micropapillary DCIS: correlation with clinical and histopathological findings.

RATIONALE AND OBJECTIVES: The aim of this study was to describe the mammographic, sonographic, and magnetic resonance imaging (MRI) findings of micropapillary ductal carcinoma in situ. MATERIALS AND METHODS: Between May 2004 and April 2008, the pathology database of a single institution was reviewed for patients diagnosed with histologically proven DCIS with a predominant micropapillary component. Clinical data and preoperative imaging studies, including mammography, sonography, and/or MRI, were reviewed. RESULTS: Forty-one patients (mean age, 55 years; range, 33-82 years) with 42 tumors were included in this study. Most tumors (n = 32 [76%]) were detected on screening mammography, with a mean tumor size of 4.7 cm (range, 0.5-13 cm). Of 42 tumors, seven (16%) were multicentric, and 23 (54%) were high nuclear grade. Calcifications were identified in 36 tumors (86%) on mammography, most frequently with pleomorphic morphology (15 tumors [42%]). Sonography was frequently normal (17 of 36 [47%]). When abnormal, irregular mass and angular margins were the most common sonographic features. All four tumors with MRI showed non-mass-like enhancement and showed the best correlation with pathologic size. CONCLUSIONS: Micropapillary ductal carcinoma in situ is a unique subset of in situ cancer that is frequently clinically occult but has a large mean size at diagnosis and demonstrates highly suspicious features at imaging including pleomorphic calcifications on mammography and an irregular mass at sonography. MRI may be the imaging modality of choice for delineation of disease extent and warrants further validation.