Contrast-Enhanced Ultrasound Biopsy of Sentinel Lymph Nodes in Patients with Breast Cancer: Implications for Axillary Metastases and Conservation.

BACKGROUND: In breast cancer patients, sentinel lymph nodes (SLN) can be identified in the breast clinic using contrast-enhanced ultrasound (CEUS). This study aimed to characterize and compare the extent of axillary metastases in patients with either a benign or malignant SLN core biopsy at the end of surgical treatment. METHODS: Between 2009 and 2014, prospective data were collected on consecutive patients who underwent targeted core biopsy of SLN identified using CEUS in the breast clinic. Patients with abnormal lymph nodes (LN) detected on grey-scale ultrasound were not included. Patients whose initial SLN core biopsy was benign were compared with those who had a malignant SLN core biopsy. RESULTS: 555 patients with invasive breast cancer had SLN successfully identified and core biopsied. 487 had a benign SLN core biopsy and 427 (88 %) did not have metastases found in surgically excised SLN. Only 2 % of patients with an initial benign SLN core biopsy were found to have 2 or more LN macrometastases. 68 patients had a malignant SLN core biopsy and 52 % had 2 or more LN macrometastases. The total volume of LN metastases was higher in the group of patients who had an initial malignant SLN core biopsy (P < 0.001). CONCLUSIONS: Patients with a normal grey-scale ultrasound and benign SLN core biopsy are unlikely to have extensive axillary disease and may be ideally suited for axillary conservation. The decision to omit axillary LN dissection for patients with a malignant SLN core biopsy must be carefully considered because many will have undetected high-volume metastases.

Breast microcalcification: diagnostic value of calcified and non-calcified cores on specimen radiographs.

To determine if the specimen without calcification, as depicted on specimen radiography, made any contribution to the final histopathological diagnosis in comparison to the specimen with calcification. The records of 1312 stereotactic vacuum-assisted biopsies for breast microcalcifications between February 2000 and December 2010 were reviewed retrospectively. Following specimen x-ray the biopsy tissues with and without microcalcifications were sent in two separate pots (pot 1 and pot 2 respectively). The number of cores in each pot and the number of calcium specks within the cores were recorded. In 1135 of the 1312 (86%) cases the histopathological findings were similar for pot 1 and pot 2. In 165 cases (13%) the diagnosis was made solely on pot 1 while cores in pot 2 did not reveal any additional pathology. In 12 biopsies (1%) the significant pathology was only present in the specimen without any calcification. For "microcalcification only" breast lesions the specimen containing calcium will yield a correct diagnosis in 99% of cases. Cores containing no calcification rarely contribute to the diagnosis on their own, but in 87% of cases an accurate diagnosis would still have been made even if the targeted calcification had been missed.

Dynamic visualization of lymphatic channels and sentinel lymph nodes using intradermal microbubbles and contrast-enhanced ultrasound in a swine model and patients with breast cancer.

OBJECTIVE: Sentinel lymph node (SLN) identification using intradermal micro-bubbles and contrast-enhanced ultrasound (CEUS) has been recently reported in swine models and patients with breast cancer. The objective of this study was to investigate the dynamics of intradermally administered microbubbles as they travel to draining SLNs in pigs. We also performed a detailed study of the passage of microbubbles through breast lymphatic channels in a small group of patients with breast cancer. METHODS: Nine anesthetized healthy pigs were used for the study, and 5 female patients with primary breast cancer were recruited. Pigs received intradermal injections of a microbubble contrast agent in several territories to access lymphatic drainage to regional lymph nodes. Patients had periareolar intradermal injection of the microbubble contrast agent. Ultrasound examination was performed in the real-time contrast pulse sequencing mode with a commercial scanner. RESULTS: Sentinel lymph nodes were identified rapidly (<1 minute) and consistently in pigs. Intradermal microbubble injection and CEUS were found to have perfect concordance with the Evans blue dye method in locating swine SLNs. In all 5 patients with breast cancer, the microbubble contrast agent entered breast lymphatic channels and traveled to draining ipsilateral axillary SLNs within 3 minutes. CONCLUSIONS: Intradermally injected microbubbles traverse readily though lymphatic channels in pigs and human breast tissue. The ability to rapidly identify SLNs in the diagnostic period would enable targeted biopsy and may facilitate preoperative axillary staging in patients with early breast cancer.

Axillary ultrasound assessment in primary breast cancer: an audit of 653 cases.

Axillary lymph node status is an important factor in determining the prognosis and treatment in patients with invasive breast cancer. The introduction of the sentinel lymph node biopsy technique in the axilla has significantly reduced the number of patients requiring an axillary clearance procedure. However, a proportion of patients will be found to have axillary metastases after a sentinel node biopsy and will then require a second axillary surgical procedure. A retrospective audit of 653 consecutive patients presenting with invasive breast cancer showed a preoperative diagnosis rate of axillary disease of 23% using axillary ultrasound and fine-needle aspiration (FNA) together. We performed 232 axillary FNAs to diagnose 150 positive axillae. This avoided the need for a second operation in 150 women. The negative predictive value for axillary metastases using this technique was 79%. Overall accuracy was 84%.