Percutaneous Ultrasound-Guided Core Needle Biopsy: Comparison of 16-Gauge versus 14-Gauge Needle and the Effect of Coaxial Guidance in 1065 Breast Biopsies - A Prospective Randomized Clinical Noninferiority Trial.

PURPOSE: Ultrasound-guided core needle biopsy (CNB) is considered the standard assessment to diagnose sonographically visible suspicious breast mass lesions. Based on nonrandomized trials, the current German guidelines recommend at least three cylinders with ≤ 14-gauge needle biopsy. However, no recommendation is made as to how many specimens are needed with a smaller needle size, such as 16-gauge, or if biopsy with coaxial guidance improves diagnostic accuracy and quality. Therefore, in a prospective monocentric unblinded randomized controlled clinical noninferiority trial, the diagnostic accuracy of 16-gauge versus 14-gauge core needle biopsy, with and without coaxial guidance, was evaluated. MATERIALS AND METHODS: 1065 breast biopsies were included in order to analyze the number of core samples necessary to obtain an appropriate rate of diagnostic quality adequate for histological evaluation, and to achieve high diagnostic accuracy and diagnostic yield. Histological results were verified by surgery or long-term follow-up of at least two years up to five years. RESULTS: In order to obtain an additive diagnostic accuracy of > 99 %, a minimum of two cylinders with 14-gauge biopsy were required. The diagnostic accuracy and the diagnostic quality of 14-gauge biopsy were not affected by the coaxial technique. When performing a 16-gauge biopsy, five cylinders were required to achieve an additive diagnostic accuracy of > 99 %. Without coaxial guidance, 16-gauge CNB required at least three samples, whereas five needle passes with coaxial-guided 16-gauge biopsy were needed. CONCLUSION: The diagnostic accuracy and quality of ultrasound-guided 16-gauge core needle biopsy were inferior to the 14-gauge needle size, regardless of the use of a coaxial technique.

Dynamic adhesion of eryptotic erythrocytes to immobilized platelets via platelet phosphatidylserine receptors.

Glucose depletion of erythrocytes triggers suicidal erythrocyte death or eryptosis, which leads to cell membrane scrambling with phosphatidylserine exposure at the cell surface. Eryptotic erythrocytes adhere to endothelial cells by a mechanism involving phosphatidylserine at the erythrocyte surface and CXCL16 as well as CD36 at the endothelial cell membrane. Nothing has hitherto been known about an interaction between eryptotic erythrocytes and platelets, the decisive cells in primary hemostasis and major players in thrombotic vascular occlusion. The present study thus explored whether and how glucose-depleted erythrocytes adhere to platelets. To this end, adhesion of phosphatidylserine-exposing erythrocytes to platelets under flow conditions was examined in a flow chamber model at arterial shear rates. Platelets were immobilized on collagen and further stimulated with adenosine diphosphate (ADP, 10 µM) or thrombin (0.1 U/ml). As a result, a 48-h glucose depletion triggered phosphatidylserine translocation to the erythrocyte surface and augmented the adhesion of erythrocytes to immobilized platelets, an effect significantly increased upon platelet stimulation. Adherence of erythrocytes to platelets was blunted by coating of erythrocytic phosphatidylserine with annexin V or by neutralization of platelet phosphatidylserine receptors CXCL16 and CD36 with respective antibodies. In conclusion, glucose-depleted erythrocytes adhere to platelets. The adhesive properties of platelets are augmented by platelet activation. Erythrocyte adhesion to immobilized platelets requires phosphatidylserine at the erythrocyte surface and CXCL16 as well as CD36 expression on platelets. Thus platelet-mediated erythrocyte adhesion may foster thromboocclusive complications in diseases with stimulated phosphatidylserine exposure of erythrocytes.

Sphingosine kinase 1 (Sphk1) negatively regulates platelet activation and thrombus formation.

Sphingosine 1-phosphate (S1P) is a powerful regulator of platelet formation. Enzymes generating S1P include sphingosine kinase 1. The present study thus explored the role of sphingosine kinase 1 in platelet formation and function. Activation-dependent platelet integrin αIIbß3 activation and secretion of platelets lacking functional sphingosine kinase 1 (sphk1(-/-)) and of wild-type platelets (sphk1(+/+)) were determined utilizing flow cytometry and chronolume luciferin assay. Cytosolic Ca(2+) activity ([Ca(2+)]i) and aggregation were measured using fura-2 fluorescence and aggregometry, respectively. In vitro platelet adhesion and thrombus formation were evaluated using a flow chamber with shear rates of 1,700 s(-1). Activation-dependent increase of [Ca(2+)]i, degranulation (release of alpha and dense granules), integrin αIIbß3 activation, and aggregation were all significantly increased in sphk1(-/-) platelets compared with sphk1(+/+) platelets. Moreover, while platelet adhesion and thrombus formation under arterial shear rates were significantly augmented in Sphk1-deficient platelets, bleeding time and blood count were unaffected in sphk1(-/-) mice. In conclusion, sphingosine kinase 1 is a powerful negative regulator of platelet function counteracting degranulation, aggregation, and thrombus formation.