Abstract

Core needle biopsy (CNB) was widely used in the diagnosis of ultrasound-detectable breast lesions. We aimed at assessing the diagnostic performance differences between 14- and 16-gauge ultrasound-guided core biopsies. This retrospective study enrolled patients receiving CNB from January 2001 to December 2007. The results of 14- and 16-gauge breast CNBs were compared with pathology reports of open surgical biopsy (OSB). A total of 1024 paired CNB and OSB results were obtained from 1732 CNB procedures in 1630 patients.Those CNB results reached 92.9% sensitivity, 99.7% specificity, 5.96% underestimation, and 94.8% accuracy rates. There was no difference in sensitivity (p = 0.17) or specificity (p = 0.38) between 14- and 16-gauge needles. However, better overall accuracy (p = 0.02), less underestimation (p < 0.001), and lower false-negative (p = 0.02) rates were found for the 14-gauge CNB. Regarding accuracy and underestimation rates, a 14-gauge needle is preferred to a 16-gauge one in ultrasound-guided biopsies.

Abstract

Primary squamous cell carcinoma of the breast (SCCB) is a rare disease, with a worldwide incidence <0.1%. In many cases, it is clinically characterized by rapid growth. Cyst formation due to central necrosis of the tumor accompanies its growth of the tumor in approximately 60–80% of all cases. Furthermore, it is considered difficult to diagnose SCCB solely on the basis of findings from diagnostic imaging. For large intracystic tumors, mammotome biopsy or core needle biopsy (CNB) is rarely performed. Instead, fine-needle aspiration (FNA) targeted at the tumor inside the cyst is often performed. The accurate diagnosis rate of SCCB using FNA is lower than that for ordinary-type breast cancer. If the cyst is large, the solid tumor shadow outside the cyst behind or around the cyst may be masked or hidden by the large cyst, which can sometimes yield an unclear view of the tumor shadow or make it impossible to visualize the shadow. In the present case, the contents within the cyst were completely aspirated and collected during the first step (FNA), thereby yielding a clearer, complete view of the solid tumor located outside the cyst. Thus, the subsequent step (CNB) was able to be performed in a more accurate and reliable manner. The combined use of FNA and CNB proved to be useful in making a preoperative diagnosis of SSCB accompanying a cyst.