Diagnostic value of a power Doppler ultrasound-based malignancy index for differentiating malignant and benign solid breast lesions.

BACKGROUND: Power Doppler ultrasound (PDUS) can provide useful information regarding the vascularity of breast lesions. The aim of this study was to investigate the diagnostic performance of a new PDUS-driven malignancy index in differentiating between malignant and benign causes of solid breast lesions. MATERIALS AND METHODS: Patients with solid breast lesions were enrolled consecutively and evaluated first by PDUS and subsequently by histopathologic assessment after undergoing surgical biopsy. A custom-made software was used to extract data from images for calculating malignancy index formula. RESULTS: A total of 87 patients with solid breast lesions were enrolled. Histopathologic evaluation identified 49 patients as benign and 38 patients as malignant. Malignancy index was significantly higher in the malignant group as compared to benign tumors (6.31 vs 0.30,P < 0.001). Area under the receiver operating characteristics (ROC) curve (AUC) was 0.98 (95% confidence interval (CI) 0.95-1.00). According to the ROC curve analysis, the cut-off point of 1.23 for malignancy index had a sensitivity and specificity of 94.7% (95% CI 82.2-99.3) and 94.0% (95% CI 83.1-98.7), respectively. CONCLUSION: Comparing with the histopathologic evaluation as the gold standard for diagnosing breast lesions, PDUS-driven malignancy index was shown to have a high discriminative performance in identifying malignant lesions with high sensitivity, specificity, and diagnostic accuracy. The noninvasive nature of PDUS is an important advantage that could prevent unnecessary biopsies.

A novel computerised quantification of thyroid vascularity in the differentiation of malignant and benign thyroid nodules.

PURPOSE: Only five percent of thyroid nodules are malignant. It is important to find reliable and at the same time non-invasive methods to identify high-risk nodules. The aim of this study was to determine the diagnostic validity of a morphologic feature-oriented approach of ultrasound study for the identification of malignant thyroid nodules. MATERIAL AND METHODS: Seventy-one thyroid nodules in 71 consecutive patients were evaluated with both ultrasonography (US) and US-assisted fine needle aspiration biopsy (FNAB). Thyroid grey-scale and power Doppler US were performed, and a Windows-based software was designed to process power Doppler US (PDUS) images that were recorded directly by the US device. We provided a histogram graph of coloured pixels and calculated the Malignancy Index to identify the probability of malignancy for each thyroid nodule. RESULTS: Thirty-six nodules (50.7%) were determined to be malignant in FNAB. Area under the receiver operating curve was 0.91 (95% CI: 0.85-0.98) for PDUS-based malignancy index in differentiating malignant thyroid nodules from benign ones. The best cut-off point for malignancy index was determined to be 0.092, with a sensitivity of 86.1% and specificity of 80% in identifying malignant nodules. CONCLUSIONS: This PDUS-driven malignancy index using a contour-finding algorithm approach could accurately and reliably differentiate malignant and benign thyroid nodules. As a pre-FNAB assessment, the malignancy index may be able to reduce the number of patients with nodular thyroid disease undergoing this invasive procedure.