Color Doppler ultrasound in benign and malignant breast tumors.

To study the flow indices of color Doppler ultrasound in the differentiation of malignant and benign breast tumors, data of 1124 female patients with breast lesions were analyzed. Of 1124 breast lesions, 590 (525%) were benign and 534 (47.5%) were malignant. Color Doppler scanning detected vascularity in 505 (85.6%) of benign lesions and 509 (95.3%) of malignant tumors. The tumors without detectable vascularization (1.9 +/- 0.1 cm) were significantly (p < 0.0001) smaller than the tumors with vascularization (2.7 +/- 0.1 cm). The age of the patients with malignant tumors was older than that of the patients with benign lesions. The size of malignant tumors was significantly larger than that of benign lesions. Significantly higher values of vessel number, resistance index (RI), pulsatility index (PI), and systolic peak flow velocity (Vmax) were found in carcinomas but the striking overlap of the values did not allow defining cutoff values which allow an accurate differentiation. Vmax did not correlate with the size of tumors. When tumors were grouped as T1 (2 cm or less), T2 (>2 cm, but not >5 cm), and T3 (>5 cm), the results were similar to those of all breast tumors. In conclusion, number of vessels, RI, PI, and Vmax do not provide accurate differentiation of benign and malignant tumors. However, average values of these flow indices of malignant tumors were significantly larger than those of benign lesions. Tumors with larger values of vessel number, RI, PI or Vmax require further studies to disclose the possibility of malignant tumors.