Measuring tumor perfusion in control and treated murine tumors: correlation of microbubble contrast-enhanced sonography to dynamic contrast-enhanced magnetic resonance imaging and fluorodeoxyglucose positron emission tomography.

OBJECTIVE: The purpose of this study was to evaluate the ability of dynamic microbubble contrast-enhanced sonography (MCES), in comparison with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and fluorodeoxyglucose positron emission tomography (FDG-PET), to quantitatively characterize tumor perfusion in implanted murine tumors before and after treatment with a variety of regimens. METHODS: Seventeen mice with Lewis lung carcinoma implants were categorized to control, radiation therapy alone, antiangiogenic chemotherapy alone, and combined chemoradiation. On day 0 of each treatment regimen, MCES and DCE-MRI of each tumor were performed. On day 5 of treatment, dynamic FDG-PET, MCES, and DCE-MRI were performed. RESULTS: Microbubble contrast-enhanced sonography showed that intratumoral perfusion, blood volume, and blood velocity were highest in the untreated control group and successively lower in each of the treatment groups: radiation therapy alone resulted in a two-thirds reduction of perfusion; antiangiogenic chemotherapy resulted in a relatively larger reduction; and combined chemoradiotherapy resulted in the largest reduction. Microbubble contrast-enhanced sonography revealed longitudinal decreases in tumor perfusion, blood volume, and microvascular velocity over the 5-day course of chemoradiotherapy (all P < .01); conversely, these values rose significantly for the untreated control tumors (P < .01). Dynamic contrast-enhanced MRI showed a smaller and statistically insignificant average decrease in relative tumor perfusion for treated tumors. Dynamic PET revealed delayed uptake of FDG in the tumors that underwent chemoradiotherapy. CONCLUSIONS: Microbubble contrast-enhanced sonography is an effective tool in the noninvasive, quantitative, longitudinal characterization of neovascularization in murine tumor models and is correlative with DCE-MRI and FDG-PET. Microbubble contrast-enhanced sonography has considerable potential in the clinical assessment of tumor neovascularization and in the assessment of the response to treatment.

Sonographic quantification of ovarian tumor vascularity.

OBJECTIVE: The purpose of this study was to assess the diagnostic accuracy of quantitated color Doppler sonography in differentiating benign from malignant ovarian tumors, with the use of tumor histologic examination as a reference standard. METHODS: The vascularity of 38 ovarian masses (30 benign and 8 malignant) as quantitatively depicted with color Doppler sonography was analyzed with a readily available software program (ImageJ; National Institutes of Health, Bethesda, MD). The following quantitative sonographic criteria for tumor vascularity were analyzed: the vascularity index (VI) quantified the difference between the total number of pixels and the number of pixels containing no color/totalx100, whereas the power-weighted pixel density (PWPD) weighted the strength of the signal/total. The accuracy of sonographic criteria for malignant ovarian tumors was evaluated with univariate analysis. Results of tumor histologic examination were used as proof of the final diagnosis. RESULTS: The mean values of VI and PWPD were significantly different in benign versus malignant ovarian lesions (VI, 1.3+/-1.6 versus 4.7+/-3.9; P<.01; PWPD, 2338+/-3305 versus 9403+/-9946; P<.05). With a VI of greater than 2.3, sensitivity of 75% and specificity of 90% were obtained. When combined with a PWPD of greater than 4555, sensitivity improved to 88%, and specificity improved to 93%. Morphologic analysis had sensitivity of 72% and specificity of 76% for malignancies. CONCLUSIONS: Quantitated color Doppler sonography was found to be helpful for distinguishing benign from malignant ovarian masses. However, the wide range in values makes it most useful as an adjunct to morphologic assessment. It is anticipated that quantitated color Doppler sonography could result in a slight improvement in detection of ovarian malignancies.