Characterization and differentiation of three solid tumors using quantitative ultrasound

Abstract

Three kinds of solid tumors were acquired and scanned in vivo ultrasonically. The first tumor series (fibroadenoma) was acquired from tumors that had spontaneously developed in rats. The second tumor series was acquired by culturing a carcinoma cell line (4T1-MMT) in culture media and injecting the cells into Balb/c mice. The third tumor was acquired by transplanting a soft-tissue sarcoma cell line (EHS) into C57BL mice. The tumors were allowed to grow to 1 cm in size and then scanned ultrasonically. The scatterer properties of average scatterer diameter and acoustic concentration were estimated using a Gaussian form factor from the backscattered ultrasound measured from the tumors. Parametric images of the tumors were constructed utilizing estimated scatterer properties for regions of interest inside the tumors. The parametric images showed distinct differences between the various tumor types. Quantitatively, the tumors could be distinguished through feature analysis plots of average scatterer size versus acoustic concentration. Comparison with photomicrographs of the tumors showed structures similar in size to the ultrasound estimates. [Work supported by NIH Grant F32 CA96419 to MLO and by the University of Illinois Research Board.]