In vitro correlation of echogenicity and differential echogenicity with human prostate cancer grade

Results are presented from an ongoing project at the University of Missouri-Columbia (MU) which focuses on the detection, grading, and staging of prostate cancer. The study addressed in this paper was performed in vitro using human prostates obtained from radical prostatectomies. Each prostate was transversely sectioned to extract a 2 mm slice which was then ultrasonically scanned. Cancerous and benign regions of the prostate were subsequently identified on the tissue slice by a pathologist. This scanning and analysis procedure allowed for a one-to-one correlation of actual tissue histopathology and acoustic parameter images. Echogenicity and differential echogenicity measures were calculated based on integrated backscatter, backscattered power spectra, and backscatter coefficient. Of these measures, only the backscatter coefficient, which was corrected for spatial variations in attenuation, showed a statistically significant trend with cancer grade. This trend suggests a new result which is that the inherent echogenicity of cancerous tissue decreases with increasing cancer grade.