Bowel mass- sigmoid carcinoma:

This middle aged male adult patient has a mass just above the urinary bladder. Ultrasound video clip of the mass is seen in sagittal section:

The mass shows an echogenic central area with hypoechoic, surrounding soft tissue area. This is called the "target sign" and is typical of colonic malignancy.

 Yet another sagittal ultrasound video clip shows the mass with the thickened sigmoid colon walls. Also note the absence of normal layered appearance of the normal large bowel.

This color Doppler ultrasound video shows the sigmoid colon mass to be poorly vascular. The mass has all the appearances of a sigmoid carcinoma.

 The close proximity of the mass to the urinary bladder (upper pelvis) and target sign are an indication of the mass originating from the sigmoid colon. The liver appeared normal. Close follow up and CT scan imaging are needed to rule out lymph node spread.
See more ultrasound images and description of this case at:
http://www.ultrasound-images.com/colon.htm
http://emedicine.medscape.com/article/367061-imaging