Aim: We aimed to assess the importance of abdominal ultrasound in detecting colon cancer,
comparatively with endoscopic exam. We present our ten-year experience with abdominal
ultrasound in patients with suspected colon cancer.
Colon cancer is one of the main causes of cancer death. Diagnosis requires the examination
of the entire large bowel by means of radiological or endoscopic techniques.
Ultrasound is complementary to colonoscopy and it offers subtle information on colon
wall structure. Colon and gastric ultrasound images are constant ultrasound elements
and we have to learn to recognize them. Being non-invasive, cheap, with high accessibility
and addressability, ultrasound must be utilized as a first intention exam.
Material and methods: We included 322 patients with suspected colon cancer (mean age 62 years, 214 men)
examined between 1997 and 2007. We performed abdominal ultrasound and hydrocolonoscopy;
all patients underwent conventional preparation consisting of liquid diet the afternoon
before the procedure, and three enemas, two the previous night and another in the
morning of the examination. The ultrasound was considered positive when the characteristic
image of hypoechoic thickening with loss of mobility and of stratification in layers
of the wall was observed. All patients were remitted consecutively to the endoscopy
unit for colonoscopy.
Results: In 137 (42.54%) cases the colonoscopy established the diagnosis. Abdominal ultrasound
had a sensitivity of 82.48% and a specificity of 93.4%. The positive predictive value
was 84.6% and the negative predictive value was 93.5%.
Conclusions: Abdominal ultrasound is a first intention exam in patients with suspected colon cancer.
Abdominal sonography represents a specific and sensitive technique in the detection
of colon cancer. It is a simple technique that is very well tolerated by the patients
and risk-free. It could be an alternative to the conventional radiological and endoscopic
tests when these techniques are not possible and in those patients in which the diagnosis
is not clear.
