Accuracy of Endoscopic Ultrasound for Detection of Tumors of the Liver - A Prospective Study

The incidence of hepatocellular carcinoma is increasing in US. The reason for this increase has been attributed to the emergence of hepatitis C. Studies suggest that patients with hepatitis C are at higher risk of developing hepatocellular carcinoma (elevated alpha-fetoprotein) and, therefore should undergo periodic radiological investigation.

The liver is also a common site for metastases for various malignancies. The metastasis to liver profoundly affects the management and prognosis, since these patients have advanced cancer and therefore are not candidates for surgery.

1.1 Current standards of care

For primary liver tumors alpha-fetoprotein, abdominal ultrasound and CT scan of the abdomen are the suggested tests for the screening in patients that are at higher risk of developing this complication. Measurement of serum alpha-fetoprotein (AFP) may be helpful in the diagnosis and management of HCC. AFP is elevated above 20 ng/Ml in more than 70% of patients with HCC. However, AFP elevations from 10-500 ng/Ml and even occasionally to 1000 ng/ml may be seen in patients with a high degree of inflammatory activity such as with chronic viral hepatitis, who do not have HCC (3). The sensitivity, specificity, and positive predictive value of AFP in 3 well performed screening studies for HCC ranged from 39%-64%, 76%-91%, and 9%-32%, respectively (4). Imaging studies play a key role in the diagnosis of HCC since a significant number of cases are missed by AFP. CT scan and magnetic resonance imaging are commonly used tests.

On the basis of studies conducted over last two decades, National Comprehensive Cancer Network (2004) guidelines for the management of cancer recommended CT scan for the evaluation of the liver for metastases (Please refer to appendix III).