3 Diagnostic studies
In cirrhotic patients, HCC may be associated with abnormal liver function tests due to hepatitis. Elevated serum α-fetoprotein (AFP) occurs in 75% of affected African patients but in only 30% of patients in the United States. AFP is also often elevated in chronic hepatitis and cirrhosis. A level greater than 200 ng/mL (normal <20 ng/mL) is suggestive of HCC, even in the cirrhotic patient.
Radiologic studies FOR Hepatocellular carcinoma
a) Ultrasonography can be highly accurate in the detection of HCC, especially when coupled with concomitant AFP elevations.
b) MR scan can be useful in differentiating other small nodular masses from Hepatocellular carcinoma. This is the most accurate imaging modality for distinguishing HCC from dysplastic or regenerative nodules in the cirrhotic patient.
c) Multiphasic CT scan with arterial and portal venous phase contrast imaging can distinguish among different types of liver masses. HCC Hepatocellular carcinoma enhances in the arterial and not usually in the portal venous phase. Washout of contrast in the delayed (portal venous) phases of enhancement is an additional characteristic of Hepatocellular carcinoma HCC. Washout is defined as hypointensity of a nodule in the delayed phase compared with surrounding liver parenchyma. It is thought to be due to greater arterial neovascularization in HCC lesions than in the adjacent normal parenchyma; thus, in the portal venous phase, there is early venous drainage. A mass in a cirrhotic liver that manifests arterial enhancement with washout has a sensitivity of about 80% with specificity of 95% to 100%. The sensitivity of CT may also be enhanced with lipiodol (a lipid lymphographic agent that is selectively retained in HCC) when this is injected 2 hours before the imaging examination.
d) When required, laparoscopic or image-guided percutaneous biopsies may be used to obtain a tissue diagnosis. However, a tissue diagnosis is not required before therapeutic intervention (including surgical extirpation and liver transplantation) if other diagnostic modalities favor Hepatocellular carcinoma HCC as the diagnosis. Unresectable tumors likewise usually do not require biopsy to confirm the diagnosis because imaging and laboratory studies allow a definitive diagnosis in the majority of cases.
Several staging systems for HCC have been proposed. The most commonly used in the United States is the TNM classification. The individual TNM (tumor, nodes, and metastases) stages are grouped into overall stages: T1 to T4 with N0M0 correspond to stages I, II, IIIA, and IIIB, respectively, whereas N1M0 with any T stage is stage IIIC, and M1 disease is designated stage IV.