Liver Tumors

Benign Tumors

Hemangioma, the most common benign liver tumor, is found in about 5% of adults at autopsy. Other benign tumors include adenoma and focal nodular hyperplasia, which are most often associated with oral contraceptive use and do not usually occur in the elderly.

Benign tumors are generally asymptomatic and are found incidentally when a CT or ultrasound is performed for unrelated symptoms. Liver function test results are typically normal. Diagnosis is established by ultrasound, dynamic CT, or MRI. Labeled erythrocyte scintigraphy or angiography may help diagnose vascular lesions. Cytohistologic diagnosis is confirmed by fine-needle biopsy in nonvascular lesions. Therapy for nonvascular tumors usually consists of segmental resection. Hemangiomas usually require no treatment.

Malignant Tumors

Metastatic carcinoma is by far the most common form of liver cancer. The liver is the most common site of metastasis from other cancers. Hepatic metastases are found at autopsy in 30 to 50% of cancer patients.

Hepatocellular carcinoma is one of the most common cancers worldwide, particularly in areas with a high incidence of viral hepatitis. In the USA, the incidence is 2 per 100,000, but incidence has been increasing over the past 2 decades, significantly among persons 40 to 60. This tumor originates in the hepatocyte and accounts for > 90% of primary adult hepatic cancers. Cholangiocarcinoma (lesions originating in the bile ducts) represents the remaining 5 to 10%. Hepatic malignancies are more common in men than in women and occur between ages 50 and 70.

In most cases, the tumor develops in the setting of cirrhosis, mainly related to hepatitis B and C virus infection. Recently, hepatitis C virus infection has emerged as the leading identifiable risk factor for hepatocellular carcinoma. Therefore, cirrhotic patients constitute the population at risk; the 5-year probability of these patients developing a hepatocellular carcinoma is about 20%. Other predisposing factors include alcohol, tobacco, and aflatoxin exposure.

Symptoms and Signs

Only 20% of cases are asymptomatic at the time of diagnosis. Hepatocellular carcinoma usually presents as decompensated liver disease (ie, ascites, hepatic encephalopathy, jaundice, variceal bleeding) in persons with cirrhosis. Right upper quadrant or epigastric pain and weight loss are also common. Intra-abdominal hemorrhage due to tumor rupture is rare but life threatening.

Physical examination may reveal hepatomegaly, a right upper quadrant mass, ascites, or jaundice. Splenomegaly is less common. Paraneoplastic syndromes associated with hepatocellular carcinoma include erythrocytosis, hypercalcemia, hypoglycemia, hyperlipidemia, porphyria cutanea tarda, and dysfibrinogenemia.

Diagnosis

Liver function test results are usually abnormal, with increased serum bilirubin levels, elevated serum alkaline phosphatase and g-glutamyl transpeptidase levels, and diminished serum albumin concentration. The serum -fetoprotein level alone is not useful for early detection.

Diagnosis is often made with a combination of abdominal ultrasound and CT, angiography, and biopsy. Periodic ultrasound seems to be the most adequate screening strategy in high-risk populations (ie, patients with liver cirrhosis) combined with the -fetoprotein level.

Prognosis and Treatment

Prognosis in patients with hepatocellular carcinoma is determined by the tumor stage and by the liver's functional status. The 5-year survival of selected patients treated by surgical resection or liver transplantation is > 50%.

Surgical resection is usually restricted to patients with solitary tumors without vascular invasion or extrahepatic spread. Extensive lobectomies are contraindicated in cirrhotic patients, and segmentary or subsegmentary resection should be the goal. In the elderly, data regarding liver surgery are limited to major resection for colorectal metastases; thus, it is difficult to infer the results of this procedure in patients with hepatocellular carcinoma associated with liver cirrhosis.

Liver transplantation may be curative for hepatocellular carcinoma, especially when performed in persons with small solitary tumors; the recurrence rate is negligible and survival is similar to patients undergoing transplantation for nonmalignant causes. Nevertheless, most centers will not perform liver transplantation in patients >= 65, especially with coexisting comorbid illnesses.

Percutaneous hepatic injection with ethanol has gained wide popularity, especially in Japan and Europe. Absolute ethanol is injected through a fine needle into the tumor under ultrasound control, inducing complete necrosis. This procedure is well tolerated and is highly effective for solitary tumors < 4 cm; complications are very rare. In patients with these lesions, the probability of recurrence and survival is almost the same as that obtained by surgical resection. Other options include tumor embolization or chemoembolization, systemic chemotherapy, hormonal manipulation, and immunotherapy. Although some of these treatments have a relatively high antitumor effect, a beneficial effect on survival has not been clearly established.

Like patients with pancreatic cancer, those with liver cancer often present in an advanced stage. Death and dying issues must be addressed for many patients. Attention must be paid to quality of life, especially nutritional status and pain relief.