Tumors of the liver and subhepatic region

Tumors of the liver and subhepatic region often have unfavorable prognosis. The tumors of the subhepatic region include tumors of the bile ducts, gallbladder and the head of the pancreas.

Tumors of the liver
It can be classified into two categories:


 * Primary (benign or malignant)
 * Secondary (metastases - mainly originating from the gastrointestinal tract)

Pathological classification
According to the tissue from which the liver tumors originate, benign tumors of the liver could be divided into epithelial, mesenchymal and mixed.

Epithelial tumors


 * Hepatocellular - nodular transformation, focular nodular hyperplasia, hepatocellular adenoma
 * Cholangiocellular - gallbladder adenoma, biliary cystadenoma


 * Mesenchymal tumors
 * Mesenchymal tumors

This group includes tumors arising from the interstitium and perivascular tissues:


 * Lipoma
 * Myelolipoma
 * Angiolipoma
 * Leiomyoma

Mixed tumors
 * Mesenchymal hamartoma (= noncancerous tumor-like malformation composed of an abnormal mixture of cells and tissue)
 * Benign teratoma (= tumor consisting of several different kinds of tissue, such as teeth, bone, hair or muscle; most common sites are the ovaries, testicles and the coccyx bone)

Hepatic hemangioma
Hepatic hemangiomas are the most common type of benign tumors of the liver, composing of clusters of blood-filled cavities that are lined by endothelial cells and supplied by the hepatic artery. The patients are often asymptomatic, therefore the discoveries of hepatic hemangiomas are mostly accidental - from imaging methods for other pathologies. Biopsies are not performed because there is risk of massive bleeding.

The hepatic hemangiomas could be of varying sizes:


 * Small - from mm up to 3 cm
 * Medium - 3 cm to 10 cm
 * Giant - could be larger than 10 cm

Therapy

Small and medium lesions are conservatively treated, with regular monitoring. Larger lesions, however, could progress with complications and symptoms that could need futher therapies or surgical intervention.

Focal nodulation hyperplasia
Focal nodulation hyperplasia (FNH) is the second most common type of benign liver tumor. It is difficult to distinguish from malignant tumors, macroscopically and microscopically. It could be made up of an accumulation of hepatocytes, Kupffer cells and small bile ducts with congestion of the fibrous septa. FNH occurs 2-8 times more often in women, usually in individuals between 20-50 years old, which suggests relationship with increased estrogen levels. The probability of occurrence increases significantly in puberty and pregnancy, due to its association with hormonal influences and the use of hormonal contraception.

Clinical picture


 * Does not manifest itself, usually discovered by accident
 * Approximately 80% of cases does not exceed 5 cm in size
 * Larger ones may manifest as other tumors

Diagnostics

Ultrasound, CT and scintigraphy are used for diagnosis; biopsy could be used for confirmation

Treatment

Usually FNH is treated conservatively and monitored regularly every 3 to 6 months. However, in the case that the patient is symptomatic, if there is inconclusive biopsy findings or if there is suspicion for malignancy, resection could be considered.

Hepatic adenoma
Liver adenoma or hepatocellular adenoma is a rare type of benign liver tumor. It is also associated with the use of oral contraceptives, mainly affecting women aged between 30 to 40 years of age. In 30% of the cases, it involves perforation and hemorrhage could occurs.

Therapy

For lesions smaller than 5 cm, treatment usually follows the conservative approach. On the other hand, larger lesions greater than 5 cm could increase the susceptibility to hemorrhage or transformation into malignancy, thus resections are preferred.

Malignant tumors
Malignant tumors of the liver could also be divided into primary and secondary. These include hepatocellular carcinoma, fibrolamellar carcinoma, cholangiocarcinoma, hepatoblastoma, mesenchymal malignancies (angiosarcoma, fibrosarcoma) and others (for example carcinoid).

Hepatocellular carcinoma
Hepatocellular carcinoma (HCC) is the most common primary malignant liver tumor. Hepatocellular carcinoma is the fifth most common tumor in men and eighth in women worldwide. The development of this cancer occurs most often in patients with chronic liver disease, usually involving cirrhosis of various etiologies (alcohol abuse, chronic hepatitis B and hepatitis C). Hepatocellular carcinoma is the third leading cause of death worldwide. The only potentially curative therapy is surgical treatment (resection or transplantation).

Fibrolamellar carcinoma
Highly differentiated hepatocellular carcinoma. It is difficult to distinguish from adenoma and nodular hyperplasia. He usually has cirrhosis. It is usually 75% resectable, so it has a better prognosis.

Cholangiogenic carcinoma
It affects the intrahepatic bile ducts. It rarely manifests as inflammation of the bile ducts. It is more common in primary sclerosing cholangitis. The main manifestation is jaundice. The prognosis is often poor, the tumor is usually detected when it is unresectable.

Liver metastases
CT of liver and spleen metastases Liver metastases of pancreatic cancer.

Metastases cause up to 90% of liver malignancies. In 20% they are metastases from gastric cancer, 25% from colons, in 50% they are metastases from pancreatic cancer. In solitary and innumerable (up to 3) there is an indication of anatomical and non-anatomical resection (mainly in colorectal cancer ).

Conservative
It is mainly used for metastases from colorectal cancer and breast cancer, unless cirrhosis is significant:


 * cholecystectomy (prophylaxis of toxic cholecystitis), gastroduodenal probing and catheter insertion,
 * discontinuation of contraception or estrogen preparations in adenoma if the adenoma does not subside → surgery,
 * multiple liver metastases are treated with local intraarterial CHT (via hepatic artery ) by subcutaneously implanted port system for 14 days, the treatment has only a minimal systemic effect.

Surgical
Surgical treatment is indicated for benign tumors (adenomas, bleeding tumors or large hemangiomas) and some malignancies. The tumor must be bounded to one lobe (T1 – T3).

Surgery is the only treatment option, only 20% of patients are curatively operable (late onset of symptoms). We use the following approaches:


 * transverse or medial laparotomy, or incision along the arch,
 * hemihepatectomy - is oriented in the line vena cava - gallbladder,
 * extended hemihepatectomy on the right - according to the ligamentum falciforme hepatis,
 * resection of the liver lobe on the left - left lobe up to the lig. falciforme,
 * peripheral resection.


 * Liver metastases

Peripheral resection without orientation according to anatomical structures. The ultima ratio indicates liver transplantation in hepatocellular carcinoma if it has not yet metastasized.