Cancer of the Liver
Hepatic tumors may be malignant or benign. Benign liver tumors were uncommon until the widespread use of oral contraceptives. With the use of oral contraceptives, benign tumors of the liver occur most frequently in women in their reproductive years.
Few cancers originate in the liver. Primary liver tumors usually are associated with chronic liver disease, hepatitis B and C infections, and cirrhosis. Hepatocellular carcinoma (HCC) is by far the most common type of primary liver cancer, but it is rare in the United States (Bacon & Di Bisceglie, 2000). HCC is usually nonresectable because of rapid growth and metastasis. Other types of primary liver cancer include cholangiocellular carcinoma and combined hepatocellular and cholangiocellular carcinoma. If found early, resection may be possible, but early detection is unlikely. Cir-rhosis, chronic infection with hepatitis B and C, and exposure to certain chemical toxins (eg, vinyl chloride, arsenic) have been im-plicated as causes of HCC. Cigarette smoking has also been iden-tified as a risk factor, especially when combined with alcohol use. Some evidence suggests that aflatoxin, a metabolite of the fungus Aspergillus flavus, may be a risk factor for HCC. This is especiallytrue in areas where HCC is endemic (ie, Asia and Africa). Afla-toxin and other similar toxic molds can contaminate food such as ground nuts and grains and may act as a co-carcinogen with he-patitis B. The risk of contamination is greatest when these foods are stored unrefrigerated in tropical or subtropical climates.
Metastases from other primary sites are found in the liver in about half of all advanced cancer cases (Bacon & Di Bisceglie, 2000). Malignant tumors are likely to reach the liver eventually, by way of the portal system or lymphatic channels, or by direct extension from an abdominal tumor. Moreover, the liver apparently is an ideal place for these malignant cells to thrive. Often the first evi-dence of cancer in an abdominal organ is the appearance of liver metastases; unless exploratory surgery or an autopsy is performed, the primary tumor may never be identified.
The early manifestations of malignancy of the liver include pain, a continuous dull ache in the right upper quadrant, epigastrium, or back. Weight loss, loss of strength, anorexia, and anemia may also occur. The liver may be enlarged and irregular on palpation. Jaundice is present only if the larger bile ducts are occluded by the pressure of malignant nodules in the hilum of the liver. As-cites develops if such nodules obstruct the portal veins or if tumor tissue is seeded in the peritoneal cavity.
The liver cancer diagnosis is based on clinical signs and symp-toms, the history and physical examination, and the results of laboratory and x-ray studies. Increased serum levels of bilirubin, alkaline phosphatase, AST, GGT, and lactic dehydrogenase may occur. Leukocytosis (increased white blood cells), erythrocytosis (increased red blood cells), hypercalcemia, hypoglycemia, and hypocholesterolemia may also be seen on laboratory assessment.
The serum level of alpha-fetoprotein (AFP), which serves as a tumor marker, is elevated in 30% to 40% of patients with pri-mary liver cancer. Levels of carcinoembryonic antigen (CEA), a marker of advanced cancer of the digestive tract, may be elevated. These two markers together are useful to distinguish between metastatic liver disease and primary liver cancer.
Many patients have metastases from the primary liver tumor to other sites by the time diagnosis is made; metastases occur pri-marily to the lung but may also occur to regional lymph nodes, adrenals, bone, kidneys, heart, pancreas, and stomach.
X-rays, liver scans, CT scans, ultrasound studies, MRI, arterio-graphy, and laparoscopy may be part of the diagnostic workup and may be performed to determine the extent of the cancer. Pos-itive emission tomograms (PET scans) are used to evaluate a wide range of metastatic tumors of the liver.
Confirmation of a tumor’s histology can be made by biopsy under imaging guidance (CT scan or ultrasound) or laparoscop-ically. Local or systemic dissemination of the tumor by needle biopsy or fine-needle biopsy can occur but is rare. Some clini-cians believe that these procedures should not be performed if the tumor is thought to be resectable; rather, for primary HCC diagnosis should be confirmed by frozen section at the time of laparotomy.
Although surgical resection of the liver tumor is possible in some patients, the underlying cirrhosis, so prevalent in cancer of the liver, increases the risks associated with surgery. Radiation ther-apy and chemotherapy have been used in treating cancer of the liver with varying degrees of success. Although these therapies may prolong survival and improve quality of life by reducing pain and discomfort, their major effect is palliative.
The use of external beam radiation for the treatment of liver tumors has been limited by the radiosensitivity of normal hepatocytes. Doses over 2,500 to 3,000 cGy may result in radiation hepati-tis (O’Grady et al., 2000). More effective methods of delivering radiation to tumors of the liver include (1) intravenous or intra-arterial injection of antibodies that are tagged with radioactive isotopes and specifically attack tumor-associated antigens and (2) percutaneous placement of a high-intensity source for in-terstitial radiation therapy (delivering radiation directly to the tumor cells).
Chemotherapy has been used to improve quality of life and pro-long survival; it also may be used as adjuvant therapy after sur-gical resection of hepatic tumors. Systemic chemotherapy and regional infusion chemotherapy are two methods used to admin-ister antineoplastic agents to patients with primary and metasta-tic hepatic tumors (O’Grady et al., 2000).
An implantable pump has been used to deliver a high concen-tration of chemotherapy to the liver through the hepatic artery. This method provides a reliable, controlled, and continuous infusion of medication that can be carried out in the patient’s home. Re-cent studies have begun to show some effective palliation and modestly improved survival rates (Bacon & Di Bisceglie, 2000).
Percutaneous biliary or transhepatic drainage is used to bypass biliary ducts obstructed by liver, pancreatic, or bile duct tumors in patients with inoperable tumors or in those considered poor surgical risks. Under fluoroscopy, a catheter is inserted through the abdominal wall and past the obstruction into the duode-num. Such procedures are used to reestablish biliary drainage, relieve pressure and pain from the buildup of bile behind the obstruction, and decrease pruritus and jaundice. As a result, the patient is made more comfortable and quality of life and sur-vival are improved.
For several days after its insertion, the catheter is opened to ex-ternal drainage. The bile is observed closely for amount, color, and presence of blood and debris. Complications of percutaneous biliary drainage include sepsis, leakage of bile, hemorrhage, and reobstruction of the biliary system by debris in the catheter or from encroaching tumor. Therefore, the patient is observed for fever and chills, bile drainage around the catheter, changes in vital signs, and evidence of biliary obstruction, including increased pain or pressure, pruritus, and recurrence of jaundice.
Laser hyperthermia has been used to treat hepatic metastases. Heat has been directed to tumors through several methods to cause necrosis of the tumor cells while sparing normal tissue. In radio-frequency thermal ablation, a needle electrode is inserted into the liver tumor under imaging guidance. Radiofrequency energy passes through to the noninsulated needle tip, causing heat and tumor cell death from coagulation necrosis.
Immunotherapy is another treatment modality under investi-gation. In this therapy, lymphocytes with antitumor reactivity are administered to the patient with hepatic cancer. Regression of the tumor, the desired outcome, has been demonstrated in patients with metastatic cancer in whom standard treatment has failed.
Transcatheter arterial embolization interrupts the arterial blood flow to small tumors by injecting small particulate embolic or chemotherapeutic agents into the artery supplying the tumor. Ischemia and necrosis of the tumor occur as a result.
For multiple small lesions, ultrasound-guided injection of al-cohol promotes dehydration of tumor cells and tumor necrosis (Habib, 2000; O’Grady et al., 2000).
Surgical resection is the treatment of choice when HCC is con-fined to one lobe of the liver and the function of the remaining liver is considered adequate for postoperative recovery. In the case of metastasis, hepatic resection can be performed when the pri-mary site can be completely excised and the metastasis is limited. Metastases to the liver, however, are rarely limited or solitary. Capitalizing on the regenerative capacity of the liver cells, some surgeons have successfully removed 90% of the liver. However, the presence of cirrhosis limits the ability of the liver to regener-ate. Staging of liver tumors aids in predicting the likelihood of surgical cure. A staging system for liver tumors is summarized in Chart 39-11.
In preparation for surgery, the patient’s nutritional, fluid, and general physical status is assessed and efforts are undertaken to ensure the best physical condition possible. Support, explanation, and encouragement are provided to help the patient prepare psy-chologically for the surgery.
Extensive diagnostic studies may be performed. Specific stud-ies may include liver scan, liver biopsy, cholangiography, selective hepatic angiography, percutaneous needle biopsy, peritoneoscopy, laparoscopy, ultrasound, CT scans, MRI, and blood tests, particu-larly determinations of serum alkaline phosphatase, AST, and GGT and its isoenzymes.
Removal of a lobe of the liver is the most commonsurgical procedure for excising a liver tumor. If it is necessary to restrict blood flow from the hepatic artery and portal vein beyond 15 minutes, it is likely that hypothermia will be used. For a right-liver lobectomy or an extended right lobectomy (including the me-dial left lobe), a thoracoabdominal incision is used. An extensive abdominal incision is made for a left lobectomy.
In cryosurgery (cryoablation), tumors are de-stroyed by liquid nitrogen at −196° C. To destroy the diseased tis-sue, two or three freeze-and-thaw cycles are administered via probes during open laparotomy. This technique has been used alone or as an adjunct to hepatic resection in HCC and colorectal metastases not amenable to radical surgical excision. The efficacy of cryosurgery is still being evaluated; indications and outcomes require further investigation.
Removing the liver and replacing it witha healthy donor organ is another way to treat liver cancer. Recur-rence of the primary liver malignancy after transplantation, how-ever, has been reported to occur in 70% to 85% of cases, and the survival time after recurrence is brief. Metastasis and recurrence may be enhanced by the immunosuppressive therapy needed to prevent rejection. The patient with small tumors may have a good prognosis after transplantation, but recurrence is common with tumors greater than 8 cm in diameter or those that are multi-focal or have vascular invasion (Bacon & Di Bisceglie, 2000). See the discussion of liver transplantation that follows.
If the patient has had surgery to treat liver cancer, potential problems related to cardiopulmonary involvement include vascu-lar complications and respiratory and liver dysfunction. Metabolic abnormalities require careful attention. A constant infusion of 10% glucose may be required in the first 48 hours to prevent a precipitous fall in the blood glucose level resulting from decreased gluconeogenesis. Because extensive blood loss may occur as well, the patient will receive infusions of blood and IV fluids. The patient requires constant, close monitoring and care for the first 2 or 3 days, similar to postsurgical abdominal and thoracic nursing care.
The patient undergoing cryosurgery is monitored closely for hypothermia, hemorrhage, or bile leak; myoglobinuria can occur as a result of tissue necrosis and is minimized by hydration, di-uresis, and at times medications (allopurinol) to bind to and aid in the excretion of toxic products.
If the patient will receive chemotherapy or radiation therapy in an effort to relieve symptoms, he or she may be discharged home while still receiving one or both of these therapies. The patient may also go home with a biliary drainage system in place. The need for teaching is great because of the need for the patient to participate in care and the family’s role in care at home.
The nurse instructs the patient torecognize and report the complications and side effects of the chemotherapy that may occur and the actions and desired and undesirable effects of the specific chemotherapy regimen. The nurse also emphasizes the importance of follow-up visits to assess the patient and the tumor’s response to chemotherapy and radi-ation therapy.
If the patient is receiving chemotherapy on an outpatient basis, the nurse explains the patient’s and family’s role in managing the chemotherapy infusion and in assessing the infusion/insertion site. The nurse encourages the patient to resume routine activi-ties as soon as possible, while cautioning him or her to avoid ac-tivities that may damage the infusion pump or site.
The family and the patient at home with a biliary drainage system in place typically fear that the catheter will be dislodged. They need reassurance and instruction to reduce their fear that the catheter will fall out easily. The patient and family also re-quire instruction on catheter care. They need to learn how to keep the catheter site clean and dry and how to assess the catheter and its insertion site. Irrigation of the catheter with sterile normal saline solution or water may be prescribed to keep the catheter patent and free of debris. The patient and caregivers are taught proper technique to avoid introducing bacteria into the biliary system or catheter during irrigation. They are instructed not to aspirate or draw back on the syringe during irrigation to prevent entry of irritating duodenal con-tents into the biliary tree or catheter. The patient and caregivers are also instructed about the signs of complications and are en-couraged to notify the nurse or physician if problems or ques-tions arise.
In many cases, referral for home care enablesthe patient with liver cancer to be at home in a familiar environ-ment with family and friends. Because of the poor prognosis as-sociated with liver cancer, the home care nurse serves a vital role in assisting the patient and family to cope with the symptoms that may occur and the prognosis. The home care nurse assesses the patient’s physical and psychological status, the adequacy of pain relief, nutritional status, and the presence of symptoms indicat-ing complications of treatment or progression of disease. During home visits, the nurse assesses the function of the chemotherapy pump, the infusion site, and the biliary drainage system, if indi-cated. The nurse collaborates with the other members of the health care team, the patient, and the family to ensure effective pain man-agement and to manage other problems that may occur: weak-ness, pruritus, inadequate dietary intake, jaundice, and symptoms associated with metastasis to other sites. The home care nurse also assists the patient and family in making decisions about hospice care and assists with initiation of referrals. The patient is encour-aged to discuss preferences for end-of-life care with family mem-bers and health care providers.
Copyright © 2018-2020 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.