Monday, November 22, 2010

All About Liver Cancer

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A cancer is an uncontrolled proliferation of cells. In some the rate is fast; in others, slow; but in all cancers the cells never stop dividing. This distinguishes cancers - malign tumors or malignancies - from benign growths like moles where their cells eventually stop dividing. Cancers are clones. No matter how many trillions of cells are present in the cancer, they are all descended from a single ancestral cell. Cancers begin as a primary tumor. At some point, however, cells break away from the primary tumor and - traveling in blood and lymph - establish metastases in other locations of the body. Metastasis is what usually kills the patient.

Liver Cancer
There is no consensus regarding the optimal treatment of patients with liver tumors. This contributes to the pessimistic attitude that many have regarding the treatment of liver cancer. Aggressive treatment strategies can cure or significantly prolong the life of many patients with liver cancer.
The liver is a common site of metastases from a variety of organs such as lung, breast, colon and rectum. When liver metastases occur at the time of initial diagnosis of the primary tumor, they are described as synchronous. If detected after the initial diagnosis, they are described as metachronous. The liver is frequently involved since it receives blood from the abdominal organs via the portal vein. Malignant cells detach from the primary cancer, enter the bloodstream or lymphatic channels, travel to the liver, and grow independently. We do not understand the mechanism of how a tumor cell can leave the primary site and grow in specific organs. Potentially, the environment of the liver is suitable to the growth of certain tumor cells. Once a tumor begins to grow in the liver, it receives its blood supply from the hepatic artery.

How Liver Cancer Develops .


Cancer is an uncontrolled replication of damaged cells. This condition usually produces a mass called a tumor. Cancer is the direct result of either a mutation of the cellular DNA or some sort of damage to the cellular DNA. For the cancerous cell to actually develop into a tumor, it must be able to grow and to replicate itself. A cancerous cell that cannot grow or make a copy of itself will die or lie dormant for an extended period.

What actually causes genetic mutations or DNA damage is not yet completely understood, but several significant factors that encourage cancer development have been identified.

Carcinogenesis


Carcinogenesis is a multistage process that begins when a carcinogen causes a genetic change or damages the DNA in a normal cell. This makes the cell more vulnerable to other genetic changes. This stage is called "initiation." If the process ended here, and the cancerous cell did not grow and replicate, no cancer would form.

The next stage of carcinogenesis is called "promotion." This occurs when the initiated cell is exposed to an agent that enhances its growth into a larger mass.

When a tumor actually forms, it has all of the same basic needs as a normal cell. Because the tumor cells are genetically damaged, they are inefficient and rob normal cells of important oxygen and nutrients. In addition, a malignant tumor grows uncontrollably and can eventually interfere with the function of vital organs, such as the liver.

Growth of Cancer
A small tumor no larger than 1 millimeter in diameter can sustain itself in such a manner indefinitely. But it cannot grow any larger unless the tumor itself begins to generate a network of blood vessels to help supply additional nutrients.

A clinically detectable tumor is about 1 gram in weight and made up of at least 1 billion cells.
Metastatic tumors form when large progressive tumors shed tumor cells. These tumor cells must be able to grow and function apart from the primary tumor
metastatic - adjective used to describe cancer cells that have spread from a primary site somewhere else in the body


Detecting Cancer


Early stages of cancer can be asymptomatic and may go undetected for months or even years. When symptoms do develop, they are most pronounced as pain.

Pain associated with cancer is a result of several possibilities: invasion or destruction of normal tissue with cancer cells; stretching of internal tissue by tumor growth; pressure of tumor on an organ; blockage of a vital passageway by the tumor; and infection caused by cancer.

Other symptoms may include loss of appetite, loss of weight, fever of unknown origin, limb weakness, sensory loss, or an absence of tendon reflexes in the limb.

Liver cancer, both primary and metastatic, often exhibits symptoms of general malaise as well as pain and tenderness. The discomfort is usually of a moderate degree and most often in the upper or upper right part of the abdomen. In more advanced cases, symptoms of jaundice, a yellowing of the skin and eyes, may also appear.

Frequently, patients with liver tumors are asymptomatic (have no symptoms). The diagnosis is made during an examination as part of a routine follow-up after cancer treatment. If a patient with colon cancer is going to develop metastatic disease in the liver, this will occur most likely within two years. Occasionally patients with liver tumors will develop symptoms such as pain, abdominal fullness, fever, or jaundice.

When your primary care physician finds a reason to suspect cancer in the liver, you will be advised to undergo a series of diagnostic tests. Some of these tests are noninvasive and require a brief visit to a clinic or lab. Others are more involved and may require an overnight stay in a hospital.

When you schedule your testing, consider scheduling the more difficult tests on separate days. While it may be less convenient, some tests may tire you and require a day or so of recovery. Consider scheduling your tests on days when a friend or family member can accompany you. Not only can this person provide support, but he or she can also assist technicians and medical personnel with your health history as well as help them keep you comfortable.

When your testing is complete, don't leave the testing facility until you feel ready. Even noninvasive testing can be exhausting, so don't expect to feel energetic afterwards.

Remember that diagnostic testing can become quite stressful. Allow yourself as much time as safely possible to learn about the test and to recover from the testing experience.

Staging
In the United States, the most common form of liver tumor is metastases (i.e., the spread of a cancer from another part of the body). In 40 - 80% of patients with cancer of the colon, the tumor will eventually spread from the colon to the liver. This event may occur at any time, beginning from the time of diagnosis of the colon cancer to many years after treatment of the cancer. Other types of cancer (i.e. pancreas, stomach, breast, lung, etc.) may also spread to the liver during the course of the disease.

Primary liver cancer (or hepatocellular cancer), intrahepatic bile duct cancer (cholangiocarcinoma), are diseases that occur when the tumor originates in the liver and did not spread from another organ. In Asia and Africa, hepatocellular cancer is the most common type of malignancy and frequently develops in patients who have liver cirrhosis.
Staging is part of the diagnostic process and consists of gathering detailed information about the tumor to determine its stage of development. Staging is critical in determining if your cancer is advanced. The exact stage of your cancer will determine the treatment options. To determine the stage of your disease, your physician uses a variety of diagnostic procedures to determine the type of tumor, size and location, and whether the tumor has metastasized or spread to another region of the body.

During staging, the tumor is analyzed and classified according to a specific tumor classification system.

The most common system is called TNM.
T classifies the size of the tumor and is usually followed by a number from 1 to 4.
Classification of T1 for example, designates a relatively small tumor.
T4 represents a more advanced tumor or multiple tumors in both lobes of the liver.
TX is used to denote an inaccessible tumor (one that cannot be adequately classified because it cannot easily be observed.)
N classifies the lymph nodes.
A NO indicates no lymph node involvement with cancer.
N1 indicates that the tumor has spread to the lymph nodes.
NX means that the lymph nodes cannot be accessed.
M classifies the spread of the tumor to other organs.
MO reflects an absence of spread.
Ml means the tumor has spread to a distant organ.
MX means that the metastases are not accessible.
The success of treatment is directly related to the stage of the cancer. Patients with Stage I have a better chance of being cured of their cancer than a patient with Stage IV disease.

taging of Liver Cancer
Each type of cancer has specific staging criteria. In general the different stages can be summarized as follows:

Stage I: Localized and Resectable
resectable - surgical removal of a section of an organ is a feasible option
Tumor is found in one location of the liver and could be treated surgically.

Stage II: Localized and Possibly Resectable
Primary tumor is found in one or more locations in the liver and may be treated surgically. The decision to surgically treat the disease will depend upon the experience of the physician.

Stage III: Advanced
Cancer has spread to more than one location in the liver and/or to other parts of the body. Frequently requires multiple treatment modalities for maximum benefit. Often, surgical resection does not provide benefit to the patient.

Stage IV: Disseminated
Cancer involves multiple sites throughout the body. Frequently, surgery is not indicated and chemotherapy is the best option.
This classification system is not standardized across all types of cancer, and each type of cancer has its own interpretation. Consult your physician for an exact interpretation of the stages and the letter designators as they apply to your diagnosis.

Physical Exam
A thorough history and physical exam is an important part of your visit to an oncologist. Such factors as cancer history, race, age, and sex contribute to the final diagnosis and development of a treatment strategy. Your physical appearance will give the physician a sense of the overall health of the liver. Yellowing of the skin and/or eyes is called jaundice, a condition that occurs when there is a build up of bile in the bloodstream caused by a malfunctioning liver, bile duct or gall bladder. This may also cause dark colored urine and clay colored bowel movements.

Your liver will be examined by feeling the right upper quadrant of your abdomen. This examination is usually done while your are lying on your back and relaxed. The physician begins in the lower region moving in an upward position feeling for the overall shape and firmness of your liver. The size of your liver can be estimated by percussion (placing one finger on your rib cage and tapping it with another finger), which uses sound as a determinate. You will also be examined for the presence of ascites (fluid that accumulates in the abdomen).

Your exam will also include an assessment of your axillary (armpit) and supraclavicular (above the collarbone) lymph nodes to determine if they are enlarged, which could indicate involvement with cancer.

If you have had cancer previously, the primary site (i.e. colon, rectum, breast) of the cancer will be evaluated to determine if the disease has recurred.

Blood Tests
A series of blood test are ordered to determine your general state of health and the health of your liver. A Complete Blood Count is a standard series and includes the following tests:
Hematocrit - measures the volume of red blood cells as a percent of the total blood volume.
Hemoglobin - measures the number of grams of red blood cells in a sample of blood.
Platelet Count - measures the number of platelets and reflects your ability to clot.
White Blood Count - measures the number of white blood cells.

Additional blood tests, usually referred to as Liver Function Tests, may be used to determine the overall functional condition of your liver. Your liver must be in satisfactory functional condition to be able to tolerate treatment.

Blood is drawn for a series of blood tests and a urine sample may be collected. Other tests, like a chest x-ray, CT scan, Ultrasound, or MRI, may be scheduled for the near future. All of these results along with your overall health during your first and subsequent visits will help your physician to accurately diagnose your condition.

Other blood tests may also be ordered to determine specific information about your liver cancer. A CEA test will detect the level of carcinoembryonic antigen (CEA), or AFP test which will measure the level of alpha fetoprotein (AFP).

CEA is a protein that is normally produced in the fetus during the first two trimesters of pregnancy. It is also produced by adenocarcinomas of the digestive system (such as the colon and rectum, pancreas, stomach), lung, and breast. The highest levels of CEA are seen in patients with liver metastases from colon cancer. Serial measurements of CEA during treatment provide important information on the efficiency of treatment. After undergoing treatment for colon cancer the CEA level should return to normal. If the treatment is incomplete, the CEA will not become normal.

The most common use for CEA is to monitor patients for the early detection of recurrent or metastatic cancer. By detecting metastatic cancer early, the treatment options are greater and more successful. Unfortunately, not all patients with cancer will have elevated CEA levels. Discuss your CEA results with your physician and determine if CEA monitoring can be helpful in your care. A normal level for a non-smoker is <~3 ng/ml and 3 - 5 ng/ml for a smoker. AFP is also produced in the fetus but decreases steadily and becomes normal by 6 - 12 months of age. This substance is produced by patients with hepatocellular carcinoma or germ cell tumors. Approximately 70 - 90% of patients with hepatocellular carcinoma will have levels that range from above normal (greater than 20 ng/ml) to 10,000,000 ng/ml. A small elevation in AFP may occur in patients with non-malignant disease such as cirrhosis or viral hepatitis. Like CEA, AFP is used to monitor the effectiveness of cancer treatment in patients with hepatocellular carcinoma and germ cell tumors. Increasing levels of these markers is associated with tumor growth, but the absence of an elevation can not be interpreted as an absence of tumor.

Chest X-Ray
A chest x-ray is necessary to determine if cancer has spread to your lungs or if fluid surrounds your lungs, a condition called a pleural effusion. This test will also provide information about the general health of your lungs which is important when making treatment plans.

While chest x-rays are considered safe, overexposure to radiation is a concern. If you have had a chest x-ray recently, ask your physician if another is absolutely necessary. You may also use this opportunity to discuss additional prescribed tests that will expose you to x-rays.

CT-Scan
The CT scan (Computerized Tomography) is a form of x-ray that creates an image of the inside of the body. Unlike the chest x-ray, which is a broad x-ray beam sent over a large area, the CT-scan is a thin, pencil-like x-ray beam directed over a small part of the body. The scanner itself has an arm that directs the thin x-rays through the body as it rotates around the patient. The scanner's computer analyzes the data to build a view of the tissues and organs of the body.

Frequently, a contrast dye is injected into the vein to enhance certain regions of the liver. In addition, you may also be asked to drink a fluid that will help to examine the organs in the abdomen. Different dyes and scanning techniques will yield a wealth of information about the condition of the liver.
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Results from CT scans may reveal tumors and aid in determining the number and location. They can also detect organ disorders or abnormal structures, blocked ducts, and abnormal tissues.

CT scans are usually scheduled at a clinic on an outpatient basis. The patient lies on a table and must remain very still for the entire process. The CT scan may take as long as an hour.

Below is a CT scan of a patient with a liver tumor. The liver is located along the left half of the image and is light gray in color. The white tubular structures are the normal liver blood vessels. The liver tumor is dark and located on the edge of the liver and extends toward a blood vessel.

CT- Angiogram
The normal liver cell receives the majority of its blood supply from the portal vein and a liver tumor receives the majority of its blood supply from the hepatic arerty. Thus, dye injected into the portal vein will emphasize the normal liver cells and make the normal liver bright. In contrast, the liver tumor will be very dark. This test accurately defines the number of metastases and their relationship to liver blood vessels which is important information in planning treatment strategies.

The CT angiogram is similar to the CT scan except that it involves a contrast dye injected into one of the arteries (superior mesenteric artery) that supply the liver. The x-rays detect the dye as it flows through the bloodstream, outlining the blood vessels in the liver and the flow of blood through the organ. Computer analysis generates images and stores them for further study.

Unlike CT scans, most CT angiograms are done in a hospital setting. A local anesthetic is administered before a catheter is inserted into a blood vessel in your groin and the tip of the catheter is placed in proper position near your liver and an injection of contrast is made. Shortly after this injection, a CT scan is performed. This test provides very detailed information on the information on the number and location of your liver tumors. Typically, the test takes 2 -3 hours to perform and you must stay in the hospital for 6 - 8 hours to be observed for potential complications.

Ultrasound
Ultrasound uses sound waves, not x-rays, to generate images. A jelly-like substance is applied to the skin overlying your liver. Then a probe, called a transducer, is passed over the skin. The transducer sends out sound waves that pass through the body and are echoed back. The transducer receives the echoes and transmits them to a computer console which in turn interprets the echo data as internal organs and tissues.

Because ultrasound is simple, inexpensive and noninvasive, it is often one of the first tests ordered during the staging process. Unfortunately, test results are highly dependent upon the sonographer, the quality of the scanner, and the overall build of the patient. As a result, ultrasound may not detect all tumors in all cases.

Ultrasound may be performed in the physician's office or on an outpatient basis in a clinic. Most ultrasound tests take only a few minutes and results are obtained immediately. In patients with liver tumors, ultrasound is used to locate and measure the size of a tumor and to determine if it is solid or cystic.

In addition, ultrasound is an important modality that is used at the time of surgery and is called intraoperative ultrasound. This examination should be performed on all patients who undergo a surgical procedure on the liver. It will identify all of the tumors within the liver and clarify the relationship to blood vessels in the liver. The probe is placed directly on the liver at the time of surgery. This test provides critical information that will influence the treatment strategy.

All liver surgeons should be experienced in performing intraoperative ultrasound. Below is an intraoperative ultrasound image of a liver tumor. The edges of the tumor are indicated by the arrows. No other tumors are present in the liver
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MRI
Magnetic Resonance Imaging (MRI) is the most advanced imaging technology available today. MRI is generally considered safer than other imaging techniques because it is noninvasive and because it does not employ x-rays. MRI uses radio waves and a powerful magnet to create images of internal organs and tissue. This test is frequently used when findings on a CT scan are not clear.
During the imaging process, the magnet excites the hydrogen atoms in the body's cells. In turn, these hydrogen atoms give off tiny electrical charges that are picked up by a scanner and assembled into images. It takes a series of images to build a picture of the isolated area. MRI is particularly sensitive to liver tissue and is capable of displaying liver vasculature without the need of a dye. The following images are from a patient with colorectal liver metastases. The first is a CT scan that suggests a subtle abnormality (indicated by arrow). The second image is an MRI scan which shows three separate areas (indicated by arrows) of liver metastases
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.Colonoscopy and Laparoscopy
Colonoscopy may be ordered if there is reason to suspect primary colorectal cancer or if you have had colon cancer in the past. A colonoscope is a highly flexible instrument used to examine the entire length of the colon. The instrument is a tiny viewing camera that gives off light and allows the physician to see inside the patient's colon. Occasionally, during colonoscopy, a small tissue sample will be obtained for laboratory analysis (called a biopsy).

Laparoscopy is similar to colonoscopy except that it uses an instrument called a laparoscope. Unlike colonoscopy, most patients undergoing laparoscopy will require a general anesthetic. Like the colonoscope, it is a viewing camera that also emits light. The laparoscope is a small tube-like device used primarily for examining the liver and pancreas. For this test, a small cut is made in the abdomen to insert the instrument. The surgeon may use this opportunity to perform a biopsy.

Liver Biopsy
Often times a liver biopsy will be ordered because it provides reliable information for a cancer diagnosis. A biopsy involves the collection of a small tissue sample that is then examined under a microscope. Normal cells have a distinct and orderly appearance and are different than cancer cells which are chaotic and malformed. By examining the cells under a microscope, the pathologist can determine the presence of diseased cells and the extent of their invasion.

The first image shows a normal liver. The white arrows show the liver sinusoids (small blood vessels that supply liver cells). The dark arrow shows the portal pedicle which contains 3 structures (liver artery, vein and bile duct). Blood enters the liver from the portal pedicle, passes through the liver sinusoids and leaves the liver through a central vein.

The next image shows a cirrhotic liver. The arrows outline a nodule within the liver. Comparing this image to the previous one shows scar and fatty deposits (as indicated by the clear white spots).


The last image shows a metastatic colon cancer in the liver. The arrows show the area of the tumor, which is surrounded by scar tissue.


Biopsy procedures are usually performed as an outpatient. A local anesthetic is administered before a thin needle is inserted into the tumor and a sample of tissue is removed. Biopsies may be assisted by ultrasound or CT scans or may be performed using a laparoscope.

Surgery 
Every patient with a liver tumor should be evaluated for a resection. It is the only chance for cure. Removing the tumor will rid the body of the cancer and also prevent further spread to other regions. Unfortunately, not all patients are eligible for a liver resection.

The liver is a privileged organ in that it has the ability to regenerate if part of it is removed and this allows surgeons to operate upon it successfully. In patients with colon cancer that has spread to the liver, liver resection can cure 25 - 45% of the patients. The operative mortality is less than 2%. To achieve these outcomes requires (1) appropriate selection of surgical candidates and (2) an experienced surgical team (surgeon, anesthesiologist, intensive care staff, etc.) that performs liver operations frequently. Only those patients who are likely to benefit from resection should undergo a surgical procedure.

Patients may also develop metastatic colorectal cancer to both the lungs and liver. In select patients, simultaneous resection of metastases from the lung and liver can provide significant benefit.

Other indications for liver resection are metastases from other sites such as breast, kidney, lung, selected tumors of the pancreas and small intestine and sarcomas. Although these diagnoses are controversial indications, 2 year survival rates of 90% have been obtained. This improved survival occurs in patients who respond to chemotherapy and have disease only in the liver. Other indications for resection are tumors that originated in the liver, called hepatocellular cancer and cholangiocarcinoma.

To be considered for a liver resection, the cancer must be confined only to the liver so that removal will eliminate all disease from the body. Removing a tumor from the liver and leaving other areas in the body with cancer will not be curative. An exception is a patient with a metastatic carcinoid tumor as they can benefit (i.e., improvement in symptoms) from removal of greater than 90% of the liver tumor.

A liver surgeon will devote a significant amount of time to make sure that the appropriate patient is selected for surgery. Routine tests may include a CT scan of the abdomen, pelvis, chest, colonoscopy (if the patient has had a colon cancer). Other important information necessary to make a decision is the number, size, and location of the liver tumors. Only when the surgeon has determined that the cancer is limited to the liver will a recommendation be given to proceed with surgery. To be effective, all tumors must be removed with a margin of 1/2 inch of normal liver in order to remove microscopic cancer cells that may surround the obvious tumor.
A variety of liver resections can be performed. The options range from resection of a lobe (left or right) to segments (or small portions) of the liver. Resection of segments of the liver (called segmentectomy) permit a surgeon to effectively treat multiple liver tumors. My preference is to resect segments whenever possible in order to preserve normal liver and also to treat more tumors. If it is technically feasible, I will resect up to six tumors. In this group of patients I will usually insert an hepatic intra-arterial catheter for post-operative chemotherapy. Clearly, this is an aggressive and controversial approach but it can be effective and potentially curative.
A liver resection can take 2 - 5 hours to perform. In the majority of patients, a liver resection does not require a blood transfusion. The patient will be able to drink fluids on the first post-operative day and often is discharged in 4 - 6 days.

A CT scan from a patient with hepatic metastases from colon cancer is shown here. The tumor isdelineated by the dark area and shown by the arrow. This is in marked contrast to the normal gray color of the liver
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This patient underwent resection of a segment of the liver and the next two images show the specimen with a 1 cm. margin.
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The last photograph shows the liver after the tumor has been removed. The patient recovered uneventfully from the surgery
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Unfortunately, the majority of patients with liver tumors are not candidates for resection. Tumors located near important liver blood vessels may be unresectable since certain blood vessels cannot be removed. If the patient has multiple tumors, the surgeon may not be able to completely remove all of them. In this situation, the patients may be candidates for other types of therapy. One effective modality is cryosurgery.

Cryosurgery
Cryosurgery is a new technique that can destroy tumors in a variety of sites (brain, breast, kidney, prostate, liver). Cryosurgery is the destruction of abnormal tissue using sub-zero temperatures. The tumor is not removed and the destroyed cancer is left to be reabsorbed by the body. Initial results in properly selected patients with unresectable liver tumors are equivalent to those of resection.

Cryosurgery involves the placement of a stainless steel probe into the center of the tumor. Liquid nitrogen is circulated through the end of this device. A picture of the cryoprobe is shown.
The tumor and a half inch margin of normal liver are frozen to -190°C for 15 minutes, which is lethal to all tissues. The area is thawed for 10 minutes and then re-frozen to -190°C for another 15 minutes. After the tumor has thawed, the probe is removed, bleeding is controlled, and the procedure is complete. The patient will spend the first post-operative night in the intensive care unit and typically is discharged in 3 - 5 days.

Proper selection of patients and attention to detail in performing the cryosurgical procedure are mandatory in order to achieve good results and outcomes. Frequently, cryosurgery is used in conjunction with liver resection as some of the tumors are removed while others are treated with cryosurgery. Patients may also have insertion of a hepatic intra-arterial artery catheter for post-operative chemotherapy. As with liver resection, your surgeon should have experience with cryosurgical techniques in order to provide the best treatment possible.
Below is a picture of an iceball in a patient with a metastases from a colon cancer
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Following resection or cryosurgery, your physician may recommend chemotherapy. In my experience, patients who respond to chemotherapy and undergo surgical treatment of their liver tumors will achieve superior outcomes. Discuss the use of chemotherapy with your physician to determine if this will be of benefit for you in the treatment of your disease.

Your choice of surgeon is a critical part of your treatment plan. Choose a surgeon who is Board Certified and who has performed the specific operation many times. Choose a surgeon who is willing to answer your questions and provide as much information as you need. Your surgeon should be confident and able to reassure you that everything possible is being done to improve your condition.

Chemotherapy
Chemotherapy uses drugs to treat the cancer. These drugs work by interfering with the growth of cancer cells and lends to cell death. Chemotherapy can be administered in a variety of ways. Treatment of the entire body is called systemic chemotherapy, while treatment of localized areas is called regional chemotherapy. If more than one anti-cancer drug is administered at once, the treatment is called combination chemotherapy. Oftentimes, chemotherapy will be used in conjunction with other treatments like radiation and surgery and is termed adjuvant chemotherapy.

Chemotherapy is administered in a variety of ways: orally, intravenously or intra-arterially. Most oral drugs can be administered at home or in the doctor's office. Intravenous drugs are usually administered at a clinic or in the doctor's office. In some cases, drugs will be administered intra-arterially with the use of a sophisticated pump. The actual treatment will depend on the type of cancer, the level of cancer invasion, and the extent of the disease. A drug may be taken every day, every week, or every month. A drug may be taken in cycles alternated with a rest period when no drug is taken.

Effectiveness of treatment is evaluated regularly with physical exams, blood tests and x-rays. A drug is considered effective if it causes the cancer cells to shrink, to stop growing, or to die.
Because anti-cancer drugs attempt to kill cancer cells, many of them will also attack and kill healthy cells. Side effects are a direct result of the killing of healthy cells. Certain cells are more susceptible to damage than others, including bone marrow cells, cells in the digestive tract, reproductive system and hair follicles. Although many patients never experience symptoms, possible side effects include nausea and vomiting, hair loss, fatigue, increased chance of bleeding and/or getting an infection, and anemia. Most of these side effects will disappear in a few days or weeks after chemotherapy ends.

Metastatic colon cancer to the liver can be treated with chemotherapy in a variety of ways. One of the most common regimens is the systemic or intravenous administration of 5 - Fluorouracil (5 FU) and Leucovorin. This drug combination is given in the vein as an outpatient and is effective in killing metastatic cancer in 20 - 30% of patients and can potentially prolong life for approximately twelve months. Other systemic drug regimens include continuous infusion of 5 FU, Tomudex, Mitomycin C, CPT-1 1 and other experimental drugs. In addition, active research protocols are investigating the effectiveness of administering chemotherapy by mouth with the goal of making the treatment easier for the patient.

Chemotherapy can also be administered directly into the liver artery and is called intra-arterial chemotherapy.

Liver tumors derive their blood supply from the hepatic artery, and intra-arterial administration will expose the tumor to very high doses of chemotherapy (100 - 400 times higher values than systemic infusion).This increased drug exposure achieves tumor shrinkage in 50 - 70% of patients. The two most commonly used drugs are 5 FU and FUDR. Administering combinations of drugs can improve the chance of tumor shrinkage.
In the majority of cases, intra-arterial chemotherapy is given through an implanted pump that will deliver drugs at a rate of 2 -3 cc/day and does not require a battery.
Drugs are loaded into the pump with a needle placed in the middle of the device.
Intra-arterial chemotherapy is given as an outpatient and once the chemotherapy has been placed into the pump (which takes 15 minutes), the patient returns to their normal activity.

Before consenting to chemotherapy, be sure to find out what drugs will be used and how they will be administered. Ask for a frank discussion of possible side effects and pay particular attention to these that may persist or cause permanent damage. Ask for alternatives and discuss what may happen if you choose not to undergo chemotherapy. Chemotherapy, like all cancer treatments, is a matter of choice and is something you should consider carefully. You should feel confident that chemotherapy is the best treatment option at the given time and that your doctor is doing everything possible to keep you informed and comfortable.

Radiation Therapy
Radiation therapy plays a relatively minor role in the treatment of liver cancer. Most primary tumors that metastasize to the liver are resistant to radiation therapy, while the healthy liver is highly susceptible to radiation damage. Radiation therapy is often used to treat patients who have tumors of the bile duct or gallbladder.

Most radiation therapy for liver cancer is used in conjunction with other forms of treatment like surgery. Sometimes radiation therapy will be administered at the time of surgery and is called Intraoperative Radiation. Radiation may also be used as palliative treatment to shrink tumors and relieve pain.

Radiation is the process of transmitting energy in the form of waves or particles. Radiation therapy uses radiation in large doses to kill cancer cells and to keep them from growing and spreading.

A special doctor called a Radiation Oncologist determines the type of treatment you will receive and supervises the treatment process. A Radiation Physicist will adjust the machine for the correct dosage of radiation to be delivered to the patient.
There are two types of radiation therapy: external or internal.

External radiation therapy involves the use of a machine called a linear accelerator that directs x-rays at cancer cells. This type of treatment is usually administered 5 days a week for 2 - 7 weeks depending upon the type of cancer and location. Because external radiation requires directing x-rays at very specific parts of the body, the actual treatment process begins by identifying the optimal areas to treat. This is done with several diagnostic tests like x-rays and CT scans.

Once the areas are identified, the Radiation Oncologist marks the exact places with permanent ink. These marks will remain on your body throughout the treatment period and are critical in delivering proper treatment. The x-rays must be directed at the same area from session to session for the treatment to be effective.

Internal Radiation Therapy, also called Brachytherapy, uses radioactive materials that are implanted in your body, usually directly into the cancer sites. Such substances as radium, cesium, iridium, iodine, phosphorus, and palladium are placed in or near the tumor.
Unlike external radiation therapy, internal radiation therapy does make your body radioactive. While the implants are in place, they give off radioactive waves that can potentially affect other people around you. Understand the goals and risks of this therapy prior to beginning this treatment.

Radiofrequency Ablation
This is a new technique that destroys liver tumors by heating them to high temperatures (80 - 100 °C).Tumors up to 4 centimeters (approximately 2 inches) in diameter can be effectively destroyed with this technique.

The patient undergoing radiofrequency ablation receives IV sedation and grounding pads are placed on the legs. A thin needle is inserted into the tumor and electrical current is passed through the tip of the needle which becomes very hot and destroys the tumor. The procedure lasts 10 - 15 minutes and the patient goes home on the same day.The majority of patients do not experience side effects and resume normal activity the following day.

Initial clinical research has shown radiofrequency ablation to be effective in controlling tumor growth in the liver.
In Italy, 29 patients with 44 liver metastases were treated with radiofrequency ablation. No complications occurredand complete necrosis occurred in 66% of patients. Eighty-nine percent of the patients survived 18 months. The ability of radiofrequency ablation to significantly prolong life in patients with liver tumors is currently under investigation.

Interstitial Laser Photocoagulation
This technique involves the insertion of a thin optical fiber into the center of the liver tumor and a laser light is emitted from the tip. The exposed cells will then undergo thermal necrosis. Since clinical experience with this technique are few, more studies are required before this treatment can be recommended.

Isolated Liver Perfusion
This treatment for liver tumors was first described over thirty years ago but has had limited clinical use. The basis of this treatment is to expose the liver to high doses of chemotherapy in order to achieve maximal tumor shrinkage. The blood supply to the liver is completely isolated from the systemic circulation so that the body is not exposed to the high dose of drugs. It requires a lengthy operation to completely mobilize the liver and to insert catheters into the hepatic artery, portal vein and hepatic veins.

Recently, initial results using different drugs have been encouraging and work continues with this modality. This is experimental therapy and should only be used in a clinical trial.

Liver Transplantation
This treatment can not be recommended for patients with hepatic metastases. This aggressive treatment will not cure patients as the majority will have early recurrence of the tumor. However, liver transplantation has been shown to be effective treatment in patients with small hepatocellular cancers and other rare tumors (i.e., epitheloid hemangioendothioloma, neuroendocrine carcinoma).
How can hepatocellular carcinoma (HCC), often caused by hepatitis B and C, be prevented? This report outlines new data on the disease, and ways that it can be prevented through vaccines and education.Morbidity & Mortality Weekly Report, July 2010
Liver disease is an important cause of morbidity and mortality in the United States, affecting persons of all ages, but most frequently individuals in the productive years of life, between the ages of 40 and 60 years. Liver disease also disproportionately affects minority individuals and the economically disadvantaged. Medical research on liver disease is critically important and further progress in research promises to bring under control the major toll of liver disease on human health and well-being. Indeed, the last 25 years of medical research in liver disease has resulted in major improvements in the survival and quality-of-life of patients with liver disease. The next 25 years should bring even more profound and important changes.To address the burden of liver diseases in the United States, the National Institutes of Health has developed an Action Plan for Liver Disease Research.
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Also On This Blog: 2010

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