There are many different types of cancer associated with the liver, only specific
types may respond to surgery and/or chemotherapy.
The goal of this section is to present the concept of "regional chemotherapy"
for patients that have developed spread to the liver of colon or rectal cancer;
"regional chemotherapy" is almost entirely synonymous with the use of a device
called a "hepatic artery infusion pump", (abbreviated as HAIP).
But before we embark on a technical discussion of surgical and chemotherapy treatments,
it is important for you to have some basic information. Secondary vs. Primary Liver Tumors
It is important to understand the difference between cancer that arises directly
from liver cells (primary) and cancer that has spread (metastasized) to the liver
from another site (secondary). The treatment options are different for a primary
liver malignancy compared to one that has originated elsewhere and spread to the
liver. In the United States, the vast majority of patients that have a malignancy
in the liver have a secondary or metastatic cancer. Metastatic cancer began in
another organ and spread to the liver. Even if the original tumor was completely
removed, there is a risk based on having that initial tumor, for the cancer to
spread to other organs. Colorectal cancer includes cancer of the colon (the large
intestine) and rectum (the last part of the large intestine) and is a common cause
of liver metastases in the Western world.
Colorectal Cancer
Colorectal cancer is one of the most common types of cancer spreading to the liver
in the United States. Approximately 140-160,000 people will develop colorectal
cancer and approximately 60-80% of them (84,000 to 128,0000) will develop metastatic
disease (spread to other parts of the body). An operation to remove a colon cancer
will also remove several lymph nodes. Lymph nodes are located throughout the body,
and serve as local filters. Removing the lymph nodes is important because the
local lymph nodes are the most common initial site for cancer to spread. If the
lymph nodes that are removed contain cancer, then that patient has a higher risk
to develop metastasis to other organs than a patient who does not have cancer
in the resected lymph nodes.
Patients that have lymph node cancer metastases will usually be treated with systemic
chemotherapy. This type of chemotherapy is administered through your veins ("systemic"),
and is designed to destroy any microscopic remnants of tumor that may be within
remaining lymph nodes, the blood or other organs after the initial tumor has been
removed.
During and after completing a course of chemotherapy, which may be as short as
3-months or as long as year, depending on what your doctor recommends for you,
you will begin the surveillance segment of your care.
Surveillance is necessary to identify the potential return of cancer, so that
appropriate treatment(s) may be given. In general, surveillance for colorectal
cancer patients involves having a CT scan once or twice a year, having your blood
drawn every three months and colonoscopy or other means of examining the remaining
large intestine.
The CT scan will enable your doctor to see if there is any tumor spread to the
liver or within the inside of the abdomen. The blood that is drawn will be tested
for "CEA" (carcino-embryonic antigen), a marker expressed by about 80% of colorectal
cancers. If the CEA level begins to rise, then this may be an early warning sign
for your doctor that there may be returning or spreading cancer somewhere in the
body. A colonoscopy or examination of your remaining colon may be indicated to
make sure that there isn't recurrence of the cancer in the intestine or at a new
site. There is no "best" set of tests, however, surveillance will likely include
some combination of the tests discussed above.
Hepatocellular Cancer
Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide,
with approximately one million cases per year causing 250,000 deaths. Hepatocellular
carcinoma is very common in Southeast Asia, Japan, and Africa, where it accounts
for nearly 40% of all cancer. Although HCC comprises only 2-3% of cancers in the
United States, this number is growing rapidly. Increased frequency of HCC in the
United States is thought to be the result of the immigration of large numbers
of people with chronic active hepatitis B and C as well as the increasing incidence
of hepatitis C within the United States. At present, there are nearly four million
people in the United States infected with hepatitis C, and 30,000 new cases are
diagnosed per year.
In 1986, the National Institute of Health convened a consensus conference on HCC
and concluded that "partial or total hepatectomy offers the only chance for long
term disease-free survival." Unfortunately, only 10% of all patients with HCC
are candidates to undergo surgical resection at the time of diagnosis.
