AIDS-RELATED CANCERS
Several cancers are more common or more aggressive in people infected
with HIV, the virus that causes AIDS. These malignancies include certain
types of immune system cancers known as lymphomas, Kaposi's sarcoma (KS)
and anogenital cancers primarily affecting the cervix and anus. HIV or
the immune suppression it induces appears to play a role in the development
of these cancers.
Doctors diagnose the cancers common in people with AIDS by visualizing
suspected cancerous tissues with magnifying devices and removing small
samples of the tissue. The tissue samples are then examined under a microscope
for distinctive cancerous cells. Doctors also may use x-rays, computerized
tomography (CAT) scans or magnetic resonance imaging (MRI) scans of the
suspected cancerous areas to aid diagnosis.
Lymphomas
Lymphomas are cancers of the lymphatic system, which is a part of the
immune system that defends the body against disease. The lymphatic system
is made up of a network of vessels that carry lymph, a colorless fluid
that contains lymphocytes, infection-fighting white blood cells. Other
parts of the lymphatic system include the lymph nodes, which are bean-shaped
nodules located throughout the body but concentrated in the groin, neck,
underarms, and abdomen.
The types of lymphomas most commonly associated with HIV infection are
called non-Hodgkins lymphomas or B-cell lymphomas. In these types of cancers,
certain cells of the lymphatic system grow abnormally. They divide rapidly,
growing into tumors.
Lymphomas also can affect the liver, bone marrow or spleen. Swollen
lymph nodes are the most common symptom, but other symptoms can occur,
including fevers, weight loss, fatigue, abdominal pain and vomiting. People
with central nervous system lymphomas, in which the brain or spinal cord
is affected, can develop confusion, loss of memory or speech, seizures
or headache.
Treating a person with HIV-related lymphoma often proves difficult because
the immune system is already weakened by HIV, and standard chemotherapy
regimens will further suppress immune function. Doctors prescribe specific
treatment regimens depending on the stage of the disease, the type of
lymphoma the patient has, other opportunistic diseases and immune cell
levels.
Either radiation therapy or a combination of anti-cancer drugs can be
used to combat AIDS-related lymphomas. Chemotherapy can cause nausea,
vomiting, fever, diarrhea, hair loss and a loss of immune cells. To protect
the immune system, the growth factors GM-CSF or G-CSF may be prescribed
to stimulate the bone marrow to boost production of white blood cells.
Radiation generally is used to treat patients with lymphoma originating
in the central nervous system.
Kaposi's Sarcoma
KS is a disease in which cancerous cells are found in the tissues under
the skin or in mucous membranes that line the mouth, nose or eye. KS also
can spread to the lungs, liver, gastrointestinal tract and lymph nodes.
People with KS often develop raised, usually painless blotches on the
skin or inside the mouth. The blotches appear reddish-purple in light-skinned
people and bluish or brownish black in dark-skinned people. When KS occurs
in the gastrointestinal tract, it can cause bleeding; KS may result in
difficulty in breathing when it affects the lungs. KS can cause painful
swelling, especially in the legs.
The disease often is neither life-threatening nor disabling in people
with AIDS, so treatment may not be necessary. Doctors usually recommend
therapy if KS is widespread and painful or uncomfortable, or causing respiratory
symptoms or swelling. KS patients also are treated if the disease is rapidly
progressing or a cosmetic problem. If KS is not widespread, doctors can
use radiation directed at tumor sites on the skin. Doctors also can remove
lesions surgically or destroy them by freezing the tissue with liquid
nitrogen or by injecting them with anti-cancer drugs.
Patients with advanced, widespread (disseminated) or rapidly progressing
KS usually are treated with anticancer drugs used singly or in combination.
As with lymphoma treatment, growth factors may be prescribed to counter
the immune suppression induced by the chemotherapy.
Alpha interferon may be effective in treating patients with KS who have
relatively healthy immune systems, as measured by the levels of certain
immune cells in the blood and an absence of other major opportunistic
diseases.
Anogenital Cancers
Immune suppression may make people with AIDS more susceptible to cancers
of the cervix or anus that are associated with human papillomavirus infection
(HPV). Cancer of the cervix usually occurs without symptoms, although
it can cause abnormal vaginal bleeding. Anal cancer can cause red patches
on the anus.
Pap smears, in which a scraping of cells is taken from the cervix, can
detect cervical cancer at its earliest stage when treatment is highly
effective. Women who are infected with HIV should receive Pap smears every
6 to 12 months to detect abnormal cervical cells that may develop into
cancerous cells if left untreated.
Early cervical cancer is managed by burning, freezing or laser destruction
of abnormal cells or by surgical removal of affected tissue. More advanced
cervical cancer is treated by surgically removing the cervix and uterus,
and sometimes the upper vagina and lymph nodes in the area as well, or
by radiation or chemotherapy.
Doctors sometimes treat patients with anal cancers by surgically removing
the tumorous tissues. For some patients, however, radiation therapy may
be required, or it may be necessary to remove the anus and rectum.
For more information on AIDS studies, call the AIDS Clinical Trials Information
Service: 1-800-TRIALS-A.
For federally approved treatment guidelines on HIV/AIDS, call the HIV/AIDS
Treatment Information Service: 1-800-HIV-0440.
Source:
Office of Communications
National Institute of Allergy and Infectious Diseases
National Institutes of Health
Bethesda, MD 20892
Public Health Service
U.S. Department of Health and Human Services
November 1994
The content on mdchoice is intended solely for informational
purposes and is in no way intended to be used for making
decisions about your healthcare. There is no substitute
for discussing your medical and health-related needs with
your physician.
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