|
Certain types of cancer occur so often in people with AIDS
that they are considered AIDS-defining
conditions -- that is, their presence in a person infected
with HIV is a clear sign that full-blown AIDS has developed. They are
also called AIDS-related cancers and include the following:
- Kaposi sarcoma
- lymphoma (especially non-Hodgkin lymphoma and primary
central nervous system lymphoma)
- invasive cervical cancer
Other types of cancer that may be more likely to develop in
people with HIV infection are invasive anal cancer, Hodgkin disease,
lung cancer, cancer of the mouth, cancer of the testicles, and skin
cancers, including basal cell, squamous cell, and even malignant
melanomas. Of course, people without HIV or AIDS can also have all of
these types of cancer, even the ones that are better known as
AIDS-related. They are only called AIDS-related cancers if they develop
in people with HIV infection.
In developed countries like the United States, about 4 people
in 10 with AIDS develop cancer at some time during their illness. But
the cancer picture in HIV is changing. Kaposi sarcoma and non-Hodgkin
lymphoma have decreased as anti-HIV treatment has become more common.
It seems that highly active anti-HIV therapy is one of the reasons for
the decrease in some types of cancer among those with HIV. Many other
types of cancer do not seem to be slowed by HIV treatment, and have the
same risk factors as those in people without HIV. For instance, people
who smoke and have HIV are more likely to have cancers of the lip,
mouth, throat, and lung than people who have HIV and don't smoke.
The relationship between HIV and these other cancers is still
not fully understood. However, it is believed cancers can grow quickly
because people with HIV have weaker immune systems than those without
HIV. Weaker immune systems also make cancers harder to treat. Another
factor is the lower white blood cell count that can result from HIV
infection. For instance, AIDS can make it hard for a person to take
chemotherapy because the bone marrow (which is needed to make new blood
cells) is often already damaged by the HIV infection. People with bone
marrow damage often can't take full doses of chemotherapy without
serious harm.
For those who get cancer, anti-HIV drugs have led to better
survival with anti-cancer treatment. Anti-HIV drugs also allow many
people with cancer to get full doses of chemotherapy and other standard
cancer treatment.
AIDS-related Kaposi sarcoma
Kaposi sarcoma (KS) was once an uncommon disease that mainly
affected older men of Mediterranean or Jewish ancestry, organ
transplant patients, or young men in Africa. This form is called classic KS or endemic KS.
However, in the 1970s and 80s the number of people with KS increased
dramatically.
In the past 25 years, most KS cases in the United States have
been linked to HIV infection in men who have sex with men. These cases
are called epidemic KS.
It is now known that KS in people with HIV is related to a second viral
infection. This virus is called human
herpes virus 8 (HHV-8), also known as Kaposi sarcoma-associated herpes
virus (KSHV). HHV-8 does not appear to cause disease in
most healthy people. Infection with the HHV-8 is common in the United
States among men who have sex with men, but it can also be shared
through sex between men and women. The virus is found in saliva, which
may be one of the ways it is passed to others.
In most cases, epidemic KS causes dark purplish or brownish
spots (called lesions)
that can show up at a number of places on the body. The spots may arise
on the skin or in the mouth. KS may also affect the lymph nodes and
other organs, such as the digestive tract, lung, liver, and spleen.
When they are first diagnosed, some people with HIV and KS
have no other symptoms, especially if their only lesions are on the
skin. But many -- even those with no skin lesions -- have swollen lymph
nodes, unexplained fever, or weight loss. Over time, epidemic KS
spreads throughout the body. If KS involves a lot of the lung or
intestine, it can be fatal.
In general, people who are diagnosed with epidemic KS are
started on anti-HIV drugs, and often get treatment directed at the
cancer itself. For more information about KS and its treatment, please
see our document, Kaposi Sarcoma.
Lymphomas
Non-Hodgkin lymphoma (NHL) occurs in about 4% to 10% of people
with AIDS. It is a cancer that starts in lymphoid tissue and may spread
to other organs. The number of HIV-infected people who develop lymphoma
has declined since anti-HIV drugs have been in common use.
The non-Hodgkin lymphomas that can happen in people with AIDS
are often primary
central nervous system (CNS) lymphomas. Primary CNS
lymphoma starts in the brain or spinal cord. Symptoms of CNS lymphoma
can include seizures, facial paralysis, confusion, memory loss, and
lethargy (tiredness). AIDS-related NHL can also include certain types
of intermediate and high-grade lymphomas, including Burkitt lymphoma.
The outcome for patients with AIDS-related NHL depends partly
on the type of lymphoma and partly on the person's immune function.
People with advanced NHL, a helper T-cell count less than 200, and/or
who don't get anti-HIV drugs don't usually do as well as people without
these factors.
It seems the best treatment for AIDS-related NHL is getting
more and more like treatment of NHL in those without HIV infection. At
one time, treatment was made up of low doses of chemotherapy. But while
taking anti-HIV drugs, many patients can be treated with standard
chemotherapy doses.
For patients with primary CNS lymphoma, chemotherapy or
whole-brain radiation may be used. Anti-HIV drugs are used to improve
immune function and prolong survival.
For more information on HIV/AIDS-associated NHL and its
treatment, please see our document, Non-Hodgkin Lymphoma.
Pre-cancerous cervical changes and invasive
cervical cancer
HIV-infected women are at high risk for getting cervical
intraepithelial neoplasia (CIN). CIN is the growth of abnormal,
pre-cancerous cells in the cervix, the lower part of the uterus (womb).
Over time, CIN can progress to invasive cervical cancer, in which the
cancer cells grow into deeper layers of the cervix.
CIN must be treated to keep it from progressing to invasive
cancer. This is done by removing or destroying the outer layers of
cervical cells. Studies have shown that untreated CIN is more likely to
progress to invasive cancer in HIV-infected women than in women who
don't have HIV. The standard treatments for CIN do not work as well in
HIV-infected women as they do in women without HIV. The chance of the
disease coming back after treatment is high, and seems related to the
woman's immune function. Women with T helper cell counts less than 50
are at higher risk for CIN coming back.
HIV-infected women with invasive cervical cancer and a good
immune function tend to do well with surgery and the same treatments
that women without HIV get. Those who have more advanced disease
respond poorly to radiation therapy alone. In women with advanced or
recurrent disease, chemotherapy has been used, though the woman must be
watched closely after treatment to be sure the cancer doesn't come
back. During cancer treatment, the woman's immune status must be
watched and her HIV infection treated. Anti-HIV drugs are usually given
to improve the treatment outcome for HIV-infected women with invasive
cervical cancer, no matter what her T helper cell counts are.
Women with cervical cancer tend to fare better if they do not
have AIDS. Women with T helper cell counts higher than 500 have better
outcomes. For more detailed information on cervical cancer and its
treatment, please see our document, Cervical Cancer.
Non-AIDS -related cancers
With more widespread use of anti-HIV drug treatment,
AIDS-related cancers are being seen less often. But as people with HIV
are living longer, they are developing cancers that are not generally
linked to HIV, such as lung, throat, liver, intestinal, and anal
cancers as well as Hodgkin disease and multiple myeloma. Most of the
time, treatment includes anti-HIV drugs along with standard cancer
treatments. At the same time, any other needed treatments for HIV (such
as antibiotics to prevent infections) are used.
Last Medical Review: 09/10/2009 Last Revised: 09/10/2009
|