Immunotherapy
Immunotherapy reinforces your body’s power to protect itself.
The immune system is your body’s
complex defensive network, with over
20 trillion cells, proteins, and other
substances to fight disease. They are on
the lookout for bacteria, viruses, and
other invaders — including cancer.
However, because cancer cells are
damaged cells created by your body
and not a foreign invader such as a
virus, your immune system doesn’t
always recognize them as hostile.
Immunotherapy — also called biological
therapy or biological response modifier
therapy — is a relatively new form
of cancer treatment that stimulates
your immune system to detect cancer
cells and fight them more effectively.

Sending in reinforcements
Doctors often administer immunotherapy
intravenously at hospitals or
clinics, but in some cases you may
be able to take shots or pills at home.
Treatment schedules vary significantly
depending on the type of treatment.
Here are some widely used therapies:
Monoclonal antibodies: Some
cancer cells are characterized by
specific antigens — or proteins
that appear on the cell’s surface. For
this treatment, scientists create monoclonal
antibodies specifically targeted
at the cancer antigen. When they’re
injected, the antibodies attach to the
antigens and destroy the cancer cells
or limit their reproduction.
You may receive the antibodies
alone, or as carriers of other therapeutic
substances. For instance,
chemotherapy agents may be attached
to monoclonal antibodies. This technique
may help make chemotherapy
more effective and reduce its side
effects. The FDA has approved several
monoclonal antibodies for use in
cancer treatment.
Interferons: When your immune
system is activated, your white
blood cells manufacture interferons.
Scientists can also create
interferons in the lab to boost your
immune response to cancer and
prevent the growth of new cancerous
cells. Interferons may also make other
treatments more effective. The FDA
has approved the use of interferon
alpha for the treatment of certain
cancers, including some blood
cancers, melanoma, and AIDS-related
Kaposi’s sarcoma.
Interleukins: These proteins,
which occur naturally in the
body and can be recreated in a lab,
promote the growth of cancer-destroying
cells and stimulate your
white blood cells to fight cancer more
actively. Interleukins are widely used
as a therapy for melanoma and
kidney cancer.
Colony-stimulating factors: These
substances, also called hematopoietic
growth factors, stimulate
the growth of new immune cells. Your
doctor may recommend them after
chemotherapy or a stem cell transplant
to help stimulate the creation of blood
cells, reducing your risk for infections,
anemia, or excessive bleeding.
Your defense network
Mounting evidence suggests that
people may become especially susceptible
to cancer when the immune
system is not working as well as it
should. What’s more, conventional
cancer treatments such as chemotherapy
and radiation sometimes
weaken your immune system in the
process of attacking tumor cells.
During biological therapy, doctors
manipulate the cells of your immune
system to invigorate its cancer-fighting
abilities, or to help it rebound
from some of the debilitating effects
of other conventional treatment.
Immunotherapy can play various
roles in the fight against cancer,
including:
- Stopping or limiting the processes
that allow cancer cells to grow
- Inhibiting the transformation of
normal or precancerous cells
into cancer
- Making cancer cells easier for your
immune system to recognize
- Turning the cells in
your immune system
into more efficient
cancer-fighters
- Changing the way cancer
cells grow to make them
act more like normal cells
- Stopping cancer cells
from spreading to other
parts of your body
- Increasing your body’s capacity
to fix the damage to healthy cells
caused by other cancer treatments