What Are Clinical Trials
by Eleanor Nealon
Office of Cancer
National Cancer Institute
U.S. Department of Health and
General Information . . .
What Is a Clinical Trial?
Clinical Trials Important?
Why Would a
Patient Be Interested in a Clinical Trial?
Are There Risks or
Side Effects in Clinical Trials?
Why Does Cancer
Treatment Have Side Effects?
If You Are Thinking of Entering A Clinical
Trial . . .
Are You Eligible for a
What Trials Are
Available for Your Type of Cancer?
What Is Best for You?
What Are Important
Questions to Ask About a Clinical Trial?
What Is Informed Consent?
What Is It Like to Be
a Patient in a Clinical Trial?
Can You Leave a Trial at
What Protection Do You
Have as a Patient in a Clinical Trial?
What Can Help You Learn If a Trial Is Sound and Well
What Kinds of Clinical
Trials Are There?
How Are Trials Divided
How Are Clinical Trials
The National Cancer
Program and Clinical Trials
Research studies conducted with patients are
called clinical trials. As a cancer patient, you may take part in a clinical trial. This
booklet is written for you, your family and friends, to explain what clinical trials are
and to help you make a decision about entering a trial.
The time when cancer is diagnosed or when
treatment decisions are being made is very difficult. It is often hard to understand or
remember complex medical explanations. The information in this booklet is meant to
supplement what your doctors tell you. It provides answers to questions asked most often
about clinical trials. (You may not want to read the whole book at one time. It is broken
down into questions and answers that you can read now or later . )
There is a page labeled "Notes"
near the back. You may wish to write down questions to ask your doctor or nurse. Also,
there is a glossary of words that relate to clinical trials and cancer care. This is a
quick way to look up terms that you may hear or read. More information on many cancer-
related topics is available at no cost in other publications from the National Cancer
Institute (see back cover).
We hope this booklet will help to explain
how clinical studies are designed and carried out. Of course, there are good treatments
and good care for cancer patients if they take part in clinical trials or if they receive
standard treatments. You may decide not to take part in a trial, and you can still receive
good medical care. The decision to enter a clinical trial or not is always up to you.
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In cancer research, a clinical trial is a
study conducted with cancer patients, usually to evaluate a new treatment. Each study is
designed to answer scientific questions and to find new and better ways to help cancer
The search for good cancer treatments begins
with basic research in laboratory and animal studies. The best results of that research
are tried in patient studies, hopefully leading to findings that may help many people.
Before a new treatment is tried with
patients, it is carefully studied in the laboratory. This research points out the new
methods most likely to succeed, and, as much as possible, shows how to use them safely and
effectively. But this early research cannot predict exactly how a new treatment will work
with patients. With any new treatment there may be risks as well as possible benefits.
There may also be some risks that are not yet known. Clinical trials help us find out if a
promising new treatment is safe and effective for patients. During a trial, more and more
information is gained about a new treatment, its risks, and how well it may or may not
Standard treatments, the ones now being
used, are often the base for building new, hopefully better treatments. Many new
treatments are designed on the basis of what has worked in the past, in efforts to improve
Only patients who wish to, take part in a
clinical trial. You may be interested in or asked to enter a trial. Learn as much as you
can about the trial, before you make up your mind.
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Advances in medicine and science are the
results of new ideas and approaches developed through research. New cancer treatments must
prove to be safe and effective in scientific studies with a certain number of patients
before they can be made widely available.
Through clinical trials, researchers learn
which approaches are more effective than others. This is the best way to test a new
treatment. A number of standard treatments were first shown to be effective in clinical
trials. These trials help us find new and better treatments.
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Patients take part in clinical trials for
many reasons. Usually, they hope for benefits for themselves. They may hope for a cure of
disease, a longer time to live, a way to feel better. Often they want to contribute to a
research effort that may help others.
Based on what researchers learn from
laboratory studies, and sometimes earlier clinical studies and standard treatments as
well, they design a trial to see if a new treatment will improve on current treatments.
The hope is that it will. Often researchers use standard treatments as the building blocks
to try to design better treatments .
Many trials have turned out to be better
than standard treatments; others have either been not as good as or no better than the
treatments already being used. Although there is always a chance that a new treatment will
be disappointing, the researchers involved in a study have reason to believe that it will
be as good as, or better than, current treatments.
The patients in a clinical trial are among
the first to receive new research treatments before they are widely available. How a
treatment will work for a patient in a trial can't be known ahead of time. Even standard
treatments, although effective in many patients, do not carry sure benefits for everyone.
But, patients should choose if they want to take part in a study or not, only after they
understand both the possible risks and benefits.
The patients who
take part in clinical trials that do prove to be better treatments, have the
first chance to benefit from them. All patients in clinical trials are carefully
monitored during a trial and followed up afterwards. They become part of a
network of clinical trials carried out around the country. In this network,
doctors and researchers pool their ideas and experience to design and monitor
clinical studies. They share their knowledge from many specialties about cancer
treatment and care. Patients in these studies receive the benefit of their
expertise. At cancer centers, patients receive care from a special research
team. Through new programs, community hospitals and doctors are also coming more
and more into the research network.
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Yes. The treatments used in clinical trials
can cause side effects and risks depending on the type of treatment and the patient's
condition. Side effects vary from patient to patient.
Because clinical trials are research into
new areas of treatment, the risks involved are not always known ahead of time, though
efforts have been made to find out what they might be. For this reason, trials can carry
unknown dangers and side effects as well as hoped-for benefits. Patients need to know what
is involved in a study-what side effects may be expected-and, as much as possible, what
"unknowns" or uncertainties they may be facing.
You will be told about the treatments being
tested and will be given a form to read that discusses the risks and hoped- for benefits.
If you agree to take part, you will be asked to sign a form, called the informed consent
form. Before you sign, be sure you understand what risks you face. Ask the doctor or nurse
to explain any parts of the form or the trial that are not clear. If you do not want to be
in the trial, you may refuse. Even if you sign the form, you are free to leave the trial
at any time and can receive other available medical care.
In clinical trials, most side effects are
temporary and will gradually go away once treatment is stopped. For example, some
anticancer drugs cause hair loss and nausea and some do not. They can also affect the bone
marrow which produces blood cells. During treatment, the number of blood cells, called
blood counts, may fall too low. Since this could lead to possible infection or other
problems, patients have their blood counts checked often. Luckily, bone marrow has a great
ability to replace blood cells, so that blood counts can usually return to normal.
Some side effects in clinical trials can be
permanent and serious, even life-threatening. Also, certain side effects may not appear
until later, after the treatment itself is over. (These "late" effects may
include damage to a major organ like the heart, lungs, or kidneys; sterility; or a second
cancer.) Many cancer patients are now living longer, largely because of better treatments.
Researchers are concerned and trying to prevent late complications of treatments.
As a patient, it
can be hard to decide about your treatment. There are a number of things to
consider. Cancer is a life- threatening disease which causes symptoms of its own
that are not related to treatment. In each case, the unavoidable risks of the
cancer itself, and your condition, should be weighed against the potential risks
and benefits of a new research treatment. Standard treatments, as well as
treatments in clinical trials, can also cause side effects and risks.
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Any medical treatment can carry the
potential for side effects in some patients. Cancer treatment is particularly powerful,
because it is designed to destroy constantly dividing cancer cells. It can also affect
healthy dividing cells and this can cause side effects. The challenge to researchers has
been to develop treatments that destroy cancer cells but do not harm healthy cells .
What Is Being Done to Lessen Side Effects of
Treatment? Cancer researchers are trying to make cancer treatment more effective and
lessen its side effects for the cancer patient. Results of such efforts include:
- new anticancer drugs with less side effects;
- better antinausea medicine;
- some shorter periods of time on anticancer
- special ways to protect normal tissues during
- new methods of surgery that are less
extensive and less damaging to the body; and
- psychological support programs and
information on ways to cope during difficult times. How patients feel during and after
treatment is important.
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If You Are Thinking of
Entering A Clinical Trial . . .
Every clinical trial is designed to answer a
set of research questions. If you fit the guidelines for a trial, you may be eligible to
take part. Each study enrolls patients with certain types and stages of cancer and certain
health status. A study that involves two or more treatments can yield reliable answers
only if all the patient cases are the same so they can be compared with each other.
Before a decision is made about your
treatment (whether it is in a clinical trial or not), your type of cancer will be
diagnosed and "staged." Staging tells how far the disease has spread. Deciding
on treatment depends on many things, including the stage of the disease and your general
condition. You would most likely be referred to a trial by your own doctor or by a doctor
who knows your case. Some patients find out about trials from other sources. In any case,
you must have a reasonable understanding of your role in a research study and be freely
willing to take part in it. Ask what you can expect if you take part in a trial.
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There are many ways to find out what your
treatment choices are. Talk with your doctors and get the opinion of cancer specialists
(oncologists). You should not be afraid to ask for a second opinion. A helpful, new
computer information system called PDQ, is supported by the National Cancer Institute. PDQ
can give your doctor the latest information on clinical trials being offered around the
country for each type and stage of cancer. This ready reference is kept up to date. Your
doctor can check it from a library or personal computer.
The Cancer Information Service (CIS) is
another source of information. This program, also sponsored by the National Cancer
Institute, answers cancer-related questions from the public, cancer patients and their
families, and health professionals. If you have questions, call the toll-free number:
I-800-4-CANCER (see back cover), and you will be connected to the CIS office serving your
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This is a big question. Finding answers and
making decisions are often hard for a cancer patient. The diagnosis of cancer and deciding
what to do about it can be overwhelming, and you may be confused and upset. It is
important to discuss your options with medical experts- including your own doctor-and with
those close to you. Your personal doctor, who may be your family doctor, and cancer
specialists can counsel you about your choices for standard treatment or clinical trials.
Talk to them and ask questions about the
problems you are facing. If you understand what is going on, you can help your doctor work
with you more effectively. You may want to take a friend or relative along with you when
you talk to your doctor about your case.
Take time to ask your questions and to
discuss what you want to know. It may help you and your doctor if you plan what to ask and
write questions down ahead of time. No question is foolish. Learn what is available to
you. Find out your choices and the risks and benefits of each. Each patient is different.
You are an individual with individual needs, and your health is important. If you are a
parent of a child with cancer, of course, you have great concerns about making the best
decision for your child's care.
As you decide about treatment, if it is in a
clinical trial or not, remember that you are not alone. There are many people to help you-
doctors, nurses, social workers, clergy, your family, friends, and other patients.
Although it is YOUR decision, they can help you think about it and decide what is best for
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If you are thinking about taking part in a
clinical trial, here are some important questions to ask:
- What is the purpose of the study?
- What does the study involve? What kinds of
tests and treatments? (Find out what is done and how it is done.)
- What is likely to happen in my case with, or
without, this new research treatment? (What may the cancer do and what may this treatment
- What are other choices and their advantages
and disadvantages? (Are there standard treatments for my case and how does the study
compare with them?)
- How could the study aftect my daily life?
- What side effects could I expect from the
study? (There can also be side effects from standard treatments and from the disease
- How long will the study last? (Will it
require an extra time commitment on my part?)
- Will I have to be hospitalized? If so, how
often and for how long?
- Will I have any costs? Will any of the
treatment be free?*
- If I am harmed as a result of the research,
what treatment would I be entitled to?
- What type of long-term followup care is part
of the study?
*Costs are a major concern of patients and
families. Different arrangements and policies exist at different institutions and, of
course, insurance coverage varies. Patients should freely discuss what costs are involved
in their cases ahead of time. If you need financial aid, contact the hospital social
services office, the Cancer Information Service, or the local American Cancer Society
Chapter. They may be able to direct you to a source of help.
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Informed consent, a key part of a good
trial, is required in studies that are federally regulated or funded as well as by many
state laws. Informed consent means that as a patient, you are given information so you can
understand what is involved in a trial, including its potential benefits and risks, and
then decide freely to take part in it or not. The nature of the treatment is explained by
the doctors and nurses in the trial. You are given an informed consent form to read and
consider carefully. Ask any questions you may have. Then, if you agree to take part, you
can sign the form. Of course, you may also refuse.
The informed consent process (also discussed
on page 4) is an ongoing process. If you enter a trial, you will continue to receive any
new information about your treatment that may affect your willingness to stay in the
trial. Signing a consent form does not bind you to the study. You can still leave at any
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Whether cancer patients are in a research
study or not, they tace a new world of medical terms and procedures. For some people,
myths and fears of "experimentation" or of being a "guinea pig" come
with the idea of clinical trials. And, surely, there are fears of the unknown.
Understanding what is involved can ease some of your anxieties. Patients in a clinical
trial, for example, receive their care in the same places that standard treatments are
given-at cancer centers, hospitals, clinics, or doctors' offices.
Because a growing number of cancer
specialists are now in private practice in the community, most cancer care can be given in
an area near your home. Doctors, nurses, social workers and other health professionals
from many different specialties may help care for you. They are working together for your
good. There is consideration for your privacy and well-being.
If you join a research study, you will be
watched closely and data on your case will be carefully recorded. You may receive more
examinations and tests than are usually given. (These are to follow your progress as well
as to collect study data.) Of course, tests can carry certain risks and benefits or
discomforts of their own. Although they can be inconvenient, these tests can assure an
extra ounce of observation along the way.
During the course of a study, if it is clear
that a treatment is not in your best interest, you will be removed from the study and you
can discuss other options.
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Yes. Just as you can refuse to join a study,
you may leave a study at any time. Your rights as an individual do not change because you
are a patient in a clinical trial. You may choose to take part or not, and you can always
change your mind later, even after you enter a trial.
You may also refuse to take part in any
aspect of the research. If you have questions at any time about any part of the study, be
sure to ask your doctors. If you are not satisfied with the answers, you may consider
leaving the study. If you decide to leave, it will not be held against you. Don't be
afraid that you will receive no further care. You can freely discuss other possible
treatments and care with your doctors and nurses.
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The ethical and legal codes that govern
medical practice apply to clinical trials. In addition, most clinical research is
federally regulated or federally funded (at least in part), with built-in safeguards to
protect patients. These safeguards include regular review of the protocol (the study
plans) and the progress of each study by researchers at other places.
For example, federally funded and federally
regulated clinical trials must first be approved by an Institutional Review Board (IRB)
located at the institution where the study is to take place. IRBs, designed to protect
patients, are made up of scientists, doctors, clergy and other people from the local
community. An IRB reviews a study to see that it is well designed with safeguards for
patients, and that the risks are reasonable in relation to the potential benefits.
Federally supported or regulated studies
also go through reviews by a government agency, such as the National Cancer Institute,*
which sponsors and monitors many trials around the country
Any well-run clinical trial, whether
federally supported or not, is carefully reviewed for medical ethics, patient safety, and
scientific merit by the research institution. Every study should provide for monitoring
the data and the safety of patients on an ongoing basis.
As discussed earlier, informed consent is
also an important process that helps to protect patients.
After patients join a clinical trial and it
progresses, the doctors report the results of the trial to scientific meetings, to medical
journals whose articles are approved by experts, and to various government agencies. *The
National Cancer Institute (NCI) is the Federal Government's chief agency for cancer
research. Located at the National Institutes of Health (NIH) in Bethesda, Maryland, the
Institute funds cancer research across the country and conducts research at its own
facilities. For information about NCI trials, call: 800-638-6694 (in Maryland, call
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Things that make a sound, well-run trial to
safeguard patients include the items discussed in the previous section of this booklet.
Keeping these items in mind, here are some important questions for you to ask to find out
if a study is well run:
- What is its purpose?
- Who has reviewed and approved the study?
- Who is sponsoring the study?
- How are the study data and patient safety
- Where will information from the study go? (In
government- related research, for example, reports might go to the National Cancer
Institute and/or the Food and Drug Administration.)
For your own protection, be sure to get
satisfactory answers to these questions before you agree to take part.
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There are many kinds of clinical trials.
They range from studies of ways to prevent, detect and diagnose, control and treat cancer,
to studies of the psychological impact of the disease and ways to improve the patient's
comfort and quality of life (including pain control).
Most cancer clinical trials deal with new
treatments. These treatments often involve surgery, radiation therapy (the use of X-rays,
neutrons or other types of cell-destroying radiation), and chemotherapy (the use of
anticancer drugs). Alone, or in combination, these types of treatments can cure many
cancer patients and prolong the lives of many others. A fairly new area of cancer
treatment is biological therapy -the use of biologicals (substances produced by the body's
own cells) and biological response modifiers (substances that affect the body's natural
defense systems against disease).
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Clinical trials are carried out in phases,
each designed to find out certain information. Patients may be eligible for studies in
different phases depending on their general condition and the type and stage of their
cancer. More patients take part in the later phases of studies than in the earlier ones.
In a Phase I study, a new research treatment
is given to a small number of patients. The researchers must find the best way to give a
new treatment and how much of it can be given safely. They watch carefully for any harmful
side effects. The research treatment has been well tested in laboratory and animal
studies but no one knows how patients will react. Phase I studies may involve significant
risks for this reason. They are offered only to patients whose cancer has .spread and who
would not be helped by other known treatments. Phase I treatments may produce anticancer
effects, and some patients have been helped by these treatments.
Phase II studies determine the effect of a
research treatment on various types of cancer. Each new phase of a clinical trial depends
on and builds on intormation from an earlier phase. If a treatment has shown activity
against cancer in Phase II, it moves to Phase III. Here it is compared with standard
treatment to see which is more effective. Often researchers use standard therapy as the
base to design new, hopefully better treatments. Then in Phase III, the new treatment is
directly compared to the old one. In Phase IV studies, the new research treatment becomes
part of standard treatment in patient care. For example, a new drug that has been found
effective in a clinical trial may then be used together with other effective drugs, or
with surgery, and/or radiation therapy.
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The doctors who conduct a clinical trial
follow a carefully designed treatment plan called a "protocol." This spells out
what will be done and why. Studies are planned to safeguard the medical and psychological
health of patients as well as to answer research questions.
Some clinical trials test one research
treatment in one group of patients. Other trials compare two or more treatments in
separate groups of patients who are similar in certain ways, such as the extent of their
disease. This way, the treatment groups are alike and the results from each can validly be
One of the groups may receive standard (the
most accepted) treatment so the new treatments can be directly compared to it. The group
receiving the standard treatment is called the "control" group. For example, one
group of patients (the control group) may receive the usual surgical treatment tor a
certain cancer, while another patient group with the same type of cancer may receive
surgery plus radiation therapy to see if this improves disease control.
Sometimes, no standard treatment yet exists
for certain cancer patients. In drug studies for such cases, one group of patients might
receive a new drug and the control group, none. But no patient is placed in a control
group without treatment if there is any known treatment that would benefit that patient.
The control group is t'ollowed as often and carefully as the "treatment" group.
One of the ways to prevent the bias of a
patient or doctor t'rom influencing study results is "randomization." If a
patient agrees to be randomized, this means he or she is selected by chance to be in one
group or another. The researchers do not know which treatment is best. From what is known
at the time, any one of the treatments chosen could be of equal benet'it to the patient.
If the treatment in a trial is not helping
the patient, the patient's doctor can decide to take him or her out of the study. Of
course, the patient can decide to leave, as well, and still receive other available care.
There are regular reviews of the results of a trial and the int'ormation is shared. This
is important, because if a treatment is t'ound to be too harmful or not effective, it is
stopped. Also, when there is firm evidence that one method is better than the others in a
study, the trial is stopped and all patients in the trial are given the benefit of the new
information. Such information may help present and future patients.
Throughout a clinical study, a patient's
personal doctor will be kept informed of the patient's progress. Patients are encouraged
to maintain contact with their referring doctors.
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A nationwide effort to conquer cancer
intensified with the National Cancer Act of 1971. As a result of the National Cancer
Program, created by that legislation, more cancer patients are being cured today than ever
before, and many others are living longer with improved quality of life.
The National Cancer Program brings together
a network of researchers at many public and private institutions around the country. These
include the National Cancer Institute, cancer centers, universities, community hospitals
and private industry. Groups involving hundreds of researchers are working to discover and
put to use new knowledge to benefit the cancer patients of today and tomorrow.
Knowledge gained from research studies with
patients-clinical trials-has been essential to overall progress. Such studies have led to
increased survival for childhood cancers, Hodgkin's disease, breast, uterine, testicular
and bladder cancers, as well as others. These studies continue to play a key role in
progress against cancer.
Today, major scientific discoveries in the
laboratory are part of a revolution in biology. New tools to unravel the process of cancer
are leading to exciting new approaches against cancer. Clinical trials continue to be the
link between such basic research and patients. The goal is to translate the best of that
research into findings that directly help people.
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(ad'ju-vant kee-mother'a-pee)-One or more
anticancer drugs used in combination with surgery or radiation therapy as part of the
treatment of cancer. Adjuvant usually means "in addition to" initial treatment.
(an'ti-bod-ee)-A protein produced by a
plasma cell in the Iymphatic system or bone marrow. An antibody binds to the specific
antigen that has stimulated the immune system. Once bound, the antigen can be destroyed by
other cells of the immune system. See Immune System.
(an'ti-jen)-A substance, foreign to the
body, that stimulates the production of antibodies by the immune system. Antigens include
foreign proteins, bacteria, viruses, pollen and other materials.
-Use of biologicals (substances produced by
our own cells) or biological response modifiers (substances that affect the patient's
defense systems) in the treatment of cancer.
-Measurement of the number of red cells,
white cells, and platelets in a sample of blood.
(mair'oh)-The inner, spongy core of bone
that produces blood cells.
(kan'ser)-A general term for more than 100
diseases characterized by abnormal and uncontrolled growth of cells. The resulting mass,
or tumor, can invade and destroy surrounding normal tissues. Cancer cells from the tumor
can spread through the blood or Iymph to start new cancers in other parts of the body.
CCOP (Community Clinical Oncology Program)
-This new program links community physicians
with NCI clinical research programs, so that more cancer patients can participate in
clinical trials in their own communities. NCI has funded 62 CCOPs affiliated with over 200
hospitals in 34 states.
-The systematic investigation of the effects
of materials or methods, according to a formal study plan and generally in a human
population with a particular disease or class of diseases. In cancer research, a clinical
trial generally refers to the evaluation of treatment methods such as surgery, drugs or
radiation techniques, although methods of prevention, detection or diagnosis also may be
the subject of such studies.
(kee-mo-ther'apee)-Use of two or more
(ther'a-pee)-The use of two or more modes of
treatment-surgery, radiotherapy, chemotherapy, immunotherapy-in combination, alternately
or together, to achieve optimum results against cancer.
-In clinical studies this is a group of
patients which receives standard treatment, a treatment or intervention currently being
used and considered to be of proved effectiveness on the basis of past studies. Results in
patients receiving newly developed treatments may then be compared to the control group.
In cases where no standard treatment yet exists for a particular condition, the control
group would receive no treatment. No patient is placed in a control group without
treatment if there is any beneficial treatment known for that patient.
-Characteristic of a controlled experiment
in which neither the patient nor the attending physician knows whether the patient is
getting one or another drug or dose. In singleblind studies, patients do not know which of
several treatments they are receiving, thus preventing personal bias from influencing
their reactions and study results. In either case, the treatment can be quickly
identified, if necessary, by a special code.
-Chemical product of the endocrine glands of
the body, which, when secreted into body fluids, has a specific effect on other organs.
-A complex network of organs, cells and
specialized substances distributed throughout the body and defending it from foreign
invaders that cause infection or disease.
(im-mew-no-ther'a-pee)-A form of biological
therapy. An experimental method of treating cancer, using substances which stimulate the
body's immune defense system.
-The process in which a patient learns about
and understands the purpose and aspects of a clinical trial and then agrees to
participate. Of course, a patient may decline to participate. This process includes a
document defining how much a patient must know about the potential benefits and risks of
therapy before being able to agree to undergo it knowledgeably. (Informed consent is
required in federally conducted, funded or regulated studies as well as by many state
laws.) If a patient signs an informed consent form and enters a trial, he or she is still
free to leave the trial at any time, and can receive other available medical care.
(in-tur-feer'on)-A protein substance
produced by white blood cells and other types of cells that have been exposed to certain
viruses. In test animals, interferon has shown some activity against tumors. Studies of
its usefulness in treating some types of human cancer are under way. One of a number of
new agents available as biological therapy.
Investigational New Drug
-A drug allowed by the Food and Drug
Administration (FDA) to be used in clinical trials but not approved by the FDA for
-An investigator is the experienced clinical
researcher who prepares a protocol or treatment plan and implements it with patients.
(me-tas'ta-sis)-The transfer of disease from
one part of the body to another. In cancer, metastasis is the migration of cancer cells
from the original tumor site through the blood and Iymph vessels to produce cancers in
other tissues. Metastasis also is the term used for a secondary cancer growing at a
(met-a-stat'ik)-Cancer that has spread from
its original site to one or more additional body sites.
(mon-o-klone'al an'tibod-eez)-One of several
new substances used in biological therapy. These antibodies, all exactly alike, are
mass-produced and designed to home in on target cancer cells. Monoclonal antibodies are
products of new scientific techniques and may prove useful in both cancer diagnosis and
(mul'ti-mo-dal'i-tee ther' a-pee)-The
combined use of more than one method of treatment, for example, surgery and chemotherapy.
Oncologist (on-kol'o-jist)-A physician who is a cancer specialist.
-PDQ, supported by NCI, is a computerized
database available to physicians nationwide. Geographically matrixed, it offers the latest
information on standard treatments and ongoing clinical trials for each type and stage of
cancer. The information is easily accessible for physicians via libraries and personal
(pla-see'bo)-An inactive substance
resembling a medication, given for psychological effect or as a control in evaluating a
medicine believed to be active. It is usually a tablet, capsule, or injection that
contains a harmless substance but appears to be the same as the medicine being tested. A
placebo may be compared with a new drug when no one knows if any drug or treatment will be
(pro'to-kol)-The outline or plan for use of
an experimental procedure or experimental treatment.
, also called Radiotherapy- Treatment using
X-rays, cobalt-60, radium, neutrons, or other types of cell- destroying radiation.
(ray'dee-o-sen-si-ty'zers)- Drugs being
studied to try to boost the effect of radiation therapy.
Randomized Clinical Trials
(ran-duh'mized)-A study in which patients
with similar traits, such as extent of disease, are chosen or selected by chance to be
placed in separate groups that are comparing different treatments. Because irrelevant
factors or preferences do not influence the distribution of patients, the treatment groups
can be considered comparable and results of the different treatments used in different
groups can be compared. (There is no way at the time for the researchers to know which of
the treatments is best.) See also Clinical Trials. (It is the patient's choice to be in a
randomized trial or not.)
(ree-gresh'un)-The state of growing smaller
or disappearing; used to describe the shrinkage or disappearance of a cancer.
(ree-mish'un)-The decrease or disappearance
of evidence of a disease; also the period during which this occurs.
-The relation between the risks and benefits
of a given treatment or procedure. Institutional Review Boards (IRBs) (located where the
study is to take place) determine that the risks in a study are reasonable with respect to
the potential benefits. It is also up to the patient to decide if it is reasonable for him
or her to take part in a study.
-A secondary and usually adverse effect, as
from a drug or other treatment. For example, nausea is a side effect of some anticancer
-(See Double Blind)
-Methods used to establish the extent of a
-A treatment or other intervention currently
being used and considered to be of proved effectiveness on the basis of past studies .
-Patients in clinical trials are assigned to
one part or segment of a study-a study "arm." One arm receives a different
treatment from another.
(ther'a-pew'tik)-Pertaining to treatment.
This information comes from the National Cancer Institute.
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