diagnostics (cancer)
TRANSCRIPT
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Diagnostic Imaging
How is cancer diagnosed?
There is no single test that can accurately diagnose cancer. The complete evaluation of a
patient usually requires a thorough history and physical examination along with diagnostic
testing. Many tests are needed to determine whether a person has cancer, or if another
condition (such as an infection) is mimicking the symptoms of cancer. Effective diagnostic
testing is used to confirm or eliminate the presence of disease, monitor the disease process,
and to plan for and evaluate the effectiveness of treatment. In some cases, it is necessary to
repeat testing when a persons condition has changed if a sample collected was not of good
quality, or an abnormal test result needs to be confirmed. Diagnostic procedures for cancer
may include imaging, laboratory tests (including tests for tumor markers), tumor biopsy,
endoscopic examination, surgery, or genetic testing.
What are the different types of diagnostic imaging?
Imaging is the process of producing valuable pictures of body structures and organs. It is used
to detect tumors and other abnormalities, to determine the extent of disease, and to evaluate
the effectiveness of treatment. Imaging may also be used when performing biopsies and other
surgical procedures. There are three types of imaging used for diagnosing cancer:
transmission imaging, reflection imaging, and emission imaging. Each uses a different
process.
transmission imaging
X-rays, computed tomography scans (CT scans), and fluoroscopy are radiological
examinations whose images are produced by transmission. In transmission imaging, a
beam of high-energy photons is produced and passed through the body structure being
examined. The beam passes very quickly through less dense types of tissue such as
watery secretions, blood, and fat, leaving a darkened area on the x-ray film. Muscle
and connective tissues (ligaments, tendons, and cartilage) appear gray. Bones will
appear white.
o x-ray
X-rays are diagnostic tests that use invisible electromagnetic energy beams to
produce images of internal tissues, bones, and organs on film. X-rays may be
taken of any part of the body to detect a tumor (or cancer).
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o computed tomography scan (Also called a CT scan or computed axial
tomography or CAT scan.)
A CT scan is a diagnostic imaging procedure that uses a combination of x-rays
and computer technology to produce cross-sectional images (often called
slices), both horizontally and vertically, of the body. A CT scan shows detailed
images of any part of the body, including the bones, muscles, fat, and organs.
CT scans are more detailed than general x-rays.
o bone scan
Bone scans are pictures or x-rays taken of the bone after a radioactive
material has been injected that is absorbed by bone tissue. These scans are used
to detect tumors and bone abnormalities.
o lymphangiogram (LAG)
Lymphangiogram is an imaging study that can detect cancer cells orabnormalities in the lymphatic system and structures. It involves a dye being
injected into the lymph system.
o mammogram
A mammogram is an x-ray examination of the breast. It is used to detect and
diagnose breast disease in women who either have breast problems such as a
lump, pain, or nipple discharge, as well as for women who have no breast
complaints. Mammography cannot prove that an abnormal area is cancerous,
but if it raises a significant suspicion of cancer, a biopsy may be performed.
Tissue may be removed by needle or open surgical biopsy and examined under
a microscope to determine if it is cancer. Mammography has been used for
about 30 years, and in the past 15 years technical advancements have greatly
improved both the technique and results. Today, dedicated equipment, used
only for breast x-rays, produces studies that are high in quality but low in
radiation dose. Radiation risks are considered to be negligible.
reflection imaging
Reflection imaging refers to the type of imaging produced by sending high-frequency
sounds to the body part or organ being studied. These sound waves "bounce" off of thevarious types of body tissues and structures at varying speeds, depending on the
density of the tissues present. The bounced sound waves are sent to a computer that
analyzes the sound waves and produces a visual image of the body part or structure.
o ultrasound
Ultrasound, or sonography, is the most commonly used type of reflection
imaging. This technique uses high-frequency sound waves and a computer to
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create images, called sonograms, of blood vessels, tissues, and organs.
Sonograms are used to view internal organs as they function and to assess
blood flow through various vessels. Tumors in the abdomen, liver, and kidneys
can often be seen with an ultrasound.
emission imaging
Emission imaging occurs when tiny nuclear particles or magnetic energy are detected
by a scanner and analyzed by computer to produce an image of the body structure or
organ being examined. Nuclear medicine uses emission of nuclear particles from
nuclear substances introduced into the body specifically for the examination.
o magnetic resonance imaging (MRI)
MRI is a diagnostic procedure that uses a combination of a large magnet,
radiofrequencies, and a computer to produce detailed images of organs and
structures within the body. An MRI is often used to examine the heart, brain,liver, pancreas, male and female reproductive organs, and other soft tissues. It
can assess blood flow, detect tumors and diagnose many forms of cancer,
evaluate infections, and assess injuries to bones and joints.
o positron emission tomography (PET)
PET is a specialized radiology procedure used to examine various body tissues
to identify certain conditions. PET may also be used to follow the progress of
the treatment of certain conditions. PET is a type of nuclear medicine
procedure. This means that a tiny amount of a radioactive substance, called a
radionuclide (radiopharmaceutical or radioactive tracer), is used during the
procedure to assist in the examination of the tissue under study. Specifically,
PET studies evaluate the metabolism of a particular organ or tissue, so that
information about the physiology (functionality) and anatomy (structure) of the
organ or tissue is evaluated, as well as its biochemical properties. Thus, PET
may detect biochemical changes in an organ or tissue that can identify the
onset of a disease process before anatomical changes related to the disease can
be seen with other imaging processes such as computed tomography (CT) or
magnetic resonance imaging (MRI).
Cancer Diagnosis
How is cancer diagnosed?
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There is no single test that can accurately diagnose cancer. The complete evaluation of a patient usually requires a
thorough history and physical examination along with diagnostic testing. Many tests are needed to determine whether
a person has cancer, or if another condition (such as an infection) is mimicking the symptoms of cancer.
Effective diagnostic testing is used to confirm or eliminate the presence of disease, monitor the disease process, and
to plan for and evaluate the effectiveness of treatment. In some cases, it is necessary to repeat testing when apersons condition has changed, if a sample collected was not of good quality, or an abnormal test result needs to be
confirmed.
Diagnostic procedures for cancer may include imaging, laboratory tests (including tests for tumor markers), tumor
biopsy, endoscopic examination, surgery, or genetic testing.
What are the different types of laboratory tests?
Clinical chemistry uses chemical processes to measure levels of chemical components in body fluids and tissues.
The most common specimens used in clinical chemistry are blood and urine.
Many different tests exist to detect and measure almost any type of chemical component in blood or urine.
Components may include blood glucose, electrolytes, enzymes, hormones, lipids (fats), other metabolic substances,
and proteins.
The following are some of the more common laboratory tests:
blood tests
A variety of blood tests are used to check the levels of substances in the blood that indicate how
healthy the body is and whether infection is present. For example, blood tests revealing elevated
levels of waste products, such as creatinine or blood urea nitrogen (BUN), indicate that the kidneys
are not working efficiently to filter those substances out. Other tests check the presence of
electrolytes - chemical compounds such as sodium and potassium that are critical to the body's
healthy functioning. Coagulation studies determine how quickly the blood clots.
A complete blood count (CBC) measures the size, number, and maturity of the different blood cells
in a specific volume of blood. This is one of the most common tests performed. Red blood cells are
important for carrying oxygen and fighting anemia and fatigue; the hemoglobin portion of the CBC
measures the oxygen carrying capacity of the red blood cells while the hematocrit measures the
percentage of red blood cells in the blood. White blood cells fight infection. Increased numbers of
white blood cells, therefore, may indicate the presence of an infection. Platelets prevent the body
from bleeding and bruising easily.
urinalysisUrinalysis breaks down the components of urine to check for the presence of drugs, blood, protein,
and other substances. Blood in the urine (hematuria) may be the result of a benign (noncancerous)
condition, but it can also indicate an infection or other problem. High levels of protein in the urine
(proteinuria) may indicate a kidney or cardiovascular problem.
tumor markers
Tumor markers are substances either released by cancer cells into the blood or urine or substances
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created by the body in response to cancer cells. Tumor markers are used to evaluate how well a
patient has responded to treatment and to check for tumor recurrence. Research is currently being
conducted on the role of tumor markers in detection, diagnosis, and treatment of cancers.
According to the National Cancer Institute (NCI), tumor markers are useful in identifying potential
problems, but they must be used with other tests for the following reasons:
People with benign conditions may also have elevated levels of these substances in their
blood.
Not every person with a tumor has tumor markers.
Some tumor markers are not specific to any one type of tumor.
The following is a brief description of some of the more useful tumor markers:
prostate-specific antigen (PSA)
Prostate-specific antigen is always present in low concentrations in the blood of adult males. An
elevated PSA level in the blood may indicate prostate cancer, but other conditions such as benign
prostatic hyperplasia (BPH) and prostatitis can also raise PSA levels. PSA levels are used to evaluate
how a patient has responded to treatment and to check for tumor recurrence.
prostatic acid phosphatase (PAP)
PAP originates in the prostate and is normally present in small amounts in the blood. In addition to
prostate cancer, elevated levels of PAP may indicate testicular cancer, leukemia, and non-Hodgkins
lymphoma, as well as some noncancerous conditions.
CA 125
Ovarian cancer is the most common cause of elevated CA 125, but cancers of the uterus, cervix,
pancreas, liver, colon, breast, lung, and digestive tract can also raise CA 125 levels. Several
noncancerous conditions can also elevate CA 125. CA 125 is mainly used to monitor the treatment
of ovarian cancer.
carcinoembryonic antigen (CEA)
CEA is normally found in small amounts in the blood. Colorectal cancer is the most common cancer
that raises this tumor marker. Several other cancers can also raise levels of carcinoembryonic
antigen.
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alpha-fetoprotein (AFP)
Alpha-fetoprotein is normally elevated in pregnant women since it is produced by the fetus.
However, AFP is not usually found in the blood of adults. In men, and in women who are not
pregnant, an elevated level of AFP may indicate liver cancer or cancer of the ovary or testicle.
Noncancerous conditions may also cause elevated AFP levels.
human chorionic gonadotropin (HCG)
HCG is another substance that appears normally in pregnancy and is produced by the placenta. If
pregnancy is ruled out, HCG may indicate cancer in the testis, ovary, liver, stomach, pancreas, and
lung. Marijuana use can also raise HCG levels.
CA 19-9
This marker is associated with cancers in the colon, stomach, and bile duct. Elevated levels of CA
19-9 may indicate advanced cancer in the pancreas, but it is also associated with noncancerous
conditions, including gallstones, pancreatitis, cirrhosis of the liver, and cholecystitis.
CA 15-3
This marker is most useful in evaluating the effect of treatment for women with advanced breast
cancer. Elevated levels of CA 15-3 are also associated with cancers of the ovary, lung, and prostate,
as well as noncancerous conditions such as benign breast or ovarian disease, endometriosis, pelvic
inflammatory disease, and hepatitis. Pregnancy and lactation also can raise CA 15-3 levels.
CA 27-29
This marker, like CA 15-3, is used to follow the course of treatment in women with advanced breast
cancer. Cancers of the colon, stomach, kidney, lung, ovary, pancreas, uterus, and liver may also
raise CA 27-29 levels. Noncancerous conditions associated with this substance are first trimester
pregnancy, endometriosis, ovarian cysts, benign breast disease, kidney disease, and liver disease.
lactate dehydrogenase (LDH)
LDH is a protein that normally appears throughout the body in small amounts. Many cancers can
raise LDH levels, so it is not useful in identifying a specific kind of cancer. Measuring LDH levels can
be helpful in monitoring treatment for cancer. Noncancerous conditions that can raise LDH levels
include heart failure, hypothyroidism, anemia, and lung or liver disease.
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neuron-specific enolase (NSE)
NSE is associated with several cancers, but it is used most often to monitor treatment in patients
with neuroblastoma or small cell lung cancer
What are the different types of diagnostic imaging?
Imaging is the process of producing valuable pictures of body structures and organs. It is used to detect tumors and
other abnormalities, to determine the extent of disease, and to evaluate the effectiveness of treatment. Imaging may
also be used when performing biopsies and other surgical procedures. There are three types of imaging used for
diagnosing cancer: transmission imaging, reflection imaging, and emission imaging. Each uses a different process.
transmission imaging
X-rays, computed tomography scans (CT scans), and fluoroscopy are radiological examinations
whose images are produced by transmission. In transmission imaging, a beam of high-energy
photons is produced and passed through the body structure being examined. The beam passes very
quickly through less dense types of tissue such as watery secretions, blood, and fat, leaving a
darkened area on the x-ray film. Muscle and connective tissues (ligaments, tendons, and cartilage)
appear gray. Bones will appear white.
x-ray
X-rays are diagnostic tests that use invisible electromagnetic energy beams to produce
images of internal tissues, bones, and organs on film. X-rays may be taken of any part of
the body to detect tumor (or cancer) cells.
computed tomography scan (Also called a CT scan or computed axial tomography
or CAT scan.)
A CT scan is a diagnostic imaging procedure that uses a combination of x-rays and
computer technology to produce cross-sectional images (often called slices), both
horizontally and vertically, of the body. A CT scan shows detailed images of any part of thebody, including the bones, muscles, fat, and organs. CT scans are more detailed than
general x-rays.
bone scan
Bone scans are pictures or x-rays taken of the bone after a dye has been injected that is
absorbed by bone tissue. These scans are used to detect tumors and bone abnormalities.
lymphangiogram (LAG)
Lymphangiogram is an imaging study that can detect cancer cells or abnormalities in the
lymphatic system and structures. It involves a dye being injected into the lymph system.
mammogram
A mammogram is an x-ray examination of the breast. It is used to detect and diagnose
breast disease in women who either have breast problems such as a lump, pain, or nipple
discharge, as well as for women who have no breast complaints. Mammography cannot
prove that an abnormal area is cancerous, but if it raises a significant suspicion of cancer, a
biopsy may be performed. Tissue may be removed by needle or open surgical biopsy and
examined under a microscope to determine if it is cancer. Mammography has been used for
about 30 years, and in the past 15 years technical advancements have greatly improved
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both the technique and results. Today, dedicated equipment, used only for breast x-rays,
produces studies that are high in quality but low in radiation dose. Radiation risks are
considered to be negligible.
reflection imaging
Reflection imaging refers to the type of imaging produced by sending high-frequency sounds to the
body part or organ being studied. These sound waves "bounce" off of the various types of body
tissues and structures at varying speeds, depending on the density of the tissues present. The
bounced sound waves are sent to a computer that analyzes the sound waves and produces a visual
image of the body part or structure.
ultrasound
Ultrasound, or sonography, is the most commonly used type of reflection imaging. This
technique uses high-frequency sound waves and a computer to create images, called
sonograms, of blood vessels, tissues, and organs. Sonograms are used to view internal
organs as they function and to assess blood flow through various vessels. Tumors in the
abdomen, liver, and kidneys can often be seen with an ultrasound.
emission imaging
Emission imaging occurs when tiny nuclear particles or magnetic energy are detected by a scanner
and analyzed by computer to produce an image of the body structure or organ being examined.
Nuclear medicine uses emission of nuclear particles from nuclear substances introduced into the
body specifically for the examination. Magnetic resonance imaging (MRI) uses radio waves with a
machine that creates a strong magnetic field that in turn causes cells to emit their own radio
frequencies.
magnetic resonance imaging (MRI)MRI is a diagnostic procedure that uses a combination of a large magnet, radiofrequencies,
and a computer to produce detailed images of organs and structures within the body. An
MRI is often used to examine the heart, brain, liver, pancreas, male and female
reproductive organs, and other soft tissues. It can assess blood flow, detect tumors and
diagnose many forms of cancer, evaluate infections, and assess injuries to bones and
joints.
There is no single test that can accurately diagnose cancer. The complete evaluation of a patient usually requires a
thorough history and physical examination along with diagnostic testing. Many tests are needed to determine whether
a person has cancer, or if another condition (such as an infection) is mimicking the symptoms of cancer.
Effective diagnostic testing is used to confirm or eliminate the presence of disease, monitor the disease process, and
to plan for and evaluate the effectiveness of treatment. In some cases, it is necessary to repeat testing when a
persons condition has changed, if a sample collected was not of good quality, or an abnormal test result needs to be
confirmed.
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Diagnostic procedures for cancer may include imaging, laboratory tests (including tests for tumor markers), tumor
biopsy, endoscopic examination, surgery, or genetic testing.
What are the different types endoscopic examinations?
An endoscope is a small, flexible tube with a light and a lens on the end used to look into the esophagus, stomach,duodenum, colon, or rectum. It can also be used to take tissue from the body for testing or to take color photographs
of the inside of the body. Cystoscopes, colonoscopes, and sigmoidoscopes are types of endoscopes and are
described below:
colonoscopy
Colonoscopy is a procedure that allows the physician to view the entire length of the large intestine,
and can often help identify abnormal growths, inflamed tissue, ulcers, and bleeding. It involves
inserting a colonoscope, a long, flexible, lighted tube, in through the rectum up into the colon. The
colonoscope allows the physician to see the lining of the colon, remove tissue for further
examination, and possibly treat some problems that are discovered.
endoscopic retrograde cholangiopancreatography (ERCP)
ERCP is a procedure that allows the physician to diagnose and treat problems in the liver,
gallbladder, bile ducts, and pancreas. The procedure combines x-ray and the use of an endoscope -
a long, flexible, lighted tube. The scope is guided through the person's mouth and throat, then
through the esophagus, stomach, and duodenum. The physician can examine the inside of these
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organs and detect any abnormalities. A tube is then passed through the scope and a dye is injected,
which will allow the internal organs to appear on an x-ray.
esophagogastroduodenoscopy (Also called EGD or upper endoscopy.)An EGD (upper endoscopy) is a procedure that allows the physician to examine the inside of the
esophagus, stomach, and duodenum. A thin, flexible, lighted tube, called an endoscope, is guided
into the mouth and throat, then into the esophagus, stomach, and duodenum. The endoscope
allows the physician to view the inside of this area of the body, as well as to insert instruments
through a scope for the removal of a sample of tissue for biopsy (if necessary).
sigmoidoscopy
A sigmoidoscopy is a diagnostic procedure that allows the physician to examine the inside of a
portion of the large intestine, and is helpful in identifying the causes of diarrhea, abdominal pain,
constipation, abnormal growths, and bleeding. A short, flexible, lighted tube, called a
sigmoidoscope, is inserted into the intestine through the rectum. The scope blows air into the
intestine to inflate it and make viewing the inside easier.
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cystoscopy (Also called cystourethroscopy.)
An examination in which a scope, a flexible tube and viewing device, is inserted through the urethra
to examine the bladder and urinary tract for structural abnormalities or obstructions, such as
tumors or stones. Samples of the bladder tissue may be removed through the cystoscope for
examination under a microscope in the laboratory.
Before Undergoing Genetic Testing
MORE INFORMATION
DNA Testing
Types of Genetic Testing
Uses of Genetic Testing
Testing for mutations in genes that give an increased risk for cancer is complicated. Below is a description of
concepts that are important to understand when considering cancer susceptibility gene testing.
You may wish to speak with your physician or healthcare provider, or obtain a referral to a genetic counselor, to find
out about specific testing availability applicable to your situation.
Inquire about laboratory testing methods.
Testing methods vary from laboratory to laboratory and may affect the sensitivity of testing (the
likelihood that the lab will identify a mutation in the gene if there is a mutation present). Different
laboratory studies have the ability to detect different types of mutations. Accuracy will therefore
vary, depending upon the type of genetic testing method performed. Sometimes the type of tissue
studied also affects the likelihood of finding a mutation (i.e., tumor versus blood sample). Also,
some families may have a mutation in a gene, but the mutation is not detectable with the current
technology. In these cases, genetic testing may give a false negative result - one that indicates a
normal result when there actually is a problem.
Not all persons with what appears to be an inherited cancer will have a mutation. Reasons
for this include:
The accuracy of testing is not 100 percent.
Testing is not available for all genes associated with a hereditary cancer.
A mutation is present in the family, however, there is not yet testing available to identify it.
The individual tested in a family has developed cancer through a nongenetic mechanism
(i.e., a sporadic case), while the other cases in the family are due to a germline mutation.
The family does not have inherited cancer in spite of a clinical presentation that suggests a
genetic basis. Some such families may be the result of incorrect reporting of cancer
diagnoses in the family.
If genetic testing is done and no mutation can be identified in an affected family member
or members (i.e., one with cancer), testing unaffected relatives for the same gene will
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not help in clarifying cancer risks.
In this situation relatives of the affected person would remain at increased risk to develop cancer by
virtue of their family history.
Consider the implications of testing results:
If a person is mutation positive:
The likelihood of developing various cancers depends upon the gene in which the mutation is found
and in some cases, where in the gene the mutation is located.
Other genes and environmental risks factors may modify cancer risk.
Test results give a probability, not certainty, of cancer development and do not indicate
when cancer may develop or the stage/grade of a potential tumor.
Test results may help a person to be proactive about cancer surveillance or preventative
measures.
Test results may not change recommendations for medical management or cancer
surveillance.
If a person is mutation negative:
If there is a known mutation in the family, then he/she is not at increased risk of
developing cancer based on the family history but is at general population risk. If the
individual tested belongs to a particular ethnic group where common mutations have been
identified, then relatives should consider testing for all ethnic-specific mutations, not just
the one present in the family.
If there is not a known mutation, a negative test result is uninformative. The family may
have a mutation in the gene tested that is not detectable with the current technology or a
mutation in a different gene, since many cancer syndromes are genetically heterogeneous
(caused by mutations on one of several different genes).
If a variant of uncertain significance is found:
In this case, an alteration in the DNA of a gene has been identified, but it is unknown
whether the alteration will actually affect the function of the gene and, as such, influence
cancer risk. Further studies may be indicated (if available). If a significant family history is
present, such a result does not rule out a hereditary cancer syndrome in a family.
Consider the psychosocial implications of testing.
Increased or decreased emotional distress may be experienced after testing for mutations in cancer
susceptibility genes. Relationships with family members may change, particularly if one person is
mutation positive, while another is mutation negative. Some individuals experience guilt when they
are the only person in their family without a mutation. Communication between family members can
improve or stop altogether depending upon test results. It is important to try to anticipate potential
problems in the family related to testing before proceeding.
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Consider the economic impact.
Testing for cancer susceptibility genes may/may not be covered by insurance, and can be costly.
Check with your insurance company about coverage prior to having testing performed. Some
laboratories perform testing for free or for a nominal fee, if part of a research study. Additionally,
programs are sometimes available to assist with covering the cost of genetic testing, depending
upon the laboratory.
Consider the risks of genetic discrimination.
Many people are concerned about the risk for genetic discrimination. Genetic discrimination is when
a person is discriminated against based on their genetic information alone. An example of genetic
discrimination would be if an insurer were to increase your premiums because they found out you
carry a mutation that increases your risk to develop cancer, even though you do not currently have
cancer and may not develop the disease. In this situation, information about legislation which
provides protection against genetic discrimination in health insurance, life insurance, and
employability at the state level can be found at the National Human Genome Research Institute on
the Online Resources page of this website.
On the federal level, the Health Insurance Portability and Accountability Act of 1996 provides some
protection against genetic discrimination with regard to health insurance for individuals with group
policies.
Remember that testing options change.
Remember that technology is rapidly advancing. If you are a person for whom no testing currently
exists, testing options may become available in the near future.
Take your time.
Do your homework and be sure to take the time to explore the above issues before undergoing
testing for mutations in cancer susceptibility genes, in order to fully understand the implications of
your test results. Remember, genetic testing is a personal choice, and is not for everyone. Only youcan decide what is right for you
How is cancer diagnosed?
There is no single test that can accurately diagnose cancer. The complete evaluation of a patient usually requires a
thorough history and physical examination along with diagnostic testing. Many tests are needed to determine whether
a person has cancer, or if another condition (such as an infection) is mimicking the symptoms of cancer.
Effective diagnostic testing is used to confirm or eliminate the presence of disease, monitor the disease process, and
to plan for and evaluate the effectiveness of treatment. In some cases, it is necessary to repeat testing when a
persons condition has changed, if a sample collected was not of good quality, or an abnormal test result needs to beconfirmed.
Diagnostic procedures for cancer may include imaging, laboratory tests (including tests for tumor markers), tumor
biopsy, endoscopic examination, surgery, or genetic testing.
What are the different types of tumor biopsies?
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A biopsy is a procedure performed to remove tissue or cells from the body for examination under a microscope.
Some biopsies can be performed in a physician's office, while others need to be done in a hospital setting. In
addition, some biopsies require use of an anesthetic to numb the area, while others do not require any sedation.
Biopsies are usually performed to determine whether a tumor is malignant (cancerous) or to determine the cause of
an unexplained infection or inflammation. The following are the most common types of biopsies:
endoscopic biopsy
This type of biopsy is performed through a fiberoptic endoscope (a long, thin tube that has a close-
focusing telescope on the end for viewing) through a natural body orifice (i.e., rectum) or a small
incision (i.e., arthroscopy). The endoscope is used to view the organ in question for abnormal or
suspicious areas, in order to obtain a small amount of tissue for study. Endoscopic procedures are
named for the organ or body area to be visualized and/or treated. The physician can insert the
endoscope into the gastrointestinal tract (alimentary tract endoscopy), bladder (cystoscopy),
abdominal cavity (laparoscopy), joint cavity (arthroscopy), mid-portion of the chest
(mediastinoscopy), or trachea and bronchial system (laryngoscopy and bronchoscopy).
bone marrow biopsy
This type of biopsy is performed either from the sternum (breastbone) or the iliac crest hipbone
(the bone area on either side of the pelvis on the lower back area). The skin is cleansed and a local
anesthetic is given to numb the area. A long, rigid needle is inserted into the marrow, and cells are
aspirated for study; this step is occasionally uncomfortable. A core biopsy (removing a small bone
'chip' from the marrow) may follow the aspiration.
excisional or incisional biopsy
This type of biopsy is often used when a wider or deeper portion of the skin is needed. Using a
scalpel (surgical knife), a full thickness of skin is removed for further examination, and the wound is
sutured (sewed shut with surgical thread). When the entire tumor is removed, it is called excisional
biopsy technique. If only a portion of the tumor is removed, it is called incisional biopsy technique.Excisional biopsy is often the method usually preferred when melanoma (a type of skin cancer) is
suspected.
fine needle aspiration (FNA) biopsy
This type of biopsy involves using a thin needle to remove very small pieces from a tumor. Local
anesthetic is sometimes used to numb the area, but the test rarely causes much discomfort and
leaves no scar. FNA is not used for diagnosis of a suspicious mole, but may be used to biopsy large
lymph nodes near a melanoma to see if the melanoma has metastasized (spread). A computed
tomography scan (CT or CAT scan) - an x-ray procedure that produces cross-sectional images of the
body - may be used to guide a needle into a tumor in an internal organ such as the lung or liver.
punch biopsy
Punch biopsies involve taking a deeper sample of skin with a
biopsy instrument that removes a short cylinder, or "apple
core," of tissue. After a local anesthetic is administered, the
instrument is rotated on the surface of the skin until it cuts
through all the layers, including the dermis, epidermis, and the
most superficial parts of the subcutis (fat).
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shave biopsy
This type of biopsy involves removing the top layers of skin by shaving it off. Shave biopsies are
also performed with a local anesthetic.
skin biopsy
Skin biopsies involve removing a sample of skin for examination under the microscope to determine
if melanoma is present. The biopsy is performed under local anesthesia. The patient usually just
feels a small needle stick and a little burning for about a minute, with a little pressure, but no pain.
http://cancer.stanford.edu/information/cancerDiagnosis/tumorBiopsy.html
http://cancer.stanford.edu/information/cancerDiagnosis/tumorBiopsy.htmlhttp://cancer.stanford.edu/information/cancerDiagnosis/tumorBiopsy.html