When
a person shows symptoms of cancer, it is in his or her best interest to see a
doctor immediately. Though the symptoms he or she may be experiencing are a
sign of the presence of cancer, there is no way of knowing for sure until a
doctor performs a proper diagnosis. Diagnosing cancer may require several tests
to be performed, including blood tests and x-rays. When each successive leads a
doctor to believe that cancer is present, the doctor will then perform a
biopsy. A biopsy is considered, in most cases, to be the sure way to tell if a
patient has developed cancer or not. Imaging tests on the other hand, such as
x-rays and MRIs, can show the size and spread of the cancer. CT
Scan:
A CT scan, also known as a computed tomography, is an advanced x-ray imaging
tool, which is capable of taking multiple image cross sections of a patient's
body. A CT scan will show a patient's soft tissues, blood vessels, and bones.
CT scans are capable of picking up images which cannot be shown on a normal
x-ray, and as a result, a CT scan is an instrumental tool for finding tumors
which would normally go unnoticed. A CT scan uses radio waves to pick up images
inside a patient, and though many believe that CT scans come with long-term
negative effects, the procedure is considered to be relatively safe. In fact,
most researchers feel that the benefits of CT scans greatly outweigh any chance
of negative effects from receiving one. Transvaginal
ultrasound Breast
ultrasound Transrectal
ultrasound Endoscopic
ultrasound The
endoscopic ultrasound is especially important because it is a smaller version
of the ultrasound attached to a device called an endoscope. The endoscope can
be inserted into the air passages or esophagus of a patient through the mouth
or nose. This can be used to find a variety of different cancers, such as
esophageal cancer, pancreatic cancer, or lung cancer. It is more effective than
placing an ultrasound device outside of a person's skin because it gets closer
and as a result, it picks up more detailed images. PET
Scan: A
PET scan is a very useful tool in diagnosing cancer in patients. In most cases,
PET scans are used to diagnose tumors, heart disease, and infections of the
nervous system. A PET scan uses radiation to produce a very detailed image of
the part of the body that is being examined. Different tissues and nerves are
usually highlighted by a spectrum of contrasting colors so that they can be
easily distinguished and identified. Normally, a tumor will produce a different
color than surrounding healthy tissue. PET scans are also useful because they
can be combined with CT scans so that a clearer, more defined image can be
produced for examination. There
are some disadvantages of a PET scan. It uses about the same amount of
radiation as having two x-rays at once. Though this is a relatively low amount
of radiation, especially compared to a CT scan, this can come with some risks
for people who are exposed to radiation at work or other places. Also, PET
scans cost a lot of money as well as the machines needed to perform the scan
are very expensive, limiting their use. Blood
Tests
Blood tests are very useful to physicians in assisting the cancer diagnosis of
a patient. There are many blood tests that can be done, each detecting the presence
and levels of chemicals within the patient's blood. If a level of a certain
chemical is above or below normal, a doctor can usually narrow down the reasons
for this be attributing its cause to one or two organs. This may mean that
something is wrong with the organ, and a cancer may be present. Irregular blood
levels do not always mean that cancer has developed inside a person, as the
irregular levels may be caused by infections or other reasons. For this reason,
blood tests are only used to help narrow down possible reasons if a patient is
experiencing symptoms. Complete
Blood Count Blood
Protein Test Tumor
Marker Test
Biopsy There
are several different ways a biopsy can be performed. In any of these types of
procedures, a biopsy involves taken a sample of tissue from an area that a
doctor believes may be cancerous or contain cells that are precancerous. The
tissue sample is then examined under a microscope to determine the cause of
symptoms. If enough tissue samples are collected and a pathologist diagnoses
the sample, the results of the biopsy should be conclusive and accurate. This
is usually the final judgement when cancer is suspected to be present in a
patient. Years
ago, technology only allowed biopsies to be performed through surgery, which
was usually invasive in nature. This meant that the patient needed time to
recover after the biopsy and the surgery was often risky. Today, biopsies can
be performed while avoiding this invasive technique through several different
methods. Fine
Needle Aspiration Core
Needle Biopsy Endoscopic
Biopsy Excisional
Biopsy Punch
Biopsy Some
biopsies are done during other diagnosing techniques. An endoscopic biopsy is
done while a doctor examines a person's internal organs through an endoscope. A
biopsy can also be done after a tumor is removed from a patient to determine
the nature of the tumor and whether or not it is malignant.
A pap smear, often referred to as a pap test, is a diagnostic method involving
the removal of cells from the vagina, uterus, and cervix to be examined under a
microscope. A specially trained pathologist can then determine whether or not
the cells that were removed are abnormal. If they are found to be
abnormal, they may be in a precancerous stage and treatment can be performed to
prevent cancer from forming. The most common form of cancer which can be found
from a pap smear is cervical cancer, caused by the human papilloma virus. A pap
smear, while essential for diagnostic purposes, is also a common screening
test, performed routinely on women by gynecologists. With
the development of the pap smear test, cervical cancer cases have dropped
dramatically by over 70 percent. Using this diagnostic test, the five year
survival rate for cases of cervical cancer, or precancerous conditions which
could lead to cancer, are about 90 percent. Most cases of advanced forms of
cervical cancer are due to a woman not receiving regular pap smear tests.
The reason why doctors do not perform a biopsy right from the start is because
they need more information first so that they can pinpoint the problematic
area. First, the doctor may begin imaging test depending on the nature and
location of the patient's symptoms. The imaging test will help show
abnormalities that may be present in the area where the symptoms are
experienced. In addition, a doctor may make a decision to perform a blood test
as well. A lot of information can be gathered from a blood test. The content of
the blood will show how well each organ in the body is working and if there are
any abnormalities, the problem can usually be pinpointed to one organ or area
of the body. Once a doctor has discovered an abnormality using these methods,
successive imaging tests can provide further detail in that location. A biopsy
can then be performed. The biopsy can usually be tough to perform and doctors
usually avoid invasive procedure before they know enough information. In some
cases, imaging tests and biopsies can be performed all in one procedure.
Imaging Tests
There
are several types of imaging tests that can be performed on patients, all
utilizing different technologies and capabilities. They all have advantages and
disadvantages, while some can only be used on certain parts of the body. The
decision to use one or over another depends on the situation of the patient.
MRI Scan:
An MRI scan is a type of imaging technique which allows a doctor to observe a
detailed image of the internal structure of the body. The MRI scan has proven
to be a useful imaging technology, developed in the 1970s as an alternative to
CT scans. The contrast between different types of tissues and bones is
unparalleled to other imaging techniques and is preferred by a lot of doctors.
In addition, MRI tests are considered to be safer as well because they do not
use potentially dangerous ionizing radiation to create images which CT scans
use. Utilizing the high hydrogen content of organisms, MRIs use powerful
magnets to align the nuclear magnetization of the hydrogen atoms. Then radio
frequency fields are activated, changing the alignment of the magnet, and in
turn, rotating the magnetic fields of the hydrogen atoms. This rotation is then
picked up by the MRI, creating the detailed images.
The MRI machine consists of three main components--The primary magnet, gradient
magnets, and the coil. The primary magnet is the largest part of the machine
and is responsible for creating the strong magnetic field that wraps around the
patient. The magnetic field is about 1.5 to 3 Tesla, about 20,000 greater than
the strength of earth's magnetic field. The gradient magnets are three smaller
magnets which fine-tune the magnetic field to specific parts of the body. The
coil wraps around the area of the body which is being imaged. It is responsible
for emitting the radiofrequency, allowing the image to be formed. These
machines are operated by MRI technicians, and can be used for basic MRI scans
and MRI contrast scans as well.
The primary use of a CT scan is to scan and image the area from the chest to
the abdomen. Its unique ability to image organs, bone, and blood vessels makes
it instrumental for finding cancers early. CT scans have proven to be an
effective tool against certain forms of extremely deadly cancers. These include
lung cancer, which is normally found in later stages, and pancreatic cancer,
also found in later stages. The CT scan could help doctors find these cancers
in their earlier, treatable forms. In addition, CT scan technology is being
improved all the time, allowing for more advanced images to be taken and in a
quicker amount of time. CT scans take only a fraction of the amount of time to
complete than an MRI scan.
Ultrasound:
An ultrasound is a device that is used in a variety of ways so that doctors can
examine the inside structure of a person's body. It uses sound waves which are
of a frequency well beyond what a human ear can pick up. The sound waves
deflect off organs, bones and other structures inside a patient's body and a
computer converts these "echoes" into an image that is placed on a
monitor. An ultrasound is useful in cancer diagnosis because sound waves
generally bounce off of tumors in a different manner and is displayed differently
on the monitor. There are several types of ultrasounds that have been developed
to examine parts of the human body for cancer:
The following are different blood tests that are performed to help detect the
presence of cancer:
Pap Smear