TECHNOLOGIES IN CANCER TREATMENT

Cancer has become very prevalent in today’s society. Technologies to diagnose and treat this horrible disease have become very high tech allowing doctor’s to see the tumours and treat them in their earliest stages.

This report investigates some of the technologies used to both diagnose and treat different forms of cancer.

CT Scan

The CT Scan (Computerized Tomography Scan) is used to locate tumours in the body. It combines many x-ray images with the help of a computer to make cross sectional images and three dimensional pictures of any part of the body.

When the CT Scan is administered it is often done with the aid of an injection of a contrast material which helps to highlight the organs of the body and make them stand out on the x-ray

images. This also makes things like tumours stand out on the x-ray images making them easier to observe.

The results obtained from the CT Scan can be used for surgeons so that they know exactly where they are going to be removing a tumour from or for radiation oncologists so that they know the exact placement of the radiation for radiation treatment.

The procedure for having a CT Scan is quite simple. The patient is injected intravenously with the contrast material. He or she then lies on a thin bed with his or her arms lifted over the head. The bed is then slid into the CT Scanner where the x-rays are taken. The procedure is short and is painless.

A CT Scanner:

PET Scan

A PET Scan (Positron Emission Tomography Scan) is a type of imaging test that creates three dimensional images through a circular arrangement of detectors that pick up patterns of radioactivity from a pharmaceutical introduced into the body that allows doctors to see how organs are functioning. The PET Scan looks at your body at the cellular level where changes initiate making it easier to diagnose cancers at an earlier stage.

A radioactive material called a radiotracer is injected into the patient like with the CT Scan in order to make the organs and cells stand out.

PET Scans can detect cancers and the effect that they are having on neighbouring tissue and organs, assisting doctors in their form of treatment and helping surgeons decide the amount of tissue around a cancer to be removed.

The procedure for a patient having a PET Scan is a simple one. The patient is injected with the radioactive radiotracer. They then wait for approximately one hour for it to spread throughout the body. At this time the patient goes to the PET Scanner. Here the procedure is much the same as with a CT Scan. The patient lies on a

thin bed with his or her arms or their head. The bed slowly moves into the PET Scanner where the pictures are taken. Because the pictures that are taken are more detailed and a different process than the x-rays used in CT Scans, PET Scans take longer to do, between 20 minutes to 1 hour or longer. This also depends on how much of the body is being scanned.

http://www.youtube.com/watch?v=XUk6Krq1Aog

A PET Scanner:

MRI

An MRI (Magnetic Resonance Imaging) is a scan that uses magnetism and radio waves to produce images in a computer. An MRI Scanner is a large tube surrounded by a large circular magnet. The magnet creates a strong magnetic field that aligns the protons in hydrogen atoms in the body and then they are exposed to a beam of radio waves. This spins the protons of the body, producing a signal that is picked up by the receiver in the MRI

machine. The image is received by a computer and an image is produced. The image is quite detailed allowing for easier diagnosis.

For most scans a contrast agent is used to highlight organs.

MRI Scans can be used to find cancer tumours as well as to check the progress of treatment by checking the size of tumours as compared to previous MRI Scans. Because the results are so detailed a minute measurement of just

millimetres is possible. Because the MRI Scanner is a large magnet

patients with any metal implants cannot have a scan done. The metal in the person’s body would give false readings on the test and any metal within the area being photographed could actually move such as pacemakers, metal clips or pins and metal clips around the eyes.

The procedure for an MRI is very similar to the CT SCAN and PET Scan. A contrast agent is

injected intravenously. The patient lies on a thin bed. Since cancer related MRIs are usually done to detect brain tumours the patient’s head is immobilized as it is imperative that there is no movement during the procedure. Should there be any movement the whole thing will have to be repeated. The bed is then slid into the tube which is very small, much smaller than the CT and PET Scanners. Some patients who are claustrophobic have a lot of trouble

and are therefore given something for anxiety before the scan. The test can take up to 1 ½ hours. During the time that the machine is taking photographs it is very noisy and, to some, uncomfortable.

http://www.youtube.com/watch?v=H5q79R9C-mk

An MRI Machine:

External Beam Radiation Therapy

Radiation therapy is used to shrink tumours and kill the cancer cells within them by destroying the DNA within the cells. When the DNA is destroyed the cell dies and the body eliminates it through its natural processes.

External Beam Radiation machines use x-rays and gamma rays for the process.

The treatment not only kills cancer cells but healthy cells around it as well. This is why CT Scans are done before hand to find the exact

location of the tumour so that the radiation location can be pinpointed exactly, reducing damage to surrounding healthy tissue as much as possible.

Radiation therapy can be given to shrink tumours that cannot be operated on. It is also used after surgery and applied to the area where the tumour was to kill any potential cancer cells that were left behind. This is done as a preventative measure.

Treatments are normally given once a day for six to eight weeks. Treatments do not last long, approximately five to ten minutes. There are some side effects to the radiation treatment depending on the location in your body that the radiation is being given, things like dry mouth and loss of the ability to taste foods to diarrhea. All experience burns on the skin that look like a sunburn and the skin eventually turns a brownish colour and peels off.

An External Beam Radiation Machine:

References

National Cancer Institute. (n.d.) Radiation Therapy for Cancer Retrieved from http://www.cancer.gov/cancertopics/factsheet/Therapy/radiation

Cleveland Clinic (n.d.) PET CT Retrieved from http://my.clevelandclinic.org/imaging-institute/imaging-services/pet-scan-hic-pet-scan.aspx

Positron Emission Tomography (PET) Scan (n.d.) Retrieved from http://www.cancer.ca/en/cancer-information/diagnosis-and-treatment/tests-and-procedures/positron-emission-tomography-pet-scan/?region=on

CT Scan (Computerized Tomography, CAT Scan) (n.d.) Retrieved from http://www.medicinenet.com/cat_scan/article.htm

Computed Tomography (CT) – Body (n.d.) Retrieved from http://www.radiologyinfo.org/en/info.cfm?pg=bodyct

Magnetic Resonance Imaging (MRI Scan) Retrieved from http://www.medicinenet.com/mri_scan/article.htm