Importance of PET scan for Cancer Patients
A positron emission tomography (PET) scan is an imaging test that helps to reveal how your organs and tissues are functioning. The PET scan uses a special dye containing radioactive tracer. This tracer is either inhaled, swallowed or injected into a vein which helps your doctor to see how well your organs and tissues are working. The traces collected at the area where is a high rate of chemical activities, which corresponds to the area of disease. While doing PET scan these areas show up as a bright spot.
What PET scan detect?
- PET scan is most often used to diagnosed cancer.
- Heart problem such as coronary artery disease and damage to the heart after a heart attack.
- Brain disorder such as brain tumors, memory disorders, and seizures and other nervous system disorder.
A PET scan is used for
- Measure vital function blood flow, oxygen use, how your body uses sugar, and much more, doctors identify organs and tissues that are not working properly.
- Evaluate how well the treatment is working on the patient. Allowing to adjusted, if necessary.
- Detect Tumor cells for initial staging.
Cancer – Cancer has a higher metabolic rate than noncancerous cells. because of high-level chemical activity, the cancer cell shows a bright spot on the PET scan. PET scan is useful for:
- Detecting the cancer.
- To see whether the cancer is spread.
- To see the cancer treatment is working.
- Checking for cancer recurrence.
After the cancer treatment, a CT scan may show that some sign of cancer is left but it may not be an active disease. It could be a scar tissue left after the treatment. A PET scan can demonstrate whether this tissue is active cancer or not.
Risk
During PET scan a radioactive drug will be put in your body but the exposure to harmful radiation is minimal. The amount of radiation in tracer is small, so the risk to your body is low.
The tracer might:
- In rare instances, a tracer causes a major allergic reaction.
- If you are pregnant you will expose your unborn baby to radiation.
- If you are breast feeding you will expose your child to radiation.
The tracer is glucose with radioactive components attached. This makes easy to your body to eliminate the tracers.
It is possible to have an allergic reaction, people who are allergic to iodine, aspartame, or saccharin should alert their doctor first.
People who have an allergic reaction to iodine trace include people with:
- Allergies.
- Asthma.
- Heart disease.
- Dehydration.
- Multiple myeloma.
- Kidney disease.
How to Prepare for PET scan
Your doctor will provide you the complete information on how to prepare for PET scan. Twenty-four hours before your PET scan your doctor may ask you to stick on low- carbohydrate. Food and beverages, you should avoid include:
- Cereal.
- Pasta.
- Bread.
- Rice.
- Milk and yogurt.
- Fruit and fruit juices.
- Alcohol.
- Caffeinated beverages.
- Sweet candy’s, mint or chewing gum.
The food you can eat
- No starchy vegetables.
- Meat.
- Tofu.
- Nuts.
On the day of the PET scan, you need to stop eating before 4-6 hours before the PET scan. You can drink water during this time. You may be asked to strenuous physical activity like exercise before 24 hours of the procedure. If you are claustrophobic then tell the staff in advance, so they will take extra care to make sure you’re comfortable.
Other condition:
You should tell your doctor about your medical condition:
- If you’re breastfeeding – you need to pump and store their milk 24 before the procedure. also, you are not allowed to breastfeed after 24 hours of the procedure.
- If you are pregnant – You should tell your doctor about your pregnancy as this test may be unsafe for your baby.
- If you have diabetes – fasting forehand could affect your blood sugar, your doctor will give you special instruction about your meal timings. You’ll likely be told to take a normal dose of your insulin and eat a light meal 4 hours before the procedure.
How is a PET scan performed?
Before the scan, you will get tracer to drink, or through a gas inhale, or through a vein in your arms. The body needs to absorb the trace, so you have to wait one hour before the scan begins. The duration of waiting time depends on how full your body absorbs the trace and on the area of the body being scanned.
During the scan, you will be lying on a narrow table attached to a PET machine, which looks like a giant letter “O”. the table glides slowly into the machine so the scan can be conducted. The procedure last approx. 30 to 45 minutes. You need to remain still during the scan, the technician will guide you. You may ask to hold a breath for several seconds. when all the necessary images have been taken you will be slide out the machine and the procedure is complete.
Advantages of PET scan
- PET scan is very powerful tool, which help determine and diagnose the stages of many type cancer.
- Type of cancer include: Lunge cancer, head and neck, lymphoma, esophageal, melanoma, breast, thyroid, cervical, pancreatic and brain cancer.
- Pet scan may identify the optimal biopsy location.
- PET scan may help your doctor to choose the most appropriate treatment plan for you.
- It helps doctors to know whether chemotherapy and other treatments are working as intended.
- PET scan is the currently most effective means of detecting recurrence of cancer.