What Is Nuclear Medicine?

• Nuclear medicine leverages radioactive tracers to obtain diagnostic information
• Radiation is emitted from inside the human body c.f. transmitted radiation in x-ray imaging
• Radioactive Tracers trace the paths of various biochemical molecules in our body and hence can obtain functional information about the body’s workings (i.e. physiology)

How Nuclear Medicine Works?

Nuclear medicine exams use a radioactive material called a radiopharmaceutical or radiotracer. This material is injected into the bloodstream, swallowed or inhaled as a gas. The material accumulates in the area of your body under examination, where it gives off a small amount of energy in the form of gamma rays.

DIAGNOSTICS

What is PET-CT ?

A PET scan demonstrates the biological function of the body before anatomical changes take place, while the CT scan provides information about the body's anatomy such as size, shape and location. By combining these two scanning technologies, a PET-CT scan enables physicians to more accurately diagnose and identify cancer, heart diseases, brain disorders, kidney disorders and many more.

PET CT:

• Positron Emission Tomography (PET) is a type of nuclear medicine procedure that measures metabolic activity of the cells of body tissues
• PET is a combination of nuclear medicine and biochemical analysis. Used mostly in patients with brain or heart conditions and cancer
• PET helps to visualise the biochemical changes taking place in the body, such as the metabolism of the heart muscle
• PET is performed to diagnose neurological conditions such as: Parkinson's, Huntington’s, Epilepsy, Stroke
• To detect the spread of cancer to other parts of the body from the original cancer site
• To detect recurrence of tumors earlier than with other diagnostic modalities

Patient Instructions:

Preparation for scan:

• You have to come as per the time informed to you with 6 hours fasting.
• Do not take any food during those 6 hours , only drink plain water.
• Kindly inform us, if taking any medication and preferably take it 6 hours before appointment time.
• Inform in advance if patient is diabetic & omit the morning dose of insulin or anti diabetic on the day of scan.
• Bring your old files, reports, films and CD with blood report of serum creatinine done within last week.

In the Department:

• You will be provided hospital clothing
• History will be taken and reports will be seen
• After registering, you will go to a preparation area where a PET nurse / technologist will insert a small intravenous into your arm.
• A small amount of radioactive PET medicine will be injected through the IV. This is painless.
• You will be asked to take oral contrast solution before the study.
• You will need to wait upto 60 minutes while the medicine circulates.
• You will then be taken for scan which will take about 15-30 minutes.
• In case of any delay, scans on additional images, if needed, the doctor / technologist will personally explain to you.

After your Scan

• You can resume your normal activities without any restrictions.

What is Gamma Camera/SPECT

SPECT scan is used to analyze the functions of the internal organs. A SPECT scan is a type of nuclear imaging test, which uses a radioactive substance and a special camera to create 2D/3D images. For instance, CT scan can give you information on percentage blockages of different vessels supplying your heart, which a SPECT scan can show how blood flows to your heart.

SPECT SCAN

A single photon emission computed tomography (SPECT) scan is an imaging test that shows how blood flows to tissues and organs. It may be used to help diagnose seizures, stroke, stress fractures, infections, and tumors in the spine.

Cardiology: The functioning of the heart muscle is examined in cardiology - myocardial perfusion imaging (mpi; ischemic heart disease), metabolism of the myocardium. The examination has two parts - before and after physical exercise. The lungs or the venous system can be examined, too.

Neurology:The blood circulation in the brain is examined in neurology. It can localize the afflicted area and help diagnose the disease (dementia, Alzheimer’s disease, Parkinson’s disease). It can also find the exact place where an operation of the brain could be done (epilepsy - double examination - before and during the seizure)

Oncology: SPECT helps with the localization of tumors. It is used during lymphoscintigraphy, examination of the sentinel nodes, etc. Other changes of metabolism Localization of inflammation, injury or joint disease.

1. Low Dose Iodine-131 THERAPY For Hyperthyroidism

FAQs:

What is radioactive iodine?

Radioactive iodine (I-131) has been used to treat overactive thyroid disorders (hyperthyroidism) since the early 1940s. It is an effective method of treatment. It is now being used more often than surgery when definitive (permanent) treatment is needed. Radioactive iodine is taken up by the thyroid gland and destroys its cells. This has the effect of reducing the amount of thyroid hormone made by the thyroid gland and may also reduce the size of the gland.

When is radioactive iodine treatment used?

• As treatment for an overactive thyroid gland, with or without prior antithyroid drug therapy, especially in people with toxic nodular hyperthyroidism
• As treatment for Graves’ disease either because the disease fails to settle after antithyroid medication, or returns after stopping antithyroid medication, or if patients do not tolerate antithyroid medication. It can also be considered early after diagnosis of Graves’ disease should patients wish to have the treatment at this stage

Is it safe to conceive after radioactive iodine treatment?

Following radioactive iodine treatment men should avoid fathering a child for at least six months, and women should avoid conceiving for at least six months. After that time there is no problem with having a baby or with the development of the baby and many people have gone on to conceive and have healthy children following treatment with radioactive iodine.

Who should NOT have radioactive iodine treatment?

Radioactive iodine treatment is not given to:

• Pregnant women - radioiodine crosses the placenta and can affect the thyroid gland developing in the unborn baby
• Breast-feeding women - the radioactive iodine passes via the milk to the baby’s thyroid gland
• Anyone who is regularly vomiting or incontinent
• People with active thyroid eye disease as it may worsen the eye disease unless steroids are given at the same time
• If the thyroid gland is very overactive, radioactive iodine can cause dangerously high levels of thyroid hormone and, very rarely, a condition known as thyroid crisis or storm

Your doctor will therefore prescribe antithyroid drugs to control the thyroid overactivity first before giving you radioactive iodine.

Are there any side effects of treatment with radioactive iodine?

Sometimes the thyroid gland is a bit tender after treatment. This will usually clear up after a few days.

A common longer term side-effect of radioactive iodine treatment is an underactive thyroid gland (hypothyroidism), so it is very important to have regular thyroid blood tests starting from four to six weeks after the treatment to identify and treat this early, with levothyroxine.

If you have existing thyroid eye disease which can occur in Graves’ disease, this may sometimes be aggravated by radioactive iodine treatment (especially in smokers). Make your doctor aware of any eye symptoms you have, to check if these might be thyroid related. Your doctor will advise ways to minimise the risk of worsening eye disease, such as a course of treatment with steroid tablets, early treatment with levothyroxine and stopping smoking. This may require an assessment by an eye specialist.

There is no risk that patients treated with radioactive iodine for an overactive or enlarged thyroid will lose their hair as a result of the treatment.

How is radioactive iodine taken?

Your treatment will take place in hospital but you do not need to be admitted to hospital as an inpatient. The treatment and its effects will be discussed at the hospital before the radioactive iodine is given and you will be asked to give your consent to the treatment. The dose is taken either as a simple capsule swallowed with mouthfuls of water, or as a drink. The gland has to be working when this treatment is taken, so antithyroid tablets should be stopped usually at least one week before the treatment is given. You will be given instructions on when to stop the tablets. You may also be asked to use beta-blockers to relieve any temporary symptoms of hyperthyroidism. Your doctor will discuss with you before treatment whether you should restart the medication afterwards and when.

What safety measures should I take?

After treatment, and depending on the amount of daily contact you have with others, you may be asked to avoid contact with other people for a short time. In particular you should avoid close contact with babies, children under five years and pregnant women. As a general rule you should keep at arm’s length for one week, but the length of time depends on the dose used and the people you will be in contact with.

Recent reports have highlighted the fact that people who have recently had radioactive iodine treatment can trigger radiation detectors used for security purposes, for example at airports and seaports. This can occur for up to four months after treatment. If you are travelling within this time period you should carry a letter from hospital explaining the treatment you have had.

What happens after radioactive iodine treatment?

Follow-up after radioactive iodine treatment is essential. There is no single correct dose and about 10% of patients need a further dose. There are no additional problems associated with having more than one dose. Some patients will still require treatment with antithyroid medication for some weeks or months until the radioactive iodine has been effective and the overactivity has settled.

Over two-thirds of those who have radioactive iodine treatment will develop hypothyroidism (an underactive thyroid). This can occur anytime from one month after the treatment and is most common within the first 12 months after treatment but can occur later. You should have a blood test about four to six weeks after treatment, and should then be checked every one to three months in the first year - usually by hospital clinic. It is very important not to miss these checks even if you feel well, as they can pick up an underactive thyroid before you have symptoms. After that you should see your GP for an annual blood test, or at any time beforehand, if symptoms of hypothyroidism develop. It is usually straightforward to treat an underactive thyroid gland. Levothyroxine, which is thyroxine in tablet form, is used to replace the thyroxine that your thyroid gland is unable to produce.

What about radioactive iodine treatment for children and teenagers?

Radioactive iodine is an effective and safe treatment option for children and teenagers with an overactive thyroid gland, but will usually be given as a second-line treatment after a reasonably long course of antithyroid medication. It is used less commonly in younger children.

2. High Dose Iodine-131 THERAPY For Thyroid Cancer

FAQs:

What is I-131 treatment?

I-131 is a radioactive substance that is taken up by certain type of thyroid cancer cells and destroys these cancerous cells.

It is known to be effective in:

• Certain types of thyroid cancer (Differentiated thyroid cancer)

Any I-131 that is not absorbed by the tumor cells passes out of your body in your sweat, saliva, urine and stool. The I-131 that is trapped in the tumor cells leave the tumor and are passed from your body.

Investigations that will be needed for the treatment

• You need a scan before the treatment known as low dose Iodine scan which you may have had done already.
• You will need tests which your doctor will arrange for you, as follows:
  Blood tests 2 weeks before the treatment

Is there any preparation before the treatment?

Ensure that if you are taking thyroid hormone tablets or any iodine containing preparation this is stopped 4 weeks before treatment.

How is I-131 treatment given?

Before this treatment, you should have as little to eat as possible for at least two hours. The treatment itself involves swallowing either liquid (through a straw) or capsules of radioactive Iodine-131. Additionally, you will be requested not to eat for at least two hours after the therapy, if possible.

What happens after the procedure?

You will remain in hospital in a lead lined private room due to the radiation in your body. During the first 12 hours after the treatment a large amount of the radioactivity passes out of the body through your urine. A scan is performed on the day of discharge in the Nuclear Medicine department. Date of discharged will depend on radiation level inside your body that is measured at regular interval.

Will there be any danger to my family or friends?

Because this type of treatment delivers its radiation within your body and only very small amounts exit your body. As a precaution, during the treatment no visitors are allowed. Following discharge your family and friends are not at risk but we recommend some sensible precautions:

• Always flush the toilet twice after use for one week after the treatment
• Refrain from all contact with young children and pregnant women for one week
• Restrict close contact with other adults for one week
• Avoid sharing a bed with another person for one week

On the day of treatment you will be given specific advice according to your individual circumstances as the advice depends on the amount of treatment your doctor prescribes.

Can I have treatment if I am pregnant or breast-feeding?

No. Women who are pregnant or breast-feeding must not be given treatment. I-131 is radioactive and is not given if you are pregnant. If there are any concerns about pregnancy, a pregnancy test will be done. Reliable birth control should be used until treatment has finished and for at least 6 months afterward. Men are advised not to father a child for the same period. If you are breast-feeding, you should tell your doctor so you can discuss stopping this before you have therapy.

How many treatments will I need?

You will be seen in our clinic after treatment to reassess your health and response to the therapy. The subsequent treatments will depend on clinical assessment.

Are there any side effects?

Possible side effects of treatment are slight nausea, swelling in the neck region and tenderness in your salivary glands.

Possible future health risks from this treatment that an average patient are the development of hypothyroidism (underactive thyroid gland) and a minimal increased risk of cancer induction due to radiation. Additionally, if cancer of the thyroid extensively involves lungs, as a result of this therapeutic procedure, pulmonary fibrosis, pulmonary edema or radiation pneumonitis are possible future health risks to me.

3. Lu-177 DOTATATE THERAPY

FAQs

What is Lu-177 treatment?

Lu-177 is a radioactive substance that we can add to a carrier called DOTATATE. Lutetium-177 is an atom that sends out radioactive particles. Octreotate joins to your neuroendocrine tumor with the radioactive Lutetium atom attached to it. Once in your body, the Lu-177 DOTATATE attaches to specific tumour cells and destroys these cancerous cells.

It is known to be effective in:

• neuroendocrine tumours
• paragangliomas, neuroblastomas
• certain types of thyroid cancer

Any Lu-177 DOTATATE that is not absorbed by the tumor cells passes out of your body in your sweat, saliva, urine and stool. The Lu-177 DOTATATE that is trapped in the tumor cells leave the tumor and are passed from your body.

Investigations that will be needed for the treatment

• You need a scan before the treatment known as octreotide scan or Ga-68 DOTATATE PET/CT which you may have had done already.
• You will need tests which your doctor will arrange for you, as follows:
  • Blood tests 2 weeks before the treatment
  • Blood tests around 2 weeks after the treatment

Is there any preparation before the treatment?

Ensure that if you are taking a depot somatostatin analogue preparation this is stopped 4 weeks before lutetium treatment. You may require subcutaneous octreotide (100mg tds and increase according to symptom control) in the interim.

How is Lu-177 treatment given?

You will be given medicine to prevent nausea. The treatment is given through a drip into your vein over the course of one hour. You will also receive a fluid solution containing amino acids through another drip over four 4 hours to protect your kidneys from the effect of radiation. The Lu-177 DOTATATE will then be given. The Lu-177 DOTATATE takes 60 minutes to infuse.

What happens after the procedure?

You will remain in hospital in a lead lined private room due to the radiation in your body. During the first 12 hours after the treatment a large amount of the radioactivity passes out of the body through your urine. A scan is performed the day after treatment in the Nuclear Medicine department. The majority of patients can be discharged after the single overnight stay.

Will there be any danger to my family or friends?

You will usually be discharging the following morning after treatment because this type of treatment delivers its radiation within your body and only very small amounts exit your body. As a precaution, during the treatment no visitors are allowed. Following discharge your family and friends are not at risk but we recommend some sensible precautions:

• Always flush the toilet twice after use for one week after the treatment
• Refrain from all contact with young children and pregnant women for 3 days
• Restrict close contact with other adults for 3 days
• Avoid sharing a bed with another person for 3 days

On the day of treatment you will be given specific advice according to your individual circumstances as the advice depends on the amount of treatment your doctor prescribes.

Can I have treatment if I am pregnant or breast-feeding?

No. Women who are pregnant or breast-feeding must not be given treatment. Lu-177 DOTATATE is radioactive and is not given if you are pregnant. If there are any concerns about pregnancy, a pregnancy test will be done. Reliable birth control should be used until treatment has finished and for at least 6 months afterward. Men are advised not to father a child for the same period. If you are breast-feeding, you should tell your doctor so you can discuss stopping this before you have therapy.

How many treatments will I need?

Usually 3-6 treatments are given every 8-12 weeks but you will be seen in our clinic after each treatment to reassess your health and response to the therapy. The subsequent treatments will depend upon the effect therapy had on your blood cells, kidney and liver Subsequent clinic assessment (including bloods and scan) are required 2 weeks prior to next treatment cycle.

4. Lu-177 PSMA THERAPY

FAQs

What is Lu-177 treatment?

Lu-177 is a radioactive substance that we can add to a carrier called Prostate specific membrane antigen (PSMA). Lutetium-177 is an atom that sends out radioactive particles. PSMA joins to your prostate tumor with the radioactive Lutetium atom attached to it. Once in your body, the Lu-177 PSMA attaches to specific tumour cells and destroys these cancerous cells.

It is known to be effective in: prostate cancer.

Any Lu-177 PSMA that is not absorbed by the tumor cells passes out of your body in your sweat, saliva, urine and stool. The Lu-177 PSMA that is trapped in the tumor cells leave the tumor and are passed from your body.

Investigations that will be needed for the treatment

• You need a scan before the treatment known as Ga-68 PSMA PET/CT which you may have had done already.
• You will need tests which your doctor will arrange for you, as follows:
  • Blood tests 2 weeks before the treatment
  • Blood tests around 2 weeks weeks after the treatment

Is there any preparation before the treatment?

Ensure that if Taxane-based chemotherapy is paused for at least 4 weeks.

How is Lu-177 treatment given?

You will be given medicine to prevent nausea. The treatment is given through a drip into your vein over the course of one hour. You will also receive normal saline drip and diuretic injection. The Lu-177 PSMA will then be given. The Lu-177 PSMA takes 30-60 minutes to infuse.

What happens after the procedure?

You will remain in hospital in a lead lined private room due to the radiation in your body. During the first 12 hours after the treatment a large amount of the radioactivity passes out of the body through your urine. A scan is performed the day after treatment in the Nuclear Medicine department. The majority of patients can be discharged after the 24-48 hrs overnight stay.

Will there be any danger to my family or friends?

You will usually be discharged within 24-48 hrs after treatment because this type of treatment delivers its radiation within your body and only very small amounts exit your body. As a precaution, during the treatment no visitors are allowed. Following discharge your family and friends are not at risk but we recommend some sensible precautions:

• Always flush the toilet twice after use for one week after the treatment
• Refrain from all contact with young children and pregnant women for 14 days
• Restrict close contact with other adults for 14 days
• Avoid sharing a bed with another person for 14 days

On the day of treatment you will be given specific advice according to your individual circumstances as the advice depends on the amount of treatment your doctor prescribes.

How many treatments will I need?

Usually 3-5 treatments are given every 8-12 weeks but you will be seen in our clinic after each treatment to reassess your health and response to the therapy. The subsequent treatments will depend upon the effect therapy had on your blood cells (including PSA), kidney and liver. Subsequent clinic assessment (including bloods and scan) are required 2 weeks prior to next treatment cycle.

Are there any side effects?

The most reported side effect is nausea but we will give you an injection before the treatment to prevent this and we will give you tablets to take home.

Other reported side effects are:

• Temporary reduction in your blood count and white cells
• A reduction in salivary gland function
• A reduction in kidney function
• Tiredness