Yttrium-90 Selective Internal Radiation FAQ, Sirt FAQ, Liver Cancer, Liver Cancer Treatment Singapore, Theranostics

What Is Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

Yttrium-90 Selective Internal Radiation Therapy (SIRT) is known as radioembolisation, and its purpose is to eliminate tumours located in the liver. It involves the injection of small radioactive particles directly into the liver artery. These beads emit short-range radiation, which targets the tumour but minimises damage to the surrounding tissues.

How Effective Is Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

The effect of radioembolisation depends on several factors, including the disease burden underlying liver function and the technique used for dosimetric evaluation. Overall, studies have demonstrated improvements in disease-free progression, reduction in symptoms and improvements in overall survival. 

What Are the Side Effects of Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

In approximately one-third of patients, SIRT administration causes immediate short-term abdominal pain, requiring narcotic analgesia, and is typically self-limiting.

Post-SIRT in the treatment of liver cancer therapy sees lethargy and nausea are common symptoms and can last up to two weeks and may require medication. Most patients develop a mild to a moderate fever that may last for several days following SIRT administration. This fever does not usually require treatment.

The most common and potentially severe complications of SIRT result from either: 

  • Inadvertent administration of SIR-Spheres into the gastrointestinal tract resulting in gastritis/duodenitis
  • Radiation-induced liver disease resulting from a radiation overdose to the normal liver parenchyma

The incidence of gastritis/duodenitis can be reduced by careful attention to the administration procedure to ensure a minimal chance of SIR-Spheres entering the numerous small arteries supplying the gastrointestinal tract.

Radiation-induced liver disease is largely, but not entirely, preventable by using appropriate SIRT doses and making allowances for dose reduction when there is an increased risk of causing radiation damage. Such cases include patients with pre-existing liver damage, poor liver reserve or small volume tumour mass in the liver. 

The reported incidence of gastritis/duodenitis is less than 10%, while the reported rate of radiation-induced liver disease is less than 1%.

The incidence of Radiation Pneumonitis (inflammation of the lungs due to radiation) is expected to be low where appropriate pre-therapy workup and dose reductions are followed. The risk of radiation pneumonitis nevertheless exists and has been reported.

Does Yttrium-90 Selective Internal Radiation Therapy (SIRT) Extend Your Life Expectancy?

While outcomes following radioembolisation depend on various clinical and technical factors, some studies show improvements in progression-free survival, symptoms and overall survival. 

How Many Yttrium-90 Selective Internal Radiation Therapy (SIRT) Treatments Can You Have?

Typically most patients will undergo a single treatment with radioembolisation, but repeated treatments can be done, depending on the clinical needs. 

What Happens After Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

After treatment, the patient will be transferred to a recovery area where they will remain for approximately 1 to 4 hours. During this period, the catheter is removed from the bladder. 

Yttrium-90 Selective Internal Radiation Therapy (SIRT) treatment has several reported side effects. These include: 

  • A fever of more than 38 ° C
  • Abdominal pain
  • Nausea and vomiting

Our specialist will indicate if antipyretic, analgesic and antiemetic medications are necessary.

Click here for more information on Yttrium-90 Selective Internal Radiation Therapy (SIRT) and the treatment of liver cancer through theranostics.

Yttrium-90 Selective Internal Radiation Therapy, SIRT, Theranostics, Theranostics Singapore, Cancer Treatment, Liver Cancer, Dr Andrew Tan

What Is Yttrium-90 Selective Internal Radiation Therapy (SIRT)

Yttrium-90 Selective Internal Radiation Therapy (SIRT) is known as radioembolisation, and its purpose is to eliminate tumours located in the liver. It works as small radioactive beads that migrate to the tumour through one’s arteries. These beads emit short-range radiation, which targets the tumour but minimises damage to the surrounding tissues.

What Is Liver Cancer?

Liver (Hepatic) cancer occurs when there is an abnormal and uncontrolled growth of liver cells. Although there are many different types, the most common is hepatocellular carcinoma.

Various risk factors can lead to this type of cancer. Among them, we have episodes of hepatitis, liver cirrhosis, excessive alcohol consumption, obesity, and diabetes, among others.

Typically, there is pain in the right abdominal region and yellowing of the skin (pathological jaundice). Although it is usually asymptomatic at the beginning, it tends to generate symptoms after the disease has advanced significantly.

What Is A Mapping Arteriogram Procedure / Liver Lung Shunt Study & Why Do I Need It?

Mapping Arteriogram Procedure / Liver Lung shunt study must be performed a week before starting the SIRT treatment. Mapping will allow the identification of the blood vessels (arteries) that are directed to the tumour, as well as blocking the  passage to other organs such as the intestines. This is necessary to prevent the radiation from affecting healthy organs.

The procedure requires a series of preparations and steps before, during, and after. Everything related to mapping arteriography will be explained in detail by your treating physician.

What to Expect Before Treatment With Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

Aside from the angiography, there will be a series of blood tests to assess the baseline liver, kidney and bone marrow function. 

The patient is required to fast for 6 hours before the angiogram, and there will be a clinical examination prior to the procedure. 

The angiogram will be performed with a liver lung shunt study. This involves injecting a diagnostic radiotracer into the hepatic artery catheters, which will allow the doctors to fully understand the distribution of particles into the tumour and normal tissue. The doctors will then be able to determine if the patient is a suitable candidate for Y90 SIRT and, if so, to calculate a proper dose of the radioactive microspheres.

  • Speak to Our Doctor About Other Prescribed Medications

A series of medications will most likely need to be discontinued on the day of treatment to ensure successful therapy and even mapping, so make a list of your medications and consult with our doctor.

Among them, we have anticoagulants – such as aspirin, AINES, vitamin E, oral hypoglycemic agents, and insulin – and diuretics, among others. In the case of diabetes treatment, your dose may be adjusted.

  • Reactions to Contrast 

These types of procedures generally make use of contrast media, allowing the doctor to see the arteries that communicate with the tumour. If you have previously had allergic reactions to contrast media, you should notify your medical care team to avoid complications. This will allow our doctor to look for an alternative to be used as a contrast medium.

What to Expect During Treatment With Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

The actual Y90 SIRT procedure is almost entirely like the pre-treatment angiographic mapping and liver lung shunt. The only difference is the radioactive particles used. While in the assessment phase, a diagnostic tracer is used, in the treatment phase, the Y90 microspheres are injected.

How Long Does Treatment With Yttrium-90 Selective Internal Radiation Therapy (SIRT) Take?

The angiographic procedure and implantation of the microspheres depend on the complexity of the patient. Usually, the procedure will take about 90 minutes.

What to Expect After Treatment With Yttrium-90 Selective Internal Radiation Therapy (SIRT)?

After treatment, the patient will be transferred to a recovery area where they will remain for approximately 1 to 4 hours. During this period, the catheter is removed from the bladder. 

Yttrium-90 Selective Internal Radiation Therapy (SIRT) treatment has several reported side effects. These include: 

  • A fever of more than 38 ° C
  • Abdominal pain
  • Nausea and vomiting

Our specialist will indicate if antipyretic, analgesic and antiemetic medications are necessary.

How Long Before I Can Be Discharged After Treatment With Yttrium-90 Selective Internal Radiation Therapy (SIRT)? 

You are typically required to rest in bed for a minimum of 6 hours post-treatment. If everything goes well with no complications, you should be able to be discharged the next morning.

You Should Arrange For Someone to Take You Home Following Treatment With Yttrium-90 Selective Internal Radiation Therapy (SIRT)

As it is a radiation treatment that causes fatigue in patients, our doctor will recommend that someone take care of bringing you home safely. You should arrange for an accompanying adult after your treatment. 

What Questions Should I Ask My Doctor?

It is normal to experience fear or doubts when diagnosed with liver cancer, so we have prepared a shortlist of questions that you can ask your doctor. 

  • How do I know if I am a candidate for Selective Internal Radiation Therapy (SIRT)?
  • Is it mandatory to perform mapping arteriography before starting SRIT?
  • Should I stop my medication if I am diabetic?
  • What if I am allergic to contrast and am not aware?
  • If I have a device on my skin, what should I do?
  • Can I have sex?
  • What to do with my clothes in case they get stained with body fluids?
  • Is it mandatory to have a companion when I go home?
  • If I follow another treatment such as chemotherapy, should I stop it?

In case of not feeling well, you should notify your companion of your discomfort. Your companion should inform your treating physician. Side effects after therapy are generally few and short-lived.

It is essential that if your companion notices something out of the ordinary after the treatment, they should immediately notify your doctor so that they can carry out the corresponding corrections.

Neuroendocrine Tumours, NETs, Cancer Treatment, Theranostics, Theranostics Singapore, Dr Andrew Tan

What Are Neuroendocrine Tumours (NETs)?

Neuroendocrine Tumours (NETs) are rare tumours that affect specialised cells known as neuroendocrine cells.

The peculiarity of this type of cell resides in that they have traits similar to nerve cells and hormone-producing cells. Neuroendocrine cells are found in all organs of the individual and help control many of their functions.

A tumour can take years to appear. However, others grow rapidly and appear anywhere in the body. Still, the most common sites are the lungs, pancreas, appendix, small intestine, and rectum.

Where Are Neuroendocrine Tumours (NETs) Typically Found?

As mentioned, neuroendocrine tumours can appear in any part of the human body. Although it has a preference for some regions, these include: 

  • Gastrointestinal Tract: This is one of the main areas affected by this type of tumour, the large intestine taking 20% ​​of appearances, the small intestine 19%, and the appendix 4%. These types of tumours used to be called carcinoids.
  • Lung: Approximately 30% of NETs occur in the bronchial system, making it the second most common area of the body for neuroendocrine tumours. They were also formerly known as carcinoid tumours.
  • Pancreas: The pancreas takes 7% of appearances, formerly known as islet cell tumours. These are classified according to the endocrine cell from which they derive as gastrinoma, insulinoma, glucagonoma, among others.
  • In some cases, the primary organ cannot be found (15%). In some cases, it can affect the adrenal glands, such as the thyroid.

What Causes Neuroendocrine Tumours (NETs)?

Although they are rare, neuroendocrine tumours have an incidence of 10 cases per 100,000 inhabitants – and thanks to better diagnostic techniques – it is possible to study this disease statistically.

In general, neuroendocrine tumours are slow-growing ones, but the direct cause that triggers the disease is still unknown.

However, it is known that these tumours begin when neuroendocrine cells develop changes – in other words: mutations – in their DNA, which trigger structural changes.

There are risk factors that can contribute to developing cancer, although they are not the direct cause. It appears more often in adults than in children.

Additionally, hereditary syndromes are another risk factor, and among them, we have multiple endocrine neoplasia types 1 and 2, Von Hippel-Lindau syndrome, neurofibromatosis type-1, and complex tuberous sclerosis.

What Are the Symptoms of Neuroendocrine Tumours (NETs)?

NETs are, in general, asymptomatic in their initial stages. So their discovery is usually fortuitous unless it generates symptoms or pain according to the location that occurs. Common symptoms of cancer such as fatigue, weight loss, and loss of appetite may be experienced. 

The symptoms of the neuroendocrine tumour – if it is localised – are manifested by recurrent pain in the area, reddish, thickened skin, nausea, vomiting, cough or hoarseness, changes in bowel habits, jaundice, unusual bleeding.

Hyperglycemia/hypoglycemia, diarrhoea, skin rash, facial flushing, confusion, anxiety, ulcer disease, dizziness, tremors are other symptoms that an individual may experience. Some symptoms are usually more specific according to the type of NET that is possessed.

How Are Neuroendocrine Tumours (NETs) Diagnosed?

Initial Blood Study & Urinalysis:

Our doctor may request a 24-hour urine test to reveal a serotonin breakdown product (5-HIAA or 5-hydroxy indole acetic acid). Doctors may also order a blood test to measure fasting serum Chromogranin A levels.


When a tumour is localised, a tissue biopsy is performed to determine the presence of cancer cells, staging the cancer, and guide the patient’s treatment.

Nuclear Medicine Imaging Tests:

One of the most accurate methods for the diagnosis of neuroendocrine tumours is nuclear medicine imaging tests. We have mentioned octreotide scintigraphy and positron emission tomography (using a radioactive medium). Others may include PET-Gallium68 (currently the most sensitive test to identify NETs), whose objective is to detect the expression of somatostatin receptors. Another diagnostic method is the PET-FDG (glucose) that detects tumour activity through the consumption of glucose. 

MIBG 131 Scan:

The MBIG 131 Scan is usually used for neuroendocrine tumours of the paraganglionic type and pheochromocytoma.

Other Imaging Studies:

Other diagnostic means that may be used are endoscopy, ultrasound, computed tomography, and magnetic resonance imaging (MRI);

What Are the Treatment Options Available for Neuroendocrine Tumours (NETs)?

Before starting any treatment of neuroendocrine tumours, our doctor must stage or classify the grade of the cancer to find a suitable treatment plan; this is done through imaging studies, laboratory tests, and monitoring the patient’s symptoms.

1) Active Surveillance

Active surveillance is one of the most conservative treatments and is recommended in cases of slow-growing neuroendocrine tumours that do not present symptoms. The therapeutic approach begins after the first symptoms or in the event of a tumour enlargement.

If the patient neglects their routine check-ups, they may risk excessive tumour growth or metastasis.

2) Surgery

Surgery is the standard recommended treatment for neuroendocrine tumours. It consists of the extraction of the tumour that is often localised, together with the respective margin surrounding tissue to avoid the risk of metastasis.

If the entire tumour cannot be removed, debulking is carried out. This is where a part of the tumour is removed to reduce its size.

However, any procedure runs the risk of side effects. This may include:  

  • General risks of anaesthesia
  • General surgical associated risks
  • Carcinoid crisis (treated with a somatostatin analogue) Symptoms of a carcinoid crisis are reddening of the skin, facial lesions, diarrhoea, shortness of breath, and a fast heartbeat.

3) Somatostatin Analogues

These are drugs that have an action similar to the hormone somatostatin. These analogues manage the symptoms caused by NETs. They also slow their growth, although they do not reduce their size.

There are multiple types of somatostatin analogues available, and they are usually divided into the length of action. The long-acting octreotide (Sandostatin) administered intramuscularly can last for months, while medium and short-acting versions mandate an effect of weeks or days. 

The potential side effects of this treatment include hyperglycemia, gallstones, abdominal distention, nausea, sometimes accompanied by vomiting.

4) Chemotherapy

One drug or a combination of several drugs can be used in patients with neuroendocrine tumours. This treatment is typically used in cases where the disease is metastatic. 

Side effects depend on the chemotherapy cycles that the patient undergoes, the type of medications used, the stage of the NETs. The usual symptoms that may occur are fatigue, nausea accompanied by vomiting, hair loss, loss of appetite, and diarrhoea.

5) Targeted Therapy

This type of treatment limits the damage to healthy cells by blocking the growth and spread of cancer cells. This is achieved through tumour genes and proteins.

Among the targeted therapies is Everolimus (Afinitor), which targets gastrointestinal NETs, pancreas, and lungs, reducing accelerated tumour growth. This therapy acts on a molecule called mTOR present in tumour cells that facilitates their survival.

Another targeted therapy is Sunitinib (Sutent), and it targets a protein called VEGF. This protein is essential in the formation of blood vessels that nourish the tumour. Therefore, by attacking these proteins, nutrients are being removed from the tumour, preventing its growth. This therapy is helpful in the treatment of pancreatic NETs.

The side effects for Everolimus are fatigue, mouth lesions, alteration in the blood formula count. For Sunitinib, the side effects range from tiredness, diarrhoea, nausea accompanied by vomiting, and increased blood pressure.

6) Immunotherapy

Immunotherapy works to improve the patient’s immune system. The drug interferon alfa-2b (Intron A) may be used to treat NETs. It functions to reduce some symptoms of the disease, such as diarrhoea and skin redness.

Immunotherapy may often be used in combination with other treatment forms. 

Possible side effects range from fatigue, fever, nausea, vomiting, diarrhoea, skin rashes, and rarely, difficulty breathing.

7) Peptide Receptor Radionuclide Therapy (PRRT)

In 2018, the FDA approved treatment with 177 Lu-dotatate (Lutathera), aimed at gastrointestinal and pancreatic NETs. It binds to the somatostatin in the tumour through a receptor and sends out radioactive particles that kill cancer cells.

This type of therapy’s most common side effects are low potassium, low white blood cell levels, hyperglycemia, vomiting preceded by nausea, and fatigue.

8) Radiotherapy

The type of radiation therapy used for this pathology is an external beam, which directs the X-ray to a precise point on the individual’s body. Its use is to relieve pain caused by NET.

Patients may experience a dry cough, sore throat (when radiation therapy is aimed at the neck), dryness in the treated area, and skin redness. The most common side effects are nausea, vomiting, and tiredness. Difficulty breathing, while rare, is another side effect that patients may experience.

9) Treatment Targeting the Liver

Treatment targeting the liver is recommended for individuals where the NETs have metastasised to the liver. The first type of this treatment is radiofrequency ablation (RFA), which destroys the tumour by electrical heating. This works if the tumour is small.

The second form of treatment is the embolisation of the hepatic artery, which consists of blocking the blood flow to the tumour. 

There are three methods of doing this: soft embolisation (not combined), chemoembolisation (combined with chemotherapy), radioembolisation (combined with radiation therapy). The latter uses a radioactive material called Yttrium-90.

Side effects include pain in the abdomen at the level of the liver, fever, and increased liver profile after two days after treatment. However, these side effects tend to disappear quickly.

Who Will Benefit From Treatment With Lutetium-177 Octreotate Therapy?

The individuals who may benefit from this type of therapy are typically those with metastatic NETs with a high uptake of the octreotide tracer, demonstrated on imaging. 

What Are Some Questions I Should Be Asking My Doctor When Considering Treatment Options for Neuroendocrine Tumours (NETs)?

Here are some questions that you can ask your doctor regarding the treatment therapy that you will receive.

  • How many treatment options do I have?
  • Is it possible to combine treatment options?
  • What is the effectiveness rate of the treatment that I will receive?
  • What is the goal of my treatment? Relieve the pain? Heal my condition?
  • If the surgery fails, do I have other treatment options?
  • What do I do if the side effects of my treatment persist?
  • Is there treatment for the side effects I may experience?
  • How will the treatment I receive affect my life and current routine?
  • Will the treatment affect my sex life?
  • Will I still be able to conceive children after the treatment?

These are just some questions to ask your doctor before starting treatment.