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 an 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. The most common sites are the lungs, pancreas, appendix, small intestine, and rectum.
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. Common cancer symptoms such as fatigue, weight loss, and loss of appetite may be experienced if you have a neuroendocrine tumour (NET).
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 signs and symptoms are usually more specific according to the type of NET.
How Are Neuroendocrine Tumours (NETs) Diagnosed?
When diagnosing neuroendocrine tumours, our doctors may order several tests to help them understand your symptoms.
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 help doctors 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 diagnosing neuroendocrine tumours is nuclear medicine imaging tests. We have mentioned octreotide scintigraphy (using a radioactive medium). Others may include PET-Gallium68 octreotide imaging (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.
Iodine 123/131 MIBG Scans:
Iodine 123/131 MIBG Scans are usually used for neuroendocrine tumours of the paraganglionic type and pheochromocytoma.
Other Imaging Studies:
Other diagnostic means used are endoscopy, ultrasound, computed tomography, and magnetic resonance imaging (MRI).
What Are Some of the Treatment Options & Side Effects of Treatment 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.
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.
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. 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.
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.
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 are fatigue, nausea accompanied by vomiting, hair loss, loss of appetite, and diarrhoea.
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.
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.
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.
The most common side effects of this type of therapy are nausea and vomiting, generalised fatigue, potential renal impairment, and marrow suppression.
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. It is typically used to target lesions that might be causing symptoms.
Side effects depend on the site of radiotherapy and will usually include skin dryness and redness in the treated area.
TREATMENT TARGETING THE LIVER
Treatment targeting the liver can be used for individuals where the NETs have metastasised to the liver. Some examples of targeted treatment include;
Radiofrequency ablation (RFA). This involves inserting a probe into the lesion, which is subsequently destroyed typically by radiofrequency or microwave ablation.
Chemoembilisation. This treatment involves injecting small particles with a chemotherapy agent into the liver artery and blocking the blood supply to the tumour with the effects of chemotherapy.
Radioemboilisation. This involves injecting small radioactive particles directly into the liver artery, which causes radioactive damage to the tumours.
Coping With Neuroendocrine Tumours (NETs) & Seeking Support
Being diagnosed with neuroendocrine tumours (NETs) can be overwhelming and stressful. Patients should find ways to cope with these feelings and seek support where possible.
Learn about your diagnosis to help you understand and process what you are going through. Speak to our doctors and medical team should you have any questions about your treatment options and prognosis. This information can allow you to feel more confident in making the decisions you need to make during this period.
Lean on loved ones for support, and do not be afraid to ask for help. Your family and friends can provide a healthy outlet for you to process and deal with your feelings. Let them know how they can help you out during this time, whether it is accompanying you to doctors appointments or helping you run errands.
Coping & Support
Being diagnosed with a neuroendocrine tumour can be a stressful and overwhelming period. Over time, patients will find methods to cope. Until then, you may find it helpful to:
- Learn as much as you can about your diagnosis, allowing you to make decisions about your care and treatment. Ask your doctor about your neuroendocrine tumour, including the available treatment options. As you gain a better understanding of the type of neuroendocrine tumour you have, you may become more confident in making decisions regarding your treatment. This can help you to feel more in control of the situation.
- Lean on your family and friends for support. While it can be difficult to address your diagnosis, talking about it allows you to share the load with those who love you. Additionally, verbalising your situation can help you think through your decisions regarding your treatment.
- Connect with others with neuroendocrine tumours. Joining a support group can help you feel less alone. Support groups are also a safe space for you to voice your experience with others experiencing a similar diagnosis.
What Are Some Recommended Changes to My Diet if I Have Neuroendocrine Tumours (NETs)?
Diet & NETs
Eating a balanced diet is essential. However, neuroendocrine tumours (NETs) and their treatment options can result in diet problems. To ease this issue, speak to your dietitian and medical team about any dietary issues that you are facing during treatment. They will be able to give you medication and tips to help you cope with the side effects of neuroendocrine tumours.
Common Diet Issues
There are many different types of NETs, and each type may have a different effect on your diet and appetite.
Diarrhoea is defined as having more than 3 watery or liquid stools within 24 hours. This can be severe, especially if you suffer from carcinoid syndrome, a group of symptoms that happen when a neuroendocrine tumour produces large amounts of hormones.
During bouts of diarrhoea, you lose a lot of fluid as a result. Therefore, it is important to drink small sips of water frequently throughout the day.
Unfortunately, a high-fibre diet can worsen diarrhoea. You should instead stick to foods such as:
- White rice, pasta, and bread
- Well-cooked eggs
Weight Loss & Loss of Appetite
If you have been diagnosed with neuroendocrine tumours, you may find that you are losing weight even if you are eating normally. Your body may not be effectively absorbing the nutrients from your food. Alternatively, you may be burning calories quicker than normal.
To keep your body’s weight up, you can try:
- Eating smaller meals and snacks every 2 to 3 hours
- Opting for foods that contain proteins such as meat or meat alternatives (tofu and soya), eggs, beans, or legumes
- Using whole milk and butter
- Drinking high-calorie drinks such as full-fat milk or smoothies
Feeling or Being Sick
To help with sickness, try:
- Eating several small meals and snacks as opposed to 3 large meals
- Eating light such as plain toast and crackers
- Avoiding greasy and fatty foods
Difficulty Absorbing Fat (Fat Malabsorption)
Carcinoid syndrome refers to a group of symptoms that can happen when NETs produce excessive amounts of hormones. The most common symptoms of carcinoid syndrome are flushing of the skin, diarrhoea and tummy (abdominal) pain.
For some patients, certain foods and drinks can trigger the symptoms of carcinoid syndrome. Some common triggers are having a large meal and eating fatty or spicy foods. Additionally, foods and beverages containing high levels of amines can also trigger diarrhoea and flushing of the skin. These include:
- Aged cheese
- Alcohol and fermented beverages
- Smoked and salted fish and meats
- Soybean products
Where Can I Find Support in Singapore if I Have Neuroendocrine Tumours (NETs)?
If you have been diagnosed with neuroendocrine tumours and are looking for support groups in Singapore, here are two options that you may want to consider:
How Can I Help Support a Loved One With Neuroendocrine Tumours (NETs)?
If you are the primary caregiver for someone who has been diagnosed with neuroendocrine tumours, you may be wondering how you can better care for your loved one.
Understanding the Caregiver Role
As a caregiver, you provide support in various forms. This may include day-to-day activities, medical needs, helping them make important decisions, and tending to their emotional needs.
The role of a caregiver takes many forms. Understanding what is required of you can better prepare you to carry out your responsibilities in helping your loved one. The extent of help that your loved one needs may vary depending on their stage of diagnosis, age, and overall health.
There are 5 broad categories of what is needed from a caregiver. They are:
- Physical needs, which includes aiding with daily activities.
- Health and medical needs; where you ensure that the patient is taking medicine and attending their medical appointments.
- Emotional needs; in which you show your love and support.
- Spiritual needs; where you are there to help them continue their religious practices and beliefs.
- Financial and legal needs; where you aid them in managing their insurance and assets when they cannot do so and planning for their future.
Caregiving Is a Team Effort
It is important to talk to your loved ones and include them in the planning and decision-making process if the patient is comfortable with this. It helps to be able to share the load amongst different caregivers.
For instance, one family member or friend could be handling financial affairs and another providing daily care. Sharing the load can make it easier for you to take care of your loved one.
Taking on the role of a caregiver can come with its own set of stresses and uncertainties. It is important to recognise your own needs and capabilities. This will help you avoid caregiver burnout. Remember, you cannot care for your loved one if you are unwell or burnt out.