Pancreatic Neuroendocrine Tumours (pNETs)
Pancreatic neuroendocrine tumours are tumours that develop in the endocrine cells (hormone-producing cells) of the pancreas. Also known as pNETS or islet cell tumours, these growths can often be hard to diagnose as they exhibit symptoms similar to less serious illnesses.
The tumours actively secreting hormones are known as functioning pNETs; whereas those not secreting hormones are non-functioning. The functioning pNETS accounts for about 30-40% of all pNETs.
There are various types of pancreatic neuroendocrine tumours known today, depending on the exact cell that is affected. For instance, if the insulin-producing endocrine cells are affected, this pNET type is known as insulinoma. Some other such types include glucagonoma, gastrinoma, somatostatinoma, and VIPomas.
Symptoms:
Since functioning pNETs are actively producing hormones, the patients with functioning pNETs will usually present earlier for medical attention due to their symptoms.
The non-functioning pNETS are commonly identified incidentally from imaging performed for unrelated conditions. The presentation also depends on the tumour location; those located at the head of the pancreas will present earlier with jaundice when they compress the bile duct, and those situated in the body and tail of the pancreas will present later when the tumours are larger and at a more advanced stage.
Some common symptoms of functioning pNETs include nausea, diarrhoea, stomach ulcers, and anaemia. The more specific symptoms of the specific pNETs are as the followings:
For gastrinoma, symptoms include:
- Ulcers and associated symptoms (pain, nausea, loss of appetite, blood in stool)
- Anemia and associated symptoms (fatigue, shortness of breath)
- Diarrhea
- Unexpected/unintentional weight loss
For glucagonoma, symptoms include:
- Feeling extremely thirsty or hungry
- Frequent urination
- Diarrhea
- Unintended weight loss
For insulinoma, symptoms include:
- Weakness
- Confusion
- Sweating
- Intense hunger
- Fast and rapid heartbeat
- Seizures
- Loss of consciousness
- Coma
For somatostatinoma, symptoms include:
- Stomach pain
- Nausea
- Loss of appetite
- Unintended weight loss
- Diarrhea
- Diabetes
- Jaundice
For VIPoma, symptoms include:
- Diarrhea that gets more frequent, watery and worse over time
- Nausea
- Vomiting
- Muscle cramps
- Fatigue
- Flushing (when your face and neck become flushed, red and feel warm)
Treatment:
The treatment of pNETs depends on their functionality. Functioning pNETs can be completely treated with surgical resection if they have not metastasised. However, the treatment of non-functioning pNETs depends on the size and aggressiveness of the tumour (the grade and differentiation).
The treatment options depend on the function and stage of the tumour, e.g.
- Surgery (Whipples or distal pancreatectomy. Open, laparoscopic or robotic approach depending on suitability)
- Hormone therapy
- Chemotherapy
- Peptide Receptor Radionuclide Therapy
- Targeted therapy
