Neuroendocrine Neoplasms: A riddle wrapped in a mystery inside an enigma
The riddle.For many years, I've been reading and blogging about Neuroendocrine Neoplasms, NENs for short. NEN is a relatively new term which came after my diagnosis. Nomenclature is still evolving and there is always something to learn. It's also true to say the term 'Neuroendocrine Neoplasms' is the same as saying 'Neuroendocrine Cancer'. These neoplasms are cancers that begin in specialised cells called 'neuroendocrine cells'. Neuroendocrine cells have traits similar to those of nerve cells and hormone-producing cells, particularly the latter. In face one NET specialist said "While the name “neuroendocrine” implies that these tumors involve both nerve cells and…
Somatostatin Analogues for Neuroendocrine Cancer: Lanreotide and Octreotide
Updated and reviewed 15th January 2025. Somatostatin Analogues are the 'workhorse' treatments for those living with NETs, particularly where certain syndromes are involved. So not just for classic NETs with Carcinoid Syndrome but also for treating the hormone overscretions caused by insulinoma, gastrinoma, glucagonoma and VIPoma (all types of pNETs) and others. They are most effective if the NETs express somatostatin receptors. They also have an anti-tumour effect but more of a slowing down of growth rather than a killing or reduction of tumour size - but there are always outliers where such effects are displayed.Somatostatin is actually a naturally occurring hormone produced by the…
Neuroendocrine Cancer – tumour markers and hormone levels
Originally published 2016, updated October 2025BackgroundSome people hear the terms "tumour markers" and "hormone levels" when they are diagnosed with Neuroendocrine Neoplasms (NENs). That might be confusing or even alarming at the time. Most people diagnosed with cancer will have had a form of medical testing at some point in their life, i.e. the sampling and testing of blood, urine, saliva, stool or body tissue. With NENs, the medical staff are just measuring the content of a 'substance' and then taking a view whether this is normal or not based on pre-determined ranges. These tests are normally done as a…
Weight – the NET Effect
ForewordAfter my first surgery in November 2010, I came out at the lightest weight I had been for many many years (10st 7lbs (147lbs)). 6-7 weeks later I went back to work and people privately commented that I shouldn't be at work, I looked too frail and ill. Perhaps it was because my suit no longer fitted me properly! That was an expensive year because I had to buy new suits, a requirement of my employment.Fast forward 4 years, I had to buy some more suits as my weight was going back on.Fast forward 14 years and my weight is…
Neuroendocrine Cancer – the diarrhea jigsaw
Reviewed and updated 5th July 2024Diarrhea can be a symptom of many conditions, but it is particularly key in Neuroendocrine Tumour (NET) Syndromes and types, in particular, so called Carcinoid Syndrome but also in those associated with various other NET types such as VIPoma, PPoma, Gastrinoma, Somatostatinoma, Medullary Thyroid Carcinoma.Secondly, it can be a key consequence (side effect) of the treatment for Neuroendocrine Tumours and Carcinomas, in particular following surgery where various bits of the gastrointestinal tract are excised to remove and/or debulk tumour load.There are other reasons that might be causing or contributing, including (but not limited to) endocrine…
The Syndromes of Neuroendocrine Cancer – Early Signs of a Late Diagnosis
Updated 14th June 2024 The Syndromes of Neuroendocrine Cancer - Early Signs of a Late Diagnosis There are some curious things about Neuroendocrine Cancer (NETs elsewhere in the text on the basis that a hormonal syndrome is extremely rare in Neuroendocrine Carcinoma (NEC)). One of them is that it can very often exhibit one or more vague symptoms collectively known as a 'syndrome'. Syndrome is an apt word to describe these complications as the most general meaning in medical terms is a group of symptoms that together are characteristic of a specific disorder or disease". Having a syndrome can often…
Histamine – NET or NOT?
Histamine is mentioned a lot in both patient groups and in literature as somehow connected with NETs, particularly with so called carcinoid syndrome (CS). In fact, various putative mediators, including serotonin, catecholamines, brady- and tachykinins, kallikrein, histamine, motilin, and prostaglandins, have been suggested as potential causative factors for the symptoms and complications associated with CS. It is generally believed that most of these tumour-derived secretory products are inactivated by hepatocytes and, therefore, only cause symptoms when they either bypass or are secreted outside of the portal vein drainage system. I wanted to focus on Histamine in this article. But what…
Neuroendocrine Cancer – Clinical Esoterica
The good news ....... things are improving, the latest US figures confirm two major changes:1. Most diagnoses are now early stage2. The disease is no longer rare and no longer an orphan diseaseOne of the key awareness messages for Neuroendocrine Cancer is the hormonal syndromes that can often accompany the diagnosis for many people. As it's a difficult disease to diagnose, many people struggle with these syndromes for some time before formal diagnosis of Neuroendocrine Cancer. Some continue to struggle after.Neuroendocrine Cancer can often be uncannily quiet, but the tumours can be 'functional' and over-secrete certain hormones to add or…
European Neuroendocrine Tumor Society (ENETS) 2023 guidance paper for Duodenal neuroendocrine tumours (NETs) G1–G3
The ENETS 2023 guideline for dNETs are combined with the guidelines for Gastric NET (gNET) due to their close relationship in anatomical terms. But there are functional linkages to the pancreas, therefore also links to that as above. The duodenum is technically part of the small intestine, and you can find that in most anatomy-based descriptions. One of the research references I used was titled “Somewhere between the pancreas and the small intestine” and in the case of Duodenal NENs (dNENs), I can understand why they adopted that unconventional anatomy description. I suspect they contextually meant that they are not…
European Neuroendocrine Tumor Society 2023 guidance paper for functioning pancreatic neuroendocrine tumour syndromes
There is very much a multi-disciplinary team (MDT) approach to treating Neuroendocrine Tumours (NET) in Europe and many other places. In Europe and the extra-Europe CoEs in Australia, Israel and the USA, this is centred on the establishment of the Centre of Excellence programme that has been running since 2009. But underneath that are some excellent MDTs not yet accredited who may still utilise ENETs guidelines to treat and manage their patients. This 2023 guideline paper sets the scene for an important and complex group of tumours - pancreatic NETs. It's well known and accepted that the minority of pancreatic NETs…
A spotlight on duodenal Neuroendocrine Neoplasms (dNENs)
What are Duodenal Neuroendocrine Neoplasms (dNEN)? The duodenum is technically part of the small intestine, and you can find that in most anatomy-based descriptions. One of the research references I used was titled "Somewhere between the pancreas and the small intestine" and in the case of Duodenal NENs (dNENs), I can understand why they adopted that unconventional anatomy description. I suspect they contextually meant that they are not like either of these organs, but they share some similarities. They are not normally treated like small intestine NETs (SI NETs) or pancreatic NETs (pNETs) but they share some relationships, particularly…
The NET Detectives
The NET Detectives is an awareness post.Detecting NETsIn general, it's probably true to say that Neuroendocrine Tumours (NETs) are difficult to diagnose. Some are more complex than others and their heterogeneity is legendary. In many cases, they can be quiet, and imaging is key in finding them if they are big enough to be seen. As most primary care facilities (e.g. General Practitioner (GP) offices) don't have a range of imaging devices on site, referrals are often necessary to investigate more. I don't believe it's right to say this referral is a misdiagnosis, it's just another stage in the investigation,…
A spotlight on Gastric Neuroendocrine Neoplasms
What are Gastric NENsUnlike other anatomical types, the word Gastric is used to indicate a tumour (NET) or carcinoma (NEC) in the stomach. The stomach lies at the bottom of your oesophagus and connects to the first part of the small intestine (the duodenum). Clearly a key part of the gastrointestinal system, it processes food on its journey downwards.The stomach produces strong acid. This kills many microorganisms that might have been swallowed along with the food. It also contains special chemicals called enzymes. These are important for breaking down the food so it can be absorbed by the body. After…
Proton Pump Inhibitors (…..and H2 Blockers) the NET Effect
What are Proton pump inhibitors (PPIs)? Proton pump inhibitors (PPIs) are among the most commonly used medications in the world. They reduce the production of acid by blocking the enzyme in the wall of the stomach that produces acid. Acid is necessary for the formation of most ulcers in the oesophagus, stomach, and duodenum, and the reduction of acid with PPIs prevents ulcers and allows any ulcers that exist in the oesophagus, stomach, and duodenum to heal. PPIs are prescribed to treat acid-related conditions such as: Esophageal, duodenal and stomach ulcers NSAID-associated ulcer Ulcers Gastroesophageal reflux disease (GERD) Zollinger-Ellison Syndrome…
Neuroendocrine Cancer Hormonal Syndromes – a witch’s brew
One of the key awareness messages for Neuroendocrine Cancer is the hormonal syndromes that can often accompany the diagnosis for many people. As it's a difficult disease to diagnose, many people struggle with these syndromes for some time before formal diagnosis of Neuroendocrine Cancer. Some continue to struggle after. Neuroendocrine Cancer can often be uncannily quiet, but the tumours can be 'functional' and over-secrete certain hormones to add or introduce symptoms that mimic many other diseases or conditions, such as Irritable Bowel Syndrome, Menopause, Heart disease and Asthma. In addition to common symptoms of flushing and diarrhea, others include…
Living with Neuroendocrine Cancer – the 7 Year Itch
I quite like the Facebook memory thing. This morning I got a reminder of a post I made from 7 years ago whilst I was in hospital recovering from my 9 Nov surgery. It had taken 12 days for me to feel strong enough to venture onto social media with a simple message "I'm feeling perkier". For those not familiar with English localisms, it just means lively, spirited, bright, sunny, cheerful, animated, upbeat, buoyant, bubbly, cheery, bouncy, genial, jaunty, chirpy, sprightly, vivacious, in fine fettle, full of beans, bright-eyed and bushy-tailed. I guess I met some of these descriptors most…