Many of you may have seen the article in the Express published online on Saturday 28th May: Cancer: The ‘griping’ feeling patients often endure for ‘several years’ before diagnosis by Solen Le Net.
We heartily welcome the increased awareness this article may raise about Neuroendocrine Cancer – however, there are a few key points we think are important to address.
We agree that cancer is a complex disease that can develop in many different ways leading to a number of different signs and symptoms. Symptoms can differ for each cancer type, usually reflecting the organ or type of cell that is affected and how it develops.
Although they may produce similar symptoms there are different types of cancer that may affect the bowel and/or bowel function:
- Adenocarcinoma (more commonly referred to as bowel cancer) is the most common and can occur anywhere in the bowel – usually large bowel (colon) through to rectum. There are certain genetic conditions that may increase the risk of colon and/or rectal adenocarcinomas – these include include Lynch syndrome, FAP (Familial Adenomatous Polyposis) and MAP (MUTYH Associated Polyposis) – further information is available here
- Neuroendocrine Cancer, though considered uncommon or even rare, is increasing in incidence and is the most common cancer of the small bowel. Less frequently it can occur in the large bowel (colon) and / or rectum. They are not necessarily associated with some of the genetic conditions seen in the more common form of large bowel and rectal cancers – however if you have a family history of bowel cancer and / or one of the genetic conditions mentioned above – this does need to be included in your assessment – as colorectal cancer can occur alongside colorectal neuroendocrine cancer.
- Other less common types of bowel cancer include Squamous Cell tumours, Lymphoma, Sarcoma and Melanoma.
Neuroendocrine Cancer starts in specialised cells that are found throughout the body – these are neuroendocrine cells : cells that release hormones to help maintain normal bodily functions.
But even within this uncommon cancer group there are 2 key types – depending on the proliferation (rate of growth)and abnormal changes seen within the cell (differentiation):
- Neuroendocrine Tumours (NETs) show some abnormal changes (they are well-differentiated) and have a slow to rapid proliferation – graded 1-3. The higher the grade, the more aggressive the cancer.
NETs may release too much of the hormone the cells are usually responsible for. - In Neuroendocrine Carcinomas (NECs), the cells have become very abnormal (poorly-differentiated) and have a rapid proliferation rate – and so are grade 3.
NECs are rarely associated with cell specific excess hormone release.
This distinction, between NETs and NECs, is important – not just in terms of how they may cause symptoms leading to diagnosis – but also in terms of how they are diagnosed and how they are treated.
- Small bowel and Rectal Neuroendocrine Cancers are predominantly, but not exclusively, NETs
- Large bowel (colon) Neuroendocrine Cancers are predominantly, but not exclusively, NECs.
Symptoms
“When you do have symptoms, they are usually caused by the growth of cancer. Or by the Neuroendocrine Cancer spreading to other parts of the body. You can have symptoms caused by the hormones made by the tumour but this is rare.” CRUK spokesperson
When a tumour is left to grow, it can block the bowel , causing obstruction, this can lead to a griping pain in the tummy, bloating, constipation, being unable to pass wind and feeling or being sick.
However, many neuroendocrine cancers are asymptomatic (show no symptoms) – at least in the early stages of development – especially if the tumour is not releasing excess levels of hormones.
Large bowel and rectal neuroendocrine cancers may develop similar symptoms to the more common (adenocarcinoma) cancers that can occur. Small bowel symptoms may be less specific.
If the tumour does release a surplus of hormone, more common in (small bowel) NETs, symptoms may mimic certain common benign conditions such as Irritable Bowel Syndrome, food intolerances and / or menopause . They can include 2 or more of the following : skin flushing, palpitations, diarrhoea, tummy cramping and / or wheezing or shortness of breath.
How are Neuroendocrine Cancers treated?
The treatment for neuroendocrine cancer hinges on a number of factors, including where the cancer started, the degree of cell abnormality (differentiation) and proliferation (grading – that is how slowly or rapidly the cells are growing) – is it a NET or a NEC? – and whether the cells are producing normal or excess amounts of hormone.
More information on small bowel, large bowel, rectal and other Neuroendocrine Cancers can be found on our website.
The importance of early diagnosis
Treating cancer in the initial stages increases the odds of a favourable outcome, but because symptoms can be slow to appear, early detection and accurate diagnosis can be delayed.
However, in the UK the comprehensive bowel screening programme – and, importantly, more people taking up the invitation of bowel screening – is starting to make a difference.
Increasing the number of people being diagnosed at an earlier stage in their disease, increases the chance of cure . . .
. . . and we are already starting to see an increase in the number of Rectal Neuroendocrine Cancers being diagnosed at an early stage – because of bowel screening.
Neuroendocrine Cancers of the Large Bowel and Rectum are rare – but the incidence is increasing – in part due to increased awareness , in part due to advances in diagnostic tests and screening programmes.
However, research is ongoing to establish why neuroendocrine cells become malignant, how we can better diagnose them earlier and discover more effective treatments – with the ultimate goal of cure or even prevention.
Bowel screening aims to find bowel cancer early, before symptoms develop. 
If you are registered with a GP, you will be offered your first bowel screening test between the ages of 50 and 60. This depends on which country in the UK you live in.
There are different bowel screening programmes in each nation.
In England and Scotland :
- You will be sent a FIT home screening kit.
- If you are older than 75, you will not automatically be sent a home test. But you can still take part in screening if you choose to. You can call the bowel screening helpline and ask to be sent a test kit.
In Wales and Northern Ireland :
- You will be sent a FOB home screening kit
- If you have an unclear result, you may also be sent a FIT test.
- You cannot request a kit if you are 75 or older.
FOB and FIT tests are very similar.
- They both check for hidden blood in poo, which can be a sign of polyps or any kind of bowel cancer.
- The tests come as a home screening kit.
- You collect a small sample of your poo and send it to a laboratory.
- In the lab it is checked for tiny amounts of blood.
- The main difference between the two tests is that you only need to send one sample of poo for the FIT test. The FOB test needs three samples to get a complete result.
Further information on FIT and FOB tests is available from Macmillan here
FIT test video (in English and other languages including BSL) can be viewed here