Neuroendocrine Cancer – the diarrhea jigsaw

NETCancer Diarrhea Jigsaw

Diarrhea can be a symptom of many conditions but it is particularly key in Neuroendocrine Tumour (NET) Syndromes and types, in particular, 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 problems such as hyperthryoidism, mastocytosis or Addison’s disease (which may be secondary illnesses in those with NETs).  It’s also possible that ‘non-sydromic’ issues such as stress and diet are contributing. It could be caused by other things such as Irritable Bowel Syndrome (IBS). Yes, believe it or not, NET Patients can get normal diarrhea causing diseases too!

Define Diarrhea

I want to give a general definition of diarrhea as there are many variants out there. In general, they all tend to agree that diarrhea is having more frequent, loose and watery stools. Three or more stools per day seems to be the generally accepted threshold, although some sites don’t put a figure on it.  It’s not pleasant and just about everyone on the planet will suffer it at some point in their life, perhaps with repeated episodes. Normally it’s related to some kind of bug, or something you’ve eaten and will only last a few days before it settles (acute diarrhea). Diarrhea lasting more than a couple of weeks is considered chronic and some people will require medical care to treat it.  It can also be caused by anxiety, a food allergy/intolerance or as a side effect of medicine. Pharmacists and GPs will be seeing many patients with this common ailment every single day of business.

Diarrhea induced by a Syndrome

When you consider the explanation above, it’s not really surprising that diarrhea related symptoms can delay a diagnosis of Neuroendocrine Cancer (and most likely other cancers too, e.g. pancreatic cancer, bowel cancer). For example, diarrhea is the second most common symptom of Carcinoid Syndrome (Flushing is actually the most common) and is caused mainly by the oversecretion of the hormone Serotonin from the tumours. Please note diarrhea in other types of syndromes or NETs may be caused by other hormones, for example it may also be caused by excess calcitonin in the case of Medullary Thyroid Carcinoma or VIP in the case of a functional pNET known as VIPoma. I’ve heard stories of people being told they have IBS or something similar for years before they received what is now a late diagnosis and at an advanced cancer stage. This is only one of the reasons why NETs is not an easy condition to diagnose, although it is possible that some people actually had IBS and it was masking the NET. Even after treatment to remove or reduce tumours, many people will remain syndromic and need assistance and treatment to combat diarrhea induced by a NET syndrome (see below).

Diarrhea as a Consequence (Side effect) of Treatment for Neuroendocrine Cancer and Other Conditions

All cancer treatments can have consequences and Neuroendocrine Cancer is definitely no exception here. For example, if they chop out several feet of small intestine, a chunk of your large intestine, chunks (or all) of your stomach or your pancreas, your gallbladder and bits of your liver, this is going to have an effect on the efficiency of your ‘waste disposal system’. One effect is that it will now work faster! Another is that the less effective ‘plumbing’ may not be as efficient as it was before.  There are also knock-on effects which may create additional issues with the digestive system including but not limited to; Malabsorption and SIBO.  I recommend you read my posts on Malabsorption and SIBO.

Surgery can often be the root cause of diarrhea.  A shorter gut for example, means shorter transit times presenting as increased frequency of bowel movements.  Another example is the lack of terminal ileum can induce Bile Acids Malabsorption (BAM) (sometimes known as Bile Salts Malabsorption) in degrees of severity based on size of resection. Lack of a gallbladder (common with NETs) can also complicate.  Bile Acids are produced in the liver and have major roles in the absorption of lipids in the small intestine. Following a terminal ileum resection which includes a right hemicolectomy, there is a risk that excess Bile Acids will leak into the large intestine (colon) via the anastomosis (the new joint between small and large intestines).  This leakage can lead to increased motility, shortening the colonic transit time, and so producing watery diarrhea (or exacerbating an existing condition). Although this condition can be treated using bile acid sequestrants (i.e.  Questran), it can be difficult to pinpoint it as the cause.

Surgery of the pancreas can also produce effects such as exocrine pancreatic insufficiency which can lead to a malabsorption condition known as steatorrhea which may be confused with diarrhea (although some texts call it a type of diarrhea).   It isn’t really diarrhea but it may look like it given the presentation of the faeces and patients may suffer both diarrhea and steatorrhea concurrently.  Patients will recognise it in their stools which may be floating, foul-smelling, greasy (oily) and frothy looking. Treatment options will mainly include the use of Pancreatic Enzyme Replacement Therapy or PERT for short (Creon etc).

Many non-surgical treatments can also cause diarrhea, including but not limited to; somatostatin analogues (see below), chemotherapy, biological targeted therapy (e.g. Everolimus, Sunitinib), radiotherapy.

Somatostatin analogues are an interesting one as they are designed to inhibit secretion of particular hormones and peptides by binding to the receptors found on Neuroendocrine tumour cells. This has the knock-on effect of inhibiting digestive/pancreatic enzymes which are necessary to break down the fat in our foods leading to Malabsorption of important nutrients.  This may worsen the steatorrhea in pancreatic NET patients but also lead to steatorrhea in others with non-pancreatic locations who have been prescribed these drugs.

Other conditions may actually be the cause of the diarrhea or the treatment for those conditions.  For example, it is possible that people actually do have Irritable Bowel Syndrome (IBS).  Treatment therapy for common conditions may also be contributing, for example the use of Proton Pump Inhibitors for acid reflux.

 

Treatment for Syndrome Induced Diarrhea 

Like many other NET patients, I’m on a 28 day injection of somatostatin analogues (in my case Lanreotide).  Both Octreotide and Lanreotide are designed to reduce the effects of NET syndromes and therefore can often make a difference to syndrome induced diarrhea. These drugs also have anti-tumour effect and so even if you are not syndromic or they do not halt or adequately control syndrome induced diarrhea, they are still a valuable contribution to NET treatment.

Some syndromic patients find they still have diarrhea despite somatostatin analogues and they end up having ‘rescue shots’ or pumps for relief (both of these methods tend to be Octreotide based).  (Hopefully they are not getting confused between diarrhea caused by the non-syndrome effects – see above).  Some have more frequent injections of the long acting versions of somatostatin analogues which has the effect of increasing the dosage.  There’s a new drug available for those whose carcinoid syndrome induced diarrhea is not adequately controlled or perhaps they are unable to have somatostatin analogues as a treatment. Telotristat Ethyl works by inhibiting tryptophan hydroxylase (TPH), a chemical reactor involved in the manufacture of serotonin, which is the main cause of syndrome induced diarrhea.  It was approved by the US FDA in February 2017, EU areas in September 2017, and is on the way to being approved elsewhere.  Read about this drug here.

telotristat-etiprate-clinical-trial-serotonin-as-a-key-driver-of-carcinoid-syndrome

Sorting out the symptoms – post diagnosis

I like to describe this as the Neuroendocrine Cancer jigsaw. It’s a really difficult one and sometimes you cannot find a piece, or the pieces won’t fit. However, metaphorically speaking, the missing piece might be a NET specialist presentation, a comment, statement or view from another patient, a link to an article from a reputable source, or even something you do to improve your lot – there might even be trial and error involved. It might even be this blog post!

How do you work out whether diarrhea is caused by a hormone producing tumour or by the side effects of treatments? There’s no easy answer to this as both might be contributing. One crude but logical way is to just accept that if you have normal hormone markers, for example 5HIAA (there could be more for other tumour/syndrome types), and you’re not really  experiencing any of the other classic symptoms, then your syndrome might be under control due to your treatment (e.g. debulking surgery and/or somatostatin analogues, or another drug). My Oncologist labels me as ‘non-syndromic’ – something which I agree with. I’m 99.999999% sure my issues are as a result of the treatment I’ve had and am receiving.

This disease is so individual and there are many factors involved including the type of syndrome/NET, patient comorbidities and secondary illnesses, consequences of the surgery or treatments performed, side effects of drugs – all of which is intermingled with suspicion and coincidence – it’s that jigsaw again!  I always like to look in more detail to understand why certain things might be better than others, I always challenge the ‘status quo’ looking to find a better ‘normal’.  I really do think there are different strategies for syndrome induced diarrhea and that which is a result of treatment or a side effect of treatment.  There’s also different prices, with inhibitors costing thousands, whilst classic anti-diarrhea treatments are just a few pennies.  Adjustments to diets are free!

When I was discharged from hospital after the removal of my small intestinal primary, I was in the toilet A LOT (I was actually in the toilet a lot before I was discharged – check out my primary surgery blogs here) .  My surgeon did say it would take months to get back to ‘normal’ – he was right and it did eventually settle – although my new ‘toilet normal’ was soft and loose and several times daily.  My previously elevated CgA and 5HIAA were eventually back to normal and my flushing had disappeared.  I didn’t have too many issues with diarrhea before diagnosis.  Deduction:  my issues are most likely not syndrome induced.

I read that many people find basic ‘Loperamide’ (Imodium) helps and I tend to agree with that if you are non syndromic and just need that little bit of help.  I decided long time ago I would not become ‘hooked’ and only really take it for two purposes:  1) if I have a bad patch and 2) if I’m going on a long journey (i.e. on a plane perhaps).  I estimate I’ve used 4 packets in as many years.  Loperamide decreases the activity which causes intestinal motility (peristalsis). This has the effect of increasing the time material stays in the intestine therefore allowing more water to be absorbed from the fecal matter.  Ideal for those with a shorter bowel due to surgery and advice from a medical professional is always advisable.  To reduce the risk of malabsorption induced diarrhea and steatorrhoea, both of which can lead to loss of valuable nutrients, the use of Pancreatic Enzyme Replacement Therapy (PERT) might need to be introduced as required by your NET specialist.

Have a look at Enterade – the results from trials look good.

enterade

Clearly, I cannot offer any professional medical advice on coping with diarrhea, I can only discuss my own situation and what I found worked for me. Don’t forget, like many diseases, what works for one, might not work for another. However, I did tackle my problems following the advice of an experienced dietitian who specialises in NET Cancer. That said, I was ‘sleep walking’ for over 2 years thinking my issues were just part of the way things were after my treatment.  I was wrong about that!

As for my own strategy,  here’s things that helped me:

  • made some changes to diet (they were not huge changes),
  • included supplementation where necessary,
  • reduced stress as far as is practical to do,
  • exercise,
  • maintained a diary to help with monitoring progress or setbacks,
  • hydration is also important (….still working on that one).
  • started taking PERT (Creon) on 23 Dec 2017 (changed to Nutrizym Feb 2019) but looks reasonably positive so far.

With no fancy and expensive drugs, I’ve gone from 6-8 visits to 1-2 visits (as a daily average, it’s actually 1.5).  This didn’t happen overnight though, it took a lot of time and patience.  All of this doesn’t mean to say I don’t have issues from time to time …… because I do!


In summary, I think it’s important that people be sure what is actually causing their diarrhea after diagnosis so that the right advice and the optimum treatment can be given.

Listen to Dr Wolin talking about this particular jigsaw puzzle – click here

Also see a nice article that come out of NANETS 2017 – click here

Of course, some people sometimes have the opposite effect but that’s in another blog here – Constipation

Thanks for reading

Ronny

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Serotonin – the NET effect

A team of researchers from Case Western Reserve University School of Medicine have used high-powered microscopes for the first time to view serotonin activating its receptor

Background

I’d never heard of Serotonin until I was diagnosed with Neuroendocrine Cancer in 2010.  It is frequently discussed, often with contrasting views from the respondents. One common assumption/question is that it is responsible for many things that can go wrong with Neuroendocrine Cancer patients who have serotonin-producing tumours. “It’s the hormones” is an easy assumption to make or an easy answer to give in response to a complex set of circumstances.  It’s difficult to get a definitive answer and the science behind the behaviour of our hormones isn’t really 100% tied down.

You may see serotonin referred to as a ‘neurotransmitter’, a ‘chemical’ and a ‘hormone’ – this is complex but it is my understanding that it can add context in respect the role/location of the serotonin, e.g. chemical and hormone are essentially synonymous and are endocrine related whereas neurotransmitter is concerned with the nervous system (the neuro in neuroendocrine) and the brain (more on this below). Consequently, I’ll keep this as basic as I can (author’s note on completion – it was not easy!).

Serotonin and NETs

One thing which is widely accepted and agreed…… Serotonin is definitely involved in Neuroendocrine Tumours, in particular, those resulting in carcinoid syndrome which can manifest as a number of symptoms including but not limited to flushing and diarrhea.  Although serotonin is one of the main ‘hormones’ released in excess by certain NETs (mainly midgut), it is not thought to be the main culprit behind some of the symptoms produced by Carcinoid Syndrome.  For example, flushing, the most common symptom (and a cardinal one) is thought to be caused by a number of hormones/peptides – too many to list but the main ones are histamine (particularly foregut), tachykinins (Substance P), bradykinins, prostaglandins …….. and I’m sure serotonin’s in there too!  It does, however, appear to be massively guilty in causing carcinoid syndrome diarrhoea, desmoplasia, and carcinoid heart issues.

Where does Serotonin come from?

Serotonin’s technical name is 5-hydroxyltryptamine (5-HT).  It is converted from 5-Hydrotryptophan (5-HTP) which is also known as oxitriptan. 5-HTP is a naturally occurring amino acid and chemical precursor as well as a metabolic intermediate in the biosynthesis of serotonin (…..and melatonin) from tryptophan. Tryptophan is interesting as that brings in one of the missing pieces of the jigsaw – food!  Tryptophan cannot be manufactured in the body, it must be brought in via diet. There is no serotonin in food, it is only manufactured in the body.

Tryptophan in food enters the body and serotonin is created by a biochemical conversion process which combines tryptophan (essentially a protein) with tryptophan hydroxylase (TPH), a chemical reactor. I suspect other substances might be involved in that process.  There are two forms of tryptophan hydroxylase – TPH1 and TPH2, which are encoded on two independent genes. TPH1 is linked to peripheral serotonin while TPH2 is related to brain serotonin.

While serotonin cannot cross the blood-brain barrier, tryptophan can, and once there, almost all of it is converted to serotonin. Unlike, peripheral setotonin where only a small percentage is used to generate serotonin. Just to emphasise that NET dietitians do not say to avoid foods containing tryptophan other than at the time of marker testing (see below and nutrition Blog 4). When you look at the role in brain serotonin, this might have an adverse effect. 

Are you happy with your serotonin?

Serotonin Inhibitors

The introduction of Somatostatin analogues (SSAs) such as Octreotide and Lanreotide, help reduce the secretion of “tumour-derived serotonin”  by binding to its receptors on the outside of the cell.  If you ever wondered why receptors are important, please check out my blog on this subject (click here).

I mentioned tryptophan hydroxylase (TPH) above and that is actually very interesting as this is how Telotristat Ethyl (XERMELO) is able to help with the symptoms of Carcinoid Syndrome diarrhea (not adequately controlled by SSAs) or where patients are unable to be treated by somatostatin analogues for whatever reason. It’s a potent inhibitor of TPH which will disrupt the manufacturing of tumour-derived serotonin. There is also evidence that it can help reduce the effects or halt the growth of the fibrosis leading to carcinoid heart disease.  Slight digression but useful to aid/enhance understanding at this point.  Read about Telotristat Ethyl here.

Serotonin and the Brain

There is constant discussion and assumption that serotonin-producing tumours are somehow causing depression, anxiety and rage.  Not as simple as that, it’s way more complicated.  Certain NETs can overproduce serotonin in the gut but the issues concerning depression and anxiety are normally associated with low levels of serotonin in the brain.

“>Cancer anger” is a normal response to fear, despair and grief – a range of feelings which cancer brings into our lives. It can show as frustration, irritability, emotional withdrawal or aggression. You can feel it whether you have been diagnosed or you are a relative or friend. Cancer anger can happen at any stage of the illness, even years after treatment. I know that many people with cancer suffer from depression, anxiety and anger but they do not all have serotonin-producing tumours.  What they do have is a life threatening and/or life changing condition which is bound to have an effect on mind as well as body.  Hormones including Serotonin are natural substances found in the body and not just there to service NETs.

Serotonin is separately manufactured in the brain (~10%) and in the gastrointestinal tract (~90%).  The serotonin in the brain must be manufactured in the brain, it cannot be directly increased or reduced external to the brain, i.e. it cannot be directly reinforced by gut serotonin (peripheral serotonin). It follows that ‘brain serotonin’ and ‘gut serotonin’ are held in separate stores, they are manufactured in those stores and remain in those stores – there is no cross-pollination. This is managed by something called the blood-brain-barrier (BBB). Therefore, excess serotonin from NETs does not infiltrate the brain. As low-level of ‘brain serotonin’ is often linked to depression, it also follows that it’s possible to have high levels of serotonin in the gut but low levels in the brain.

My simple way of thinking about such things as outlined above, is that low levels of tryptophan in the brain might be contributing to low levels of serotonin in the brain.  To clarify that, I researched the reasons why there could be low serotonin in the brain.

First, let’s dismiss any connection that the type of anti-depressant is called Selective serotonin reuptake inhibitors (SSRIs) is involved. It’s thought that SSRIs work by increasing serotonin levels in the brain. Serotonin is a neurotransmitter (a messenger chemical that carries signals between nerve cells in the brain). We already discussed that it’s thought to have a good influence on mood, emotion and sleep. After carrying a message, serotonin is usually reabsorbed by the nerve cells (known as “reuptake”). SSRIs work by blocking (“inhibiting”) reuptake, meaning more serotonin is available to pass further messages between nearby nerve cells. So tryptophan or peripheral serotonin are not really involved.

It would be too simplistic to say that depression and related mental health conditions are caused by low serotonin levels (in the brain), but a rise in serotonin levels (in the brain) can improve symptoms and make people more responsive to other types of treatment, such as Cognitive Behaviour Therapy (CBT).  It’s also too simple to suggest that NET patients get depression and anxiety due to all the “hormones” these tumours produce.  Of course hormones can be involved in depression and anxiety but hormones aren’t their just for NET patients.  Cancer patients without hormone secreting tumours also get anxiety and depression so it’s possible that NET patients can get depression and anxiety in the same way.

It should also be noted that the precursor to serotonin, tryptophan, does pass through the BBB and it is therefore possible that tryptophan depletion can lead to less availability in the brain for the manufacture of brain serotonin.  Tryptophan depletion can be caused by dietary restrictions (i.e. lack of tryptophan foods) and also by the effects of certain types of tumours as excess serotonin is made leading to less availability of tryptophan.  Both could lead to low serotonin in the brain as less tryptophan gets there. It follows that foods containing tryptophan remain important in order to help maintain normal brain serotonin levels.

Measuring Serotonin levels

Measuring levels of serotonin is important in both diagnosis and management of certain NETs – although it’s probably sensible to test all potential NET patients during diagnosis when the type of tumour is not yet known.  Testing for tumour markers will differ between countries and within countries but the most common standard for testing Serotonin appears to be 5-HIAA (5-hydroxyindoleacetic acid) either via a 24-hour urine test or via a plasma version (mainly used in USA but now creeping into UK).  5-HIAA is the output (metabolite) of 5-HT (Serotonin). Not to be confused with the less reliable ‘serum serotonin’ which is a different test.

Another frequently asked question about serotonin tests is whether they are testing the amount in the brain or the gut. The answer is …… they are testing the levels in the blood. Furthermore, if you are measuring serotonin as an indicator for Carcinoid Syndrome, it has to be remembered that the majority of serotonin is in the gut, so even if serotonin levels in the brain were being measured alongside the gut levels, I don’t believe it would  influence the result in any significant way (but I have no science to back that up). It also has to be remembered that serum serotonin and 5HIAA are not absolute tests, they are not 100% sensitive, they are simply indicators of a potential problem. There are methods of measuring brain serotonin but it is very complex and beyond the purposes of this article.  However, I would just add that it is the reuptake of Serotonin in the brain (plus some other stuff) that can cause depression, not the actual level or amount in the brain.

I intentionally did not mention the other common test (Chromogranin A) or other markers as they are measuring different things but you can read about in my Testing for Markers blog.

Serotonin Video with myself and Dr Mike Morse

I made a video in 2019 with Dr Mike Morse sponsored by Lexicon Pharmaceuticals, Inc.  It’s all about Carcinoid Syndrome with a slant towards hormones, in particular Serotonin. Entitled “Likely Suspects: How Hormones May Lead to Carcinoid Syndrome – What People Living With Carcinoid Syndrome Need to Know”

You need to register to watch although some of you will already be registered and just need an email to login to see the this webcast. The one I’m featured in is the latest in a series on the subject and I’d like to break the record for views please! Please help me achieve this 💙 I would also love to get your feedback and sincerely hope you will find the time to listen in.  Please also find the time to complete the survey at the end.  Thanks

Click on the link here: www.CarcinoidWebcast.com

Don’t forget to press the play button and ensure your sound is turned up, particularly on mobile devices.

webcast morse allan

Summary

I did say it was a difficult jigsaw!

Thanks for reading

Ronny

I’m also active on Facebook. Like my page for even more news. I’m also building up this site here: Ronny Allan

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Telotristat Ethyl (XERMELO®) – an oral treatment for Carcinoid Syndrome Diarrhea not adequately controlled by Somatostatin Analogues

Telotristat Ethyl is an extremely significant introduction to the treatment of Carcinoid Syndrome diarrhea. It’s the first addition to the standard of care in more than 16 years and the first time an oral syndrome treatment has been developed.  The drug was previously known as Telotristat Etiprate but was changed to Ethyl in Oct 2016. ‘Etiprate’ was previously a truncation of ‘ethyl hippurate’.  The brand name is XERMELO® 

UPDATE MARCH 2018 

The March 2018 issue of Clinical Therapeutics provides the first report of the effects of XERMELO on changes in weight in patients with neuroendocrine tumors (NETs) and carcinoid syndrome that participated in the TELESTAR study. You have to remember that XERMELO is approved for those with carcinoid syndrome diarrhea not adequately controlled by somatostatin analogues (author’s note – i.e not for diarrhea caused by (say) side effects of surgery).

Of the 120 patients with weight data available, up to 32.5% of patients treated with XERMELO experienced significant, dose-dependent weight gain (≥3% from baseline). Only 5.1% of patients on placebo experienced weight gain. Importantly, patients with weight gain experienced improvement in carcinoid syndrome control, as seen in reduction of bowel movement frequency and in parameters of nutritional status associated with positive changes in patient-reported outcomes compared with patients with stable weight or weight loss. Those patients also experienced reduced u5-HIAA levels. Patients with weight gain also experienced fewer serious adverse events than patients with stable weight or weight loss.

(see link below)

Who is the drug for?

The drug may be of benefit to those whose carcinoid syndrome diarrhea is not adequately controlled by somatostatin analogues (Octreotide/Lanreotide). It doesn’t replace somatostatin analogues – it is an additional treatment alongside (although I have heard of patients in the US being subscribed who are not receiving somatostatin analogue treatment)

Where is it currently approved?

The US FDA approved the drug 28 February 2017.

On 19 September 2017,the European Commission approved Xermelo® (telotristat ethyl) for the treatment of carcinoid syndrome diarrhea in patients inadequately controlled by somatostatin analogue therapy after the scientific committee of the EMA (known as Committee for Medicinal Products for Human Use (CHMP)) adopted a positive opinion recommending the approval of Xermelo® (telotristat ethyl) 250 mg three times a day for the treatment of carcinoid syndrome diarrhea in combination with somatostatin analogue (SSA) therapy in adults inadequately controlled by SSA therapy. The Ipsen press release is here.  Clearly some action will be required in EC national countries before the drug becomes available through the appropriate healthcare systems.


On 17 Oct 2018, Health Canada announced approval for Canadian NET patients – click here.

For all other countries please note that Ipsen will pursue a worldwide regulatory plan for marketing authorisation submissions in the territories in which it operates. Once approved, Ipsen will be distributing the drug in all countries less USA and Japan where Lexicon retains the rights. Outside USA and Europe will be constrained by national approval timelines.

How does it work?

In the simplest of terms, the drug is an inhibitor of the enzyme tryptophan hydroxylase (TPH).  TPH is the rate-limiting enzyme in serotonin synthesis which converts tryptophan (an essential amino acid which comes from diet) to 5-hydroxytryptophan, which is subsequently converted to serotonin, one of the main causes of carcinoid syndrome effects including carcinoid heart disease.  The trial data indicates that Telotristat ethyl significantly reduced the frequency of bowel movements. Furthermore, it was also associated with “significantly reduced levels of urinary 5-HIAA“, a marker for systemic serotonin levels, which are typically elevated in severe carcinoid syndrome.  Essentially it works by reducing the manufacture of Serotonin so it’s it may not have any effect on diarrhea not caused by syndrome (i.e. post surgery etc).

telotristat-etiprate-clinical-trial-serotonin-as-a-key-driver-of-carcinoid-syndrome

Resources for your perusal:

  • You can read more about the trial data in a summary by Dr Matthew Kulke (Dana Farber) by CLICKING HERE (latest review from 2017 ASCO).
  • There is also an excellent summary in video form by Dr Lowell Anthony (University of Kentucky) by CLICKING HERE. (“any reduction in diarrhea is meaningful“).
  • The detailed output from the trial (results) can be found by CLICKING HERE.
  • Great 2016 article from ASCO (American Society of Clinical Oncologists) can be found by CLICKING HERE.
  • FDA Approval.  CLICK HERE
  • Lex Pharma press release on approval.  CLICK HERE
  • EU Approval (Ipsen Press Release).  CLICK HERE
  • The manufacturer Lex Pharma have established a dedicated site – CLICK HERE
  • 2018 revised clinical data – CLICK HERE

Thanks for reading

Ronny

I’m also active on Facebook.  Like my page for even more news.  I’m also building up this site here: Ronny Allan

Disclaimer

My Diagnosis and Treatment History

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Sign up for my twitter newsletter

Remember ….. in the war on Neuroendocrine Cancer, let’s not forget to win the battle for better quality of life!

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