ASCO (American Society of Clinical Oncology) is one of the biggest cancer conferences in the world normally bringing together more than 30,000 oncology professionals from around the world to discuss state-of-the-art treatment modalities, new therapies, and ongoing controversies in the field. As Neuroendorine Tumors is on a roll in terms of new treatments and continued research, we appear to be well represented with over 20 ‘extracts’ submitted for review and display. This is fairly complex stuff but much of it will be familiar to many. I’ve filtered and extracted all the Neuroendocrine stuff into one list providing you with an easy to peruse table of contents, complete with relevant linkages if you need to read more. For many the extract title and conclusion will be sufficiently educational or at least prompt you to click the link to investigate further. Remember, these are extracts so do not contain all the details of the research or study. However, some are linked to bigger trials and linkages are shown where relevant. I’ve also linked to some of my blog posts to add context and detail.
I’m hoping to capture any presentations or other output from the meeting which appears to be relevant and this will follow after the meeting. I will also be actively tweeting any output from the live event (for many cancers, not just NETs).
There’s something for everyone here – I hope it’s useful.
Conclusions: Objective response to PRRT defines a subset of patients with markedly improved PFS. SUVave 21.6 defines a threshold below which patients have a poor response to PRRT. This threshold should be taken forward into prospective study.
Check out my recent blog discussing ‘Theranostic pairing” – click here
Conclusions: The duration of SSA use was positively associated with QoL benefit among CS patients. This may be explained by long-term effectiveness of SSAs or selection bias favoring patients with more indolent disease. Future studies will be needed to distinguish between these possibilities.
Conclusions: The incidence of weight gain was dose-related on TE and was greater than that on pbo. It was possibly related to a reduction in diarrhea severity, and it may be a relevant aspect of TE efficacy among patients with functioning metastatic NETs. Clinical trial information: NCT01677910
Conclusions: A pre-PRRT analysis of circulating NET genes, the predictive quotient index comprising “omic” analysis and grading, is validated to predict the efficacy of PRRT therapy in GEP and lung NETs.
Conclusions: CAPTEM shows activity in neuroendocrine tumor of unknown primary. Currently FDA approved treatment options for grade I and grade II GI NETs includes somatostatin analogs and everolimus. Both of which are cytostatic and of limited use in case of visceral crisis or bulky disease where disease shrinkage is required. CAPTEM should be considered for grade II NETS of unknown primary.
Conclusions: This is the first multi-center study in Mexico. Which reflects the clinical characteristics of the NET_GET. The results differ in their epidemiology from that reported in other countries. However, the clinical and therapeutic results are very similar.
Conclusions: These data suggest that serotonin is secreted by nonfunctioning tumors, but does not reach the threshold required for clinical carcinoid symptoms. Monitoring 5HIAA and CgA may be useful during LAN treatment of nonfunctional GEP NETs. Clinical trial information: NCT00353496
Conclusions: CLARINET OLE suggests sustained antitumor effects with LAN 120 mg in enteropancreatic NETs irrespective of tumor origin, and suggests benefits with LAN as early treatment. Clinical trial information: NCT00842348
Conclusions: Pts showed improvement in CS symptoms of flushing and diarrhea and reduction in 5HIAA levels with LAN treatment, indicating efficacy of LAN regardless of prior OCT use. Transition from OCT to LAN was well tolerated among prior OCT pts in ELECT. Clinical trial information: NCT00774930
Conclusions: These findings highlight the utility of molecular classification to identify distinct NET tumor types/subtypes to improve diagnostic precision and treatment decision-making. In addition, significant differences in the distribution of molecular diagnoses of NET subtype by age and gender were identified.
Conclusions: In this poor prognosis G3 NET cohort of whom 77% had received prior chemotherapy, a median OS of 18 months from start of PRRT is encouraging and warrants further study. PRRT is a promising treatment option for patients with G3 NET with high somatostatin-receptor expression selected by SSRI.
Conclusions: Occurrence of documented carcinoid crisis was low in this high-risk population. However, a significant proportion of patients developed hemodynamic instability, suggesting that carcinoid crisis is a spectrum diagnosis and may be clinically under-recognized. Use of octreotide was not associated with risk of carcinoid crisis or hemodynamic instability; however, this analysis was limited by our modest sample size at a single institution. There remains a need to establish an objective definition of carcinoid crisis and to inform standardization of periprocedural use of octreotide for at-risk patients.
Conclusions: By assessing patients with GI NET from two independent US claim databases, this study suggested that patients diagnosed with CS were 2-3 times more likely to be diagnosed with liver disorder, enlargement of lymph nodes, or abdominal mass, than those without CS during the one year prior to CS diagnosis. Future studies using patient medical charts are warranted to validate and interpret the findings. These findings, when validated, may aid physicians to diagnose CS patients earlier.
Conclusions: Radiological progression within 12 months of completion of PRRT is associated with a worse outcome in terms of OS. Patients with greater liver involvement and highest CgA levels are more likely to progress within 12 months of treatment completion. Earlier treatment with PRRT in patients with radiological progression not meeting RECIST criteria may need to be considered. There may be a greater survival benefit if PRRT is given prior to the development of large volume disease.
Conclusions: To the best of our knowledge, this is the first population-based study to examine potentially relevant pre-existing symptoms, resource utilization and healthcare costs before NET diagnosis. NET patients were more likely to have certain conditions and incurred higher resource utilizations and costs in the year preceding diagnosis of NET.
Conclusions: This population-based study showed that elderly NET pts have significantly different prevalence of co-morbidities compared to non-cancer controls. The impact of these conditions on survival and therapeutic decisions is being evaluated.
Conclusions: In patients with SBNET with liver metastasis, higher tumor grade and post-operative chemotherapy increased risk of death. However, resection of the primary tumor along with liver metastasis improves the 5-year OS with complete cytoreduction providing the most benefit.
Role of 92 gene cancer classifier assay in neuroendocrine tumor of unknown primary. | 2017 ASCO Annual Meeting Abstracts
Conclusions: Tissue type ID was able to identify a primary site in NETs of unknown primary in majority (94.7%) of cases. The result had direct implication in management of patients with regards to FDA approved treatment options in 13/38 patients (pNETs, merkel cell and pheochromocytoma).
Conclusions: Radical loco-regional surgery for primary tumours combined with PRRT provides a novel, highly efficacious approach in metastasised NET. The NETest accurately measures the effectiveness of treatment.
Conclusions: Grade 3 GEP-NECs could be morphologically classified into well and poorly differentiated NETs. Additionally, among grade 3 GEP-NECs, there was a significant difference in ranges of Ki67 index between well and poorly differentiated NECs. Higher levels ( > 60%) of Ki67 index might be a predictive marker for efficacy of EP as a standard regimen in grade 3 GEP-NECs.
Check out my blog post on Gradingwhich has incorporated latest thinking in revised grade 3 classification
Seung Tae Kim
Theranostic trial of well differentiated neuroendocrine tumors (NETs) with somatostatin antagonists 68Ga-OPS202 and 177Lu-OPS201.
Conclusions: In this trial of heavily treated NETs, preliminary data are promising for the use of 68Ga-OPS202/177Lu-OPS201 as a theranostic combination for imaging and therapy. Additional studies are planned to determine an optimal therapeutic dose and schedule. Clinical trial information: NCT02609737
Conclusions: SREs in NEN patients with BM were not uncommon, especially in patients with grade 3 NEN and osteolytic metastases. Application of ART did not significantly alter median OS or TTSRE, no subgroup with a benefit of ART could be identified. The use of ART in NEN should be questioned and evaluated prospectively.
Conclusions: Rhenium Re 188 P2045, a radiolabeled somatostatin analog, may be used to both identify and treat lung cancer tumors. The ability to image and dose patients with the same targeted molecule enables a personalized medicine approach and this highly targeted patient therapy may significantly improve treatment of tumors that over express somatostatin receptor.
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 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 hypothalamus and some other tissues such as the pancreas and the gastrointestinal tract. However, it can only handle the normal release of hormones. When NET syndromes occur, the naturally occurring somatostatin is unable to cope. The word ‘analogue’ in the simplest of terms, means ‘manufactured’ and a somatostatin analogue is made to be able to cope with the excess secretion (in most cases).
Although there is hidden complexity, the concept of the drug is fairly simple. It can inhibit insulin, glucagon, serotonin, VIP, it can slow down bowel motility and increase absorption of fluid from the gut. It also has an inhibitory effect on growth hormone release from the pituitary gland (thus why it’s also used to treat a condition called Acromegaly). You can see why it’s a good treatment for those with NET syndromes, i.e. who suffer from the excess secretions of hormones from their NETs. Clearly there can be side effects as it also inhibits digestive enzymes which can contribute to, or exacerbate, gastro-intestinal malabsorption.
Please note somatostatin analogues are not chemo. There are two major types in use:
Octreotide – or its brand name Sandostatin. It is suffixed by LAR for the ‘long acting release’ version.
Lanreotide – brand name Somatuline (suffixed by ‘Depot’ in North America, ‘Autogel’ elsewhere)
So what’s the difference between the two?
A frequently asked question. Here’s a quick summary:
They are made by two different companies. Novartis manufactures Octreotide and Ipsen manufactures Lanreotide. Octreotide has been around for much longer.
The long-acting versions are made and absorbed very differently. Octreotide has a complex polymer and must be injected in the muscle to absorb properly. Lanreotide instead uses has a novel nanotube structure and is water based (click here to see a video of how this works). It is injected deep-subcutaneously and is therefore easier to absorb and is not greatly impacted if accidentally injected into muscle.
Their delivery systems are mainly via injections but are fundamentally different as you can see from the blog graphic which shows the differences between the long acting release versions. Octreotide long acting requires a pre-mix, whilst Lanreotide comes pre-filled.
The long-acting versions are 60, 90 and 120 mg for Lanreotide and 10, 20 and 30 mg for Octreotide.
Octreotide also has a daily version which is administered subcutaneously.
Octreotide has something called a ‘rescue shot’ which is essentially a top up to tackle breakthrough symptoms. It is a subcutaneous injection.
You can also ‘pump’ Octreotide using a switched on/off continuous infusion subcutaneously.
Other than for lab/trial use, to the best of my knowledge, there is no daily injection, rescue shot or ‘pump’ for Lanreotide that is indicated for patient use.
Whilst both have anti-tumour effects, there are differences in US FDA approval: Octreotide (Sandostatin) is approved for symptom control (not anti-tumor) whereas Lanreotide (Somatuline) is approved for tumour control. However, the US FDA recently added a supplemental approval for syndrome control on the basis that it is proven to reduce the need for short acting somatostatin analogues use – read more here. This supplementary approval followed the ELECT trial – results here.
Always refer to the patient information leaflet as it is not safe to assume that all healthcare professionals are familiar with the administration. Common issues include (but are not limited to): drug temperature requirements, injection site, pinching vs stretching skin, speed of injection.
Please note a new syringe for Lanreotide will be available in June 2019. Further information will be communicated to healthcare professionals in advance of this, to enable them to inform their patients, whom have been prescribed Lanreotide. In addition, the patient information leaflet included in the packet will have clear instructions for use. There will be a prominent yellow box located on the outer carton of the medicine, alerting healthcare professionals and patients that a new syringe is contained inside. Please note that the medicine is still the same and the formulation and storage conditions have not changed.
Here are some interesting videos showing and explaining their administration:
Administering a Somatuline Depot (Lanreotide) injection:
Administering a Sandostatin LAR (Octreotide) injection:
This link also provides guidance on the “new formulation” Octreotide. Click here.
My own experience only includes daily injections of Octreotide (Sep-Nov 2010) and Lanreotide (Dec 2010 onwards). I’ve also had continuous infusion of Octreotide in preparation for surgical or invasive procedures over the period 2010-2012 (i.e. crisis prevention). You can read about my Lanreotide experience by clicking here. If you are interested in what might be coming downstream, please see my blog entitled ‘Somatostatin Analogues and Delivery Systems in the Pipeline’.
Injection site granulomas (lumps)
The issue of ‘granulomas‘ or ‘injection site granulomas’ seems to figure in both drugs. Gluteal injection site granulomas are a very common finding on CT and plain radiographs. They occur as a result of subcutaneous (i.e. intra-lipomatous) rather than intramuscular injection of drugs, which cause localised fat necrosis, scar formation and dystrophic calcification. But no-one seems to know why they occur with somatostatin analogues.
Personally, I find that they are more conspicuous if the injection is done slightly too high which was my initial experience and they took months to fade. I opted to stand up for the first two injections and I attribute this decision for a slightly too high injection site. I now lie down which is actually recommended for the smaller and thinner patient. Although the lumps have reduced in size, I have not seen a new lump for some time indicating location might have been the cause. They sometimes show up on scans. This is not a new problem and has been highlighted for the last 10 years in academic papers. This particular paper is useful and the conclusion confirms this is not something that should worry patients too much. Read more here
Somatostatin Analogues and raised blood sugar levels
It is well documented that both Octreotide and Lanreotide can elevate blood glucose (sugar) levels. Read more in my article Diabetes – the NET Effect.