Medication Used to Treat GEP-NETs

There are a lot of medication options for GEP-NETs, depending on where the tumour is and what symptoms it’s causing.1,2

They might be used as well as, or instead of surgery or radiotherapy. Some of the drugs used include:

Somatostatin analogues (known as SSAs)
Immunotherapy like interferon-α
Chemotherapy
Other drug therapies e.g. angiogenesis inhibitors (known as AGIs)

Somatostatin analogues (SSAs)

SSAs are the most common GEP-NET drug therapy.3

Somatostatin is a substance that is produced naturally by the body. It helps regulate the production and release of hormones.4

Somatostatin analogues are man-made versions of this substance. They act in the same way as your natural somatostatin to help control the extra hormones released by a GEP-NET. This helps to control your symptoms.

SSAs also help to stabilise the growth of the GEP-NET and slow it down.3

The two main SSAs are lanreotide and octreotide.3,4

As with all medications, these treatments can cause side effects. The most common are feeling sick (nausea), bloating and diarrhoea.4 Your doctor will discuss potential side effects of your drug with you, and want to know if you are experiencing any side effects as your treatment starts.

There are two kinds of SSAs: short-acting and long-acting.3 Short-acting SSAs are used to bring symptoms under control quickly, and to see how you get on with this type of drug. Long-acting SSAs are taken as an injection every 4 weeks or so, and you would use them for ongoing treatment of a GEP-NET.3

Interferon-α3

Interferon alpha is used to help slow down the growth of a GEP-NET. It is no longer used very often, as a lot of people get side effects from interferon-α. However, it might be offered if you don’t get on with SSAs, or in combination with another medication.

Chemotherapy3,5

Chemotherapy is a term used to mean all the drugs and combinations of drugs that are commonly given to treat cancers. Chemotherapy drugs might be added to your treatment plan if:

Surgery and/or other medications haven’t worked well enough
The GEP-NET is growing fast
Your GEP-NET has spread (metastasised)

Angiogenesis inhibitors (AGIs)

Angiogenesis (anjee-oh-jenner-sis) is the process of creating new blood vessels which are vital for the growth of a tumour.6,7

AGIs help to block this process, so the tumour can’t get a good blood supply and can’t grow.6-8

Within the AGI group of drugs there is a subsection known as tyrosine kinase inhibitors (TKIs).6-8 You may hear your medications described as an AGI or a TKI, but they all act in a similar way to help shrink the tumour. Most AGIs used to treat GEP-NETs are given as tablets you take at home every day. 7,9-11

The most commonly used AGIs include:7,8

Bevacizumab
Sunitinib (a TKI)
Sorafenib (a TKI)

REFERENCES:

NHS. Neuroendocrine tumours. Available at:
https://www.nhs.uk/conditions/neuroendocrine-tumours Last accessed September 2020.
Macmillan. Treatment for NETs. Available at:
https://www.macmillan.org.uk/cancer-information-and-support/neuroendocrine-tumours-nets#treatment_for_neuroendocrine_tumours_nets Last accessed September 2020.
Díez M, Teulé A, Salazar R. Gastroenteropancreatic neuroendocrine tumors: diagnosis and treatment. Ann Gastroenterol 2013;26(1):29-36. Available at:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3959515/ Last accessed September 2020.
CRUK. What are somatostatin analogues? Available at:
https://www.cancerresearchuk.org/about-cancer/neuroendocrine-tumours-nets/treatment/somatostatin-analogues/what-are Last accessed September 2020.
CRUK. Having chemotherapy. Available at:
https://www.cancerresearchuk.org/about-cancer/neuroendocrine-tumours-nets/treatment/chemotherapy/having Last accessed September 2020.
NIH: National Cancer Institute. Angiogenesis inhibitors. Available at:
https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/angiogenesis-inhibitors-fact-sheet Last accessed September 2020.
Capozzi et al. Antiangiogenic Therapy in Pancreatic Neuroendocrine Tumours. Anticancer Research 2016. 36:5025-5030.
Carrasco P, Zuazo-Gaztelu I, Casanovas O. Sprouting strategies and dead ends in antiangiogenic targeting of NETs. J Molecular Endocrinology 2017. 59;1:R77-R91.
CRUK. Bevacizumab. Available at:
https://www.cancerresearchuk.org/about-cancer/cancer-in-general/treatment/cancer-drugs/drugs/bevacizumab
CRUK. Sunitinib. Available at:
https://www.cancerresearchuk.org/about-cancer/cancer-in-general/treatment/cancer-drugs/drugs/sunitinib.
EMC. Nevaxar^® Summary of Product Characteristics. Available at:
https://www.medicines.org.uk/emc/product/226#. Last accessed September 2020.