Treatments for neuroendocrine carcinoma of unknown primary

Last medical review: October 2022

Neuroendocrine tumours start in the cells of the neuroendocrine system. Neuroendocrine carcinoma of unknown primary (neuroendocrine CUP) is usually found in the liver and may have started in the pancreas.

Doctors will look at the cancer cells to see the level of differentiation. Treatment decisions are based on if the cancer is poorly differentiated or well differentiated. Find out more about types of cancer of unknown primary, including the levels of differentiation.

Your healthcare team will suggest treatments based on your needs and work with you to develop a treatment plan.

Poorly differentiated neuroendocrine CUP

Combination chemotherapy is the main treatment for poorly differentiated neuroendocrine CUP.

It is usually treated with one of these combinations:

cisplatin and etoposide (Vepesid)
carboplatin and etoposide

Well-differentiated neuroendocrine CUP

Well-differentiated neuroendocrine CUP can be treated with chemotherapy, somatostatin analogues, targeted therapy or a combination of these treatments.

Chemotherapy drugs that may be offered are streptozocin (Zanosar) and 5-fluorouracil (also called 5-FU or fluorouracil).

Somatostatin analogues that may be offered are octreotide (Sandostatin) or lanreotide (Somatuline Autogel).

Targeted therapy drugs that may be offered are sunitinib (Sutent) or everolimus (Afinitor).

Find out more about drug therapy for neuroendocrine tumours.

Clinical trials

Talk to your doctor about clinical trials open to people with CUP in Canada. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.

If you can’t have or don’t want cancer treatment

You may want to consider a type of care to make you feel better without treating the cancer itself. This may be because the cancer treatments don't work anymore, they're not likely to improve your condition or they may cause side effects that are hard to cope with. There may also be other reasons why you can't have or don't want cancer treatment.

Talk to your healthcare team. They can help you choose care and treatment for advanced cancer.

Tien Le, MD, FRCSC, DABOG

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American Society of Clinical Oncology (ASCO). Cancer.net: Unknown Primary: Types of Treatment. 2021.
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PDQ Adult Treatment Editorial Board. Carcinoma of Unknown Primary Treatment (PDQ®) – Health Professional Version. Bethesda, MD: National Cancer Institute; 2018. https://www.cancer.gov/.
PDQ Adult Treatment Editorial Board. Carcinoma of Unknown Primary Treatment (PDQ®) – Patient Version. Bethesda, MD: National Cancer Institute; 2021. https://www.cancer.gov/.
National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Occult Primary (Cancer of Unknown Primary) Version 1.2023. 2022.
Yentz S, Bhave M, Cobain E, Baker L. Cancer of Unknown Primary. DeVita VT Jr., Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg's Cancer: Principles & Practice of Oncology. 11th ed. Philadelphia, PA: Wolters Kluwer; 2019: Kindle version, ch 108, https://read.amazon.ca/?asin=B0777JYQQC&language=en-CA.
Tan WW. Medscape Reference: Metastatic Cancer With Unknown Primary Site. 2022. https://www.medscape.com/oncology.

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