Treatments for neuroendocrine carcinoma of unknown primary

Neuroendocrine carcinoma of unknown primary (CUP) is usually treated with chemotherapy or targeted therapy. Your healthcare team may suggest chemotherapy or targeted therapy based on your needs and work with you to develop a treatment plan.


Combination chemotherapy is the main treatment for neuroendocrine CUP. The drugs given will depend on if the cancer is poorly differentiated or well differentiated.

Poorly differentiated neuroendocrine CUP and small cell CUP are usually treated with either:

  • cisplatin (Platinol AQ) and etoposide (Vepesid, VP-16)
  • carboplatin (Paraplatin, Paraplatin AQ) and etoposide

Well differentiated neuroendocrine CUP may be treated with streptozocin (Zanosar) and 5-fluorouracil (Adrucil, 5-FU).

Targeted therapy

Targeted therapy may be offered to people with neuroendocrine carcinoma of unknown primary. The drugs used are:

  • sunitinib (Sutent)
  • everolimus (Afinitor)

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 rather than treat 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.

Clinical trials

You may be asked if you want to join a clinical trial for cancer of unknown primary. Find out more about clinical trials.

Expert review and references

  • Bhosale P, Shah A, Wei W, Varadhachary G, Johnson V, Shah V, and Kundra V . Carcinoid tumours: predicting the location of the primary neoplasm based on the sites of metastases. European Radiology. Springer; 2012.
  • Fizazi K, Greco FA, Pavlidis N, et al . Cancers of unknown primary site: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Annals of Oncology. Oxford University Press; 2011.
  • Greco FA & Hainsworth JD . Cancer of unknown primary site. DeVita VT Jr, Lawrence TS, & Rosenberg SA. Cancer: Principles & Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 113:1720-1737.
  • Hainsworth JD, Greco FA . Chemotherapy of carcinoma of unknown primary site. Perry MC, Doll DC, Freter CE. Perry's The Chemotherapy Source Book. 5th ed. Lippincott Williams Wilkins; 2012: Chapter 37.
  • Lisovsky M, Tafe LJ, Lefferts JA . Molecular diagnostics of metastatic malignancies. Tan D, Lynch, HT (eds.). Principles of Molecular Diagnostics and Personalized Cancer Medicine. Lippincott Williams & Wilkins; 2013: Chapter 42.
  • National Comprehensive Cancer Network. Occult Primary (Cancer of Unknown Primary [CUP]) (Version 3.2014).