Targeted therapy for neuroendocrine cancer

Targeted therapy uses drugs to target specific molecules (such as proteins) on cancer cells or inside them. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells and limit harm to normal cells. Targeted therapy may also be called molecular targeted therapy.

Targeted therapy is sometimes used to treat some types of neuroendocrine tumour (NETs). If you have targeted therapy, your healthcare team will use what they know about the cancer and about your health to plan the drugs, doses and schedules.

You may have targeted therapy to:

• treat NETs that have spread within the organ where it started (locally advanced) or has spread to other organs (metastatic)
• treat NETs when surgery can’t be done

Targeted therapies are not usually used to treat neuroendocrine carcinomas (NECs) in Canada. But doctors may recommend certain targeted therapies based on where the NEC started or the genetic features of the NEC.

Targeted therapy drugs used for neuroendocrine cancer may not be covered by all provincial and territorial health plans. Talk to your doctor to learn more about the treatment being offered.

Different types of targeted therapy are used for NETs. The following are the most common types.

Tyrosine kinase inhibitors (TKIs) block chemicals called tyrosine kinases. These chemicals are part of the signalling process within cells. When this process is blocked, the cancer cells stop growing and dividing.

Sunitinib (Sutent) is a TKI used to treat advanced pancreatic neuroendocrine tumours (pNETs). It’s used when surgery can’t be done and the cancer is progressive, which means it continues to grow and spread. Sunitinib is taken daily as a pill by mouth (orally).

mTOR inhibitors block the mammalian target of rapamyin (mTOR). mTOR is a protein that controls cell growth and division. In some types of cancer, mTOR doesn’t work properly so cancer cells grow and divide out of control. mTOR inhibitors block the action of mTOR, which can stop the growth of some types of cancer.

Everolimus (Afinitor) is an mTOR inhibitor used to treat some types of NETs when they can’t be removed with surgery. It is used to treat:

• pancreatic NETs (pNETs) that are advanced and that have continued to grow and spread (progressive) over the last 12 months
• gastrointestinal NETs (GI NETs) that are advanced and non-functional (they make normal amounts of hormone and don’t cause symptoms)
• lung NETs that are advanced, progressive and non-functional

Everolimus is taken daily as a pill by mouth (orally).

Side effects of targeted therapy will depend mainly on the type of drug or combination of drugs, the dose, how it’s given and your overall health. Tell your healthcare team if you have side effects that you think are from targeted therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Sunitinib may cause these side effects:

• diarrhea
• fatigue
• nausea and vomiting
• taste changes
• indigestion
• sore mouth and throat
• high blood pressure (hypertension)
• abnormal liver function – may cause jaundice
• increased pancreatic enzyme levels – may cause pancreatitis

Everolimus may cause these side effects:

• sore mouth and throat
• skin problems, such as a rash
• fatigue
• high blood sugar
• low red blood count (anemia)
• weight loss
• diarrhea

Talk to your doctor or pharmacist about what side effects to expect.

Find out more about targeted therapy. To make the decisions that are right for you, ask your healthcare team questions about targeted therapy.

Details on specific drugs change regularly. Find out more about sources of drug information and where to get details on specific drugs.