People with a neuroendocrine tumor may experience the following symptoms or signs. Sometimes, people with a neuroendocrine tumor do not show any of these symptoms. Or, these symptoms may be caused by a medical condition that is not cancer. If you are concerned about a symptom or sign on this list, please talk with your doctor.

Pheochromocytoma

• Hypertension (high blood pressure)
• Anxiety attacks
• Fever
• Headaches
• Sweating
• Nausea
• Vomiting
• Clammy skin
• Rapid pulse
• Heart palpitations

Merkel cell cancer

• Painless, firm, shiny lumps on the skin that can be red, pink, or blue in color

Neuroendocrine carcinoma

• Hyperglycemia (a high level of a sugar called glucose in the blood, which causes frequent urination, increased thirst, and increased hunger)
• Hypoglycemia (a low level of glucose in the blood, which causes fatigue, nervousness and shakiness, dizziness or light-headedness, sweating, seizures, and fainting)
• Diarrhea
• Persistent pain in a specific area
• Loss of appetite/weight loss
• Persistent cough or hoarseness
• Thickening or lump in any part of the body
• Changes in bowel or bladder habits
• Unexplained weight gain or loss
• Jaundice (yellowing of the skin and whites of the eyes)
• Unusual bleeding or discharge
• Persistent fever or night sweats
• Headache
• Anxiety
• Gastric ulcer disease
• Skin rash

Some people also experience nutritional deficiencies (such as niacin and protein deficiency) before a diagnosis, while others have this symptom later.

Your doctor will ask you questions about the symptoms you are experiencing to help find out the cause of the problem, called a diagnosis [2]. This may include how long you’ve been experiencing the symptom(s) and how often.

If cancer is diagnosed, relieving symptoms and side effects remains an important part of cancer care and treatment. This may also be called symptom management, palliative care, or supportive care. Be sure to talk with your health care team about symptoms you experience, including any new symptoms or a change in symptoms.