Neuroendocrine Tumor Symptoms

A woman feeling fatigued

A neuroendocrine tumor can cause a wide array of symptoms depending on the type of tumor and its location. These tumors affect the hormone-producing cells of the neuroendocrine system found throughout the body, causing those cells to send abnormally high amounts of hormones into the system. Symptoms vary depending on the types of cells that are affected and the hormones that are released.

Gastrointestinal carcinoids develop in the lining of the GI tract and affect a specialized cell that produces hormones for regulating digestive enzymes and peristalsis (the contraction of muscles that moves food along the digestive tract). These tumors tend to not produce symptoms in the cancer’s early stages. However, if the tumor reaches the liver or other organs and tissues in the body, it may produce symptoms such as:

  • Redness or a feeling of warmth in the neck or face
  • Fatigue
  • Shortness of breath
  • Wheezing
  • Quickened heartbeat
  • Diarrhea
  • Swelling in the feet or ankles
  • Pain or a feeling of fullness in the abdomen

Tumors that develop in the endocrine component of the pancreas are called islet cell tumors. Symptoms can vary depending on whether the tumor is cancerous or benign. Cancerous tumors can cause stomach ulcers, low blood sugar, a skin rash, a sore tongue or other symptoms depending on the excess hormones that are released. Benign tumors can cause abdominal pain, fatigue, fainting and unexplained weight gain.

What to do if you’re experiencing neuroendocrine cancer symptoms

Blood tests

If you suspect that you might have a neuroendocrine tumor, it’s important to not delay seeking a professional opinion, since these tumors can have a number of long-term effects on the body if left untreated. Your first step will likely be to reach out to your primary care provider, who can assess your condition through a physical examination and order any necessary diagnostic tests. Some of the tests used to diagnose a neuroendocrine tumor include:

      • Biopsy – This procedure—which involves removing a small portion of tissue from the patient’s body and then sending it to a laboratory for testing—is one of the most reliable methods for diagnosing a neuroendocrine tumor. Notably, if your physician suspects that you have a pheochromocytoma (a rare neuroendocrine tumor affecting the adrenal glands), he or she will likely order a biopsy only if it’s absolutely necessary to confirm your diagnosis, since performing a biopsy on this type of tumor could be life-threatening.
      • Blood/urine test – Because neuroendocrine tumors can cause the body to produce excess hormones, physicians will often order blood and/or urine testing to measure the patient’s hormone levels. For example, since neuroendocrine tumors can secrete serotonin, a physician might order a urine test to measure the level of hydroxyindoleacetic acid (5-HIAA), which is a breakdown product of serotonin.
      • Endoscopy – During an endoscopy, a clinician inserts a long, flexible tube (endoscope) through an opening in the patient’s body. The tube will have a light and a camera attached to it so that the practitioner can see inside. The spot where the tube is inserted will depend on where the suspected tumor is located. If a tumor is thought to be in the patient’s esophagus, for example, the physician will likely insert the tube through the patient’s mouth. But if the tumor is suspected to be in the patient’s colon, then the tube will likely be inserted through his or her anus.
      • Positron emission tomography (PET) scan – During a PET scan, the provider injects a small amount of a radioactive drug (tracer) into a vein in the patient’s arm. Once the injection is complete, the patient undergoes a scan to determine where the tracer has collected within his or her body.
      • Other imaging tests – Physicians often order ultrasounds and X-rays to create detailed images of a suspected neuroendocrine tumor.

If it turns out that you do have a neuroendocrine tumor, the results of these tests will also be helpful in determining how far the malignancy has progressed. For example, the results may show whether the tumor has spread (metastasized) to another area of your body.

Treatment for neuroendocrine tumors at Moffitt Cancer Center

In Moffitt Cancer Center’s Gastrointestinal Oncology Program, our neuroendocrine tumor team will assess a patient’s symptoms carefully and conduct a series of tests. If a diagnosis has been made, our multispecialty team will devise an individualized treatment plan and monitor the patient’s progress closely. We also offer innovative new treatments through our robust clinical trials program. 

If you’re concerned about possible neuroendocrine tumor symptoms or want to learn more about treatment strategies, contact Moffitt Cancer Center by calling 1-888-663-3488, or by filling out our online new patient registration form. We’re pleased to offer a faster initial turnaround than any other cancer hospital in the country, connecting new patients to a cancer expert within just one day.