What are Neuroendocrine Tumors? Symptoms, Causes, & Treatment

Neuroendocrine tumors are growths that develop from special cells throughout your body that make hormones and help coordinate important body functions. These cells, called neuroendocrine cells, act like a bridge between your nervous system and hormone-producing glands.

While the name might sound complex, think of these tumors as growths that can affect how your body produces and uses hormones. Most neuroendocrine tumors grow slowly and many people live full, active lives with proper treatment and monitoring.

What are neuroendocrine tumors?

Neuroendocrine tumors form when neuroendocrine cells begin growing abnormally. These special cells are scattered throughout your body, but they're most commonly found in your digestive system, lungs, and pancreas.

The tumors can be either benign (non-cancerous) or malignant (cancerous). Many of these tumors are functional, meaning they produce excess hormones that can cause noticeable symptoms. Others are non-functional and may not cause symptoms until they grow large enough to press on nearby organs.

These tumors are relatively uncommon, affecting about 6-7 people per 100,000 each year. However, doctors are diagnosing them more frequently now due to better imaging techniques and increased awareness.

What are the symptoms of neuroendocrine tumors?

Symptoms vary widely depending on where the tumor is located and whether it produces hormones. Many people experience general symptoms that can be easily mistaken for other conditions.

Here are the most common symptoms you might notice:

• Persistent abdominal pain or cramping that doesn't go away
• Changes in bowel movements, including diarrhea that lasts for weeks
• Unexplained weight loss without trying to lose weight
• Flushing episodes where your face and neck suddenly turn red and feel warm
• Wheezing or breathing difficulties that seem to come from nowhere
• Heart palpitations or irregular heartbeat
• Fatigue that doesn't improve with rest

Some people experience what doctors call "carcinoid syndrome," which happens when hormone-producing tumors release substances into your bloodstream. This can cause episodes of flushing, diarrhea, and breathing problems.

Less common symptoms might include skin rashes, blood sugar changes, or stomach ulcers. The key thing to remember is that symptoms often develop gradually and can be subtle at first.

What are the types of neuroendocrine tumors?

Doctors classify neuroendocrine tumors based on where they develop and how fast they grow. The location often determines what symptoms you might experience and what treatment options work best.

The most common types include:

• Gastroenteropancreatic (GEP) tumors that develop in your stomach, intestines, or pancreas
• Lung neuroendocrine tumors that form in your respiratory system
• Pancreatic neuroendocrine tumors, including insulinomas and gastrinomas
• Carcinoid tumors, which most often occur in your small intestine or appendix

Doctors also grade these tumors from G1 to G3 based on how quickly the cells are dividing. G1 tumors grow slowly, G2 tumors grow at a moderate pace, and G3 tumors grow more rapidly and require more aggressive treatment.

Your healthcare team will determine the specific type and grade through various tests, which helps them create the most effective treatment plan for your situation.

What causes neuroendocrine tumors?

The exact cause of most neuroendocrine tumors remains unknown, but researchers believe they develop when neuroendocrine cells undergo genetic changes that cause them to grow abnormally. These changes usually happen randomly over time.

Several factors may contribute to their development:

• Age-related cellular changes, as these tumors are more common in people over 50
• Inherited genetic syndromes like Multiple Endocrine Neoplasia (MEN) syndromes
• Family history of neuroendocrine tumors or related conditions
• Certain medical conditions that affect stomach acid production

In rare cases, people inherit genetic mutations that significantly increase their risk. These inherited syndromes account for only about 5-10% of all neuroendocrine tumors.

Most importantly, these tumors are not caused by lifestyle choices like diet, smoking, or stress. You haven't done anything to cause this condition, and there's no reason to blame yourself if you're dealing with a neuroendocrine tumor.

When to see a doctor for neuroendocrine tumors?

You should contact your healthcare provider if you experience persistent symptoms that last more than a few weeks, especially if they're affecting your daily life. While these symptoms can have many causes, it's always better to get them checked out.

Seek medical attention promptly if you notice:

• Severe abdominal pain that doesn't improve with over-the-counter medications
• Persistent diarrhea lasting more than two weeks
• Unexplained weight loss of more than 10 pounds
• Frequent flushing episodes combined with other symptoms
• Difficulty breathing or wheezing that's getting worse

Don't wait if you're experiencing severe symptoms or if multiple symptoms are occurring together. Your doctor can help determine whether further testing is needed.

Remember, many conditions can cause similar symptoms, so try not to worry too much before speaking with a healthcare professional. Early evaluation often leads to better outcomes when treatment is needed.

What are the risk factors for neuroendocrine tumors?

Several factors may increase your likelihood of developing a neuroendocrine tumor, though having risk factors doesn't mean you'll definitely develop one. Understanding these factors can help you and your doctor stay alert to potential symptoms.

The main risk factors include:

• Age over 50, when cellular changes become more common
• Family history of neuroendocrine tumors or related genetic syndromes
• Inherited conditions like Multiple Endocrine Neoplasia syndromes
• Certain stomach conditions that reduce acid production
• Being African American, which slightly increases risk for some types

Some rare genetic syndromes significantly increase risk, including von Hippel-Lindau disease and neurofibromatosis type 1. These conditions run in families and usually involve multiple types of tumors.

Having one or more risk factors doesn't mean you'll develop a neuroendocrine tumor. Many people with risk factors never develop these tumors, while others with no known risk factors do.

What are the possible complications of neuroendocrine tumors?

Most neuroendocrine tumors grow slowly and cause manageable complications, especially when caught early. However, some complications can develop if tumors aren't treated or if they produce excess hormones.

Common complications you might experience include:

• Carcinoid syndrome from hormone-producing tumors causing flushing and diarrhea
• Bowel obstruction if tumors in your intestines grow large enough
• Heart valve problems from long-term carcinoid syndrome
• Blood sugar imbalances from pancreatic tumors
• Stomach ulcers from gastrin-producing tumors

Rare but serious complications can include carcinoid crisis, which involves severe flushing, blood pressure changes, and breathing difficulties. This typically happens only with advanced hormone-producing tumors.

The good news is that modern treatments can prevent or manage most complications effectively. Your healthcare team will monitor you closely and adjust treatment as needed to minimize any complications.

How can neuroendocrine tumors be prevented?

Unfortunately, there's no proven way to prevent most neuroendocrine tumors since they usually develop due to random genetic changes. However, you can take steps to support your overall health and catch any problems early.

Here's what you can do:

• Maintain regular checkups with your healthcare provider
• Report any persistent or unusual symptoms promptly
• Follow screening recommendations if you have a family history
• Consider genetic counseling if you have inherited risk factors
• Live a generally healthy lifestyle with good nutrition and regular exercise

If you have a known genetic syndrome that increases your risk, your doctor may recommend specific screening tests or more frequent monitoring. This proactive approach can help catch tumors early when they're most treatable.

While you can't prevent these tumors entirely, staying aware of your body and maintaining open communication with your healthcare team gives you the best chance for early detection and successful treatment.

How are neuroendocrine tumors diagnosed?

Diagnosing neuroendocrine tumors often requires several different tests because symptoms can be similar to many other conditions. Your doctor will start with a thorough medical history and physical examination to understand your symptoms.

The diagnostic process typically includes:

• Blood tests to check hormone levels and tumor markers
• Urine tests to measure hormone breakdown products
• CT or MRI scans to locate and measure tumors
• Specialized scans like octreotide scans that target neuroendocrine cells
• Endoscopy procedures to examine your digestive tract
• Biopsy to confirm the diagnosis and determine tumor grade

Your doctor might order specific hormone tests based on your symptoms. For example, if you're having blood sugar problems, they'll check insulin levels. If you're experiencing flushing and diarrhea, they'll test for substances associated with carcinoid syndrome.

The entire diagnostic process can take several weeks or even months, which can feel frustrating. However, getting an accurate diagnosis is crucial for developing the most effective treatment plan for your specific situation.

What is the treatment for neuroendocrine tumors?

Treatment for neuroendocrine tumors depends on several factors including the tumor's location, size, grade, and whether it's producing hormones. Many people do very well with treatment, and some tumors can be completely cured.

Your treatment plan might include:

• Surgery to remove the tumor, which is often the preferred treatment for localized tumors
• Somatostatin analogs to control hormone production and slow tumor growth
• Targeted therapy drugs that specifically attack tumor cells
• Chemotherapy for more aggressive or widespread tumors
• Radiation therapy to shrink tumors or relieve symptoms
• Liver-directed treatments if tumors have spread to the liver

For hormone-producing tumors, your doctor will focus on controlling symptoms while treating the tumor itself. This might involve medications to manage diarrhea, flushing, or blood sugar problems.

Many people with slow-growing tumors can be monitored with regular scans and blood tests without immediate treatment. This approach, called active surveillance, allows you to avoid treatment side effects while ensuring the tumor isn't growing or changing.

How to manage neuroendocrine tumors at home?

Managing life with a neuroendocrine tumor involves both medical treatment and practical daily strategies. Many people find they can maintain their quality of life with some adjustments and self-care approaches.

Here are helpful strategies for daily management:

• Keep a symptom diary to track patterns and triggers
• Eat smaller, more frequent meals to help with digestive symptoms
• Stay hydrated, especially if you're experiencing diarrhea
• Avoid foods and drinks that trigger flushing episodes
• Practice stress management techniques like deep breathing or meditation
• Get adequate rest and maintain a regular sleep schedule

If you're dealing with carcinoid syndrome, you might need to avoid certain foods like aged cheeses, alcohol, or spicy foods that can trigger flushing episodes. Your healthcare team can provide specific dietary guidance.

Stay connected with support groups or counseling services if you're feeling overwhelmed. Many people find it helpful to talk with others who understand what they're going through.

How should you prepare for your doctor appointment?

Preparing for your appointment can help you make the most of your time with your healthcare provider and ensure you get all the information you need. Good preparation also helps your doctor better understand your situation.

Before your appointment:

• List all your symptoms, including when they started and how often they occur
• Bring all current medications, including supplements and over-the-counter drugs
• Prepare questions about your diagnosis, treatment options, and prognosis
• Gather relevant medical records from other doctors
• Consider bringing a family member or friend for support and to help remember information

Write down specific questions you want to ask, such as what type of tumor you have, what treatment options are available, and what to expect moving forward. Don't hesitate to ask for clarification if something doesn't make sense.

Remember that this is your healthcare, and you have the right to understand your condition fully. A good doctor will take time to answer your questions and help you feel comfortable with your treatment plan.

What's the key takeaway about neuroendocrine tumors?

Neuroendocrine tumors are manageable conditions that affect hormone-producing cells throughout your body. While receiving this diagnosis can feel overwhelming, most people with these tumors live full, active lives with proper treatment and monitoring.

The most important things to remember are that these tumors often grow slowly, many treatment options are available, and early detection usually leads to better outcomes. Your healthcare team will work with you to develop a personalized treatment plan that fits your specific situation.

Don't hesitate to ask questions, seek second opinions if needed, and lean on your support system during this journey. With today's advanced treatments and monitoring techniques, the outlook for people with neuroendocrine tumors continues to improve.