What is appendix cancer?
Appendix cancer — also called appendiceal cancer — is a rare disease. It occurs when the cells in your appendix mutate (change) and grow out of control.
Your appendix is part of your digestive system. It’s a small tube-like pouch located on the lower right side of your abdomen, near the junction of your large intestine and small intestine. The function of your appendix is unknown. Some experts believe it has something to do with immune function. Others consider it a vestigial organ (one that is no longer useful from an evolutionary standpoint).
What are the different types of appendix tumors?
There are several benign and malignant tumors that can develop in the appendix, including carcinoid tumors, mucinous cystadenomas and appendiceal adenocarcinomas.
Approximately half of all appendix cancers are carcinoid tumors. They affect neuroendocrine cells, which receive signals from the nervous system and release hormones. In most cases, carcinoid tumors are slow-growing.
These noncancerous tumors form in the epithelium (lining) of the appendix. Mucinous cystadenomas won’t spread to other parts of your body as long as the appendix remains intact.
Adenocarcinoma cancers start in the glandular tissue that lines your organs. There are several categories of appendiceal adenocarcinoma, including:
- Mucinous adenocarcinoma. This is the second most common type of appendix cancer, just after carcinoid tumors. Mucinous adenocarcinomas start in the lining of your appendix and they release mucin — a component of mucus.
- Colonic-type adenocarcinoma. These tumors develop near the base of your appendix. They’re much like colorectal cancer tumors and cause many of the same symptoms.
- Signet ring cell adenocarcinoma. This aggressive tumor is rare, but it can occasionally form in the appendix. The cancer cells secrete and store large amounts of mucin. It’s called signet ring adenocarcinoma because the cancer cells have a signet ring appearance under a microscope.
Who does appendix cancer affect?
Appendix cancer can occur at any age, but it’s more likely to develop in people over 50. It’s also more common in women than men.
How common is appendix cancer?
This disease is very rare. In the United States, appendix cancer affects approximately 1 to 2 people out of every 1 million.
Symptoms and Causes
What are the signs of appendix cancer?
Sometimes people with appendix cancer don’t develop any symptoms. When warning signs occur, they can vary depending on the person. Appendix cancer symptoms may include:
- Appendicitis (inflammation or infection of the appendix).
- Abdominal pain.
- Pelvic pain.
- Fluid buildup in the abdomen (ascites).
- Changes in bowel function.
- Nausea and vomiting.
- Increase in waist size.
- Fertility problems.
How does someone get appendix cancer?
Appendix cancer starts when the cells in your appendix mutate and grow out of control. But experts don’t know what causes that process to begin with.
There are, however, certain risk factors associated with appendix cancer. These include:
- Smoking or using tobacco products**. **Tobacco use can increase your chances of all cancers, including appendix cancer.
- Medical history. Certain health conditions, including pernicious anemia and atrophic gastritis, may increase your risk for appendix cancer.
- Age. Your risk for appendix cancer increases as you grow older.
- Gender. Women are more likely than men to develop appendix cancer.
Is appendix cancer hereditary?
Experts don’t think there is a genetic or familial factor to appendix cancer. Research is ongoing in this area, but most health providers agree that appendix cancer is not hereditary.
Diagnosis and Tests
How is appendix cancer diagnosed?
People are often diagnosed with appendix cancer after an appendectomy (removal of the appendix) due to appendicitis. Sometimes imaging tests, such as X-rays or CT scans, reveal existing tumors.
What tests can diagnose appendix cancer?
If your healthcare provider suspects appendix cancer, then they may recommend more testing. These tests may include:
- Imaging tests. Your healthcare provider may recommend CT scans or MRI (magnetic resonance imaging). These imaging tests take pictures of the tissues inside your body. They can detect many different abnormalities, including tumors.
- Biopsy. During this procedure, your healthcare provider takes a tissue sample and sends it to a pathology lab for analysis. It can be difficult to take a biopsy of the appendix. So, if the cancer has potentially spread to another region, your healthcare provider will take a sample from that area.
- Laparoscopy. Your healthcare provider inserts a laparoscope — a long, slender fiber optic instrument — through an incision in your abdomen. A small camera captures images of your appendix and projects them onto a screen.
- Blood tests. If your biopsy comes back positive for appendix cancer, then your healthcare provider will recommend lab tests to check for protein levels. This can help determine the stage of the cancer.
Management and Treatment
How is appendix cancer treated?
There are several approaches when it comes to treating appendix cancer. Your healthcare provider will take several things into account before planning your treatment, including the size and stage of the tumor, your overall health and your personal preferences. Appendix cancer treatments may include:
- Surgery. Removal of the appendix may be enough to treat small tumors (less than 1 or 2 centimeters in size). However, larger tumors are usually more aggressive and require secondary surgery to remove more tissue. Possible procedures include hemicolectomy (removing part of your colon) and debulking surgery — a procedure in which the surgeon removes as much of the tumor as possible. Debulking also removes accumulated mucus, which can help ease bloating. In rare instances, your healthcare provider may recommend the removal of the peritoneum (the lining of the abdomen). However, this surgery has significant side effects and may not be suitable for everyone.
- Chemotherapy. This treatment uses drugs to kill cancer cells. The medications are either injected directly into your bloodstream or given in pill form.
- Hyperthermic intraperitoneal chemotherapy (HIPEC). This treatment involves heating chemotherapy drugs and circulating them inside your abdominal cavity. HIPEC is typically performed at the same time as surgery, while you’re still under general anesthesia. This approach is more intense than traditional chemotherapy.
- Targeted drug therapy. The goal of this treatment is to target cancer cells and limit damage to healthy cells. Specific drugs target certain genes or proteins that encourage cancer growth. Common drugs used in targeted therapy for appendix cancer include cetuximab, bevacizumab, ramucirumab and panitumumab.
What are the side effects of appendix cancer treatment?
There are several potential side effects that can occur during cancer treatment. The side effects that you experience can vary depending on which treatment you receive, the stage of cancer and your body’s healing capacity. Some of the most common cancer treatment side effects include:
Can I reduce my risk for appendix cancer?
There is no known way to prevent appendix cancer.
Outlook / Prognosis
What can I expect if I have appendix cancer?
How you respond to treatment for appendix cancer depends on several factors, including the type of appendiceal cancer you have, the location of the tumor and whether cancer has spread to other parts of your body. Your healthcare provider will discuss your options with you in detail.
Is appendix cancer curable?
Some types of appendix cancer are curable. The smaller the tumor, the more likely it is that treatment will be successful. Larger tumors are typically aggressive and may not respond as well to treatment.
What is the appendix cancer survival rate?
The five-year survival rate for low-grade appendix cancer is 67% to 97%. That means that 67% to 97% of people diagnosed with the disease are still alive five years later. However, the five-year survival rate for aggressive tumors can be much lower.
Keep in mind that survival rates can’t tell you how you’ll respond to treatment or how long you’ll live. These numbers represent the experiences of people who’ve been diagnosed with appendix cancer in the past. Because appendix cancer is a rare disease, survival rates for this type of cancer may not be precise. If you have questions about survival rates, talk to your healthcare provider.
When should I see my healthcare provider?
If you develop any appendix cancer symptoms, such as appendicitis, bloating or abdominal pain, call your healthcare provider right away.
If you’ve already been diagnosed with appendix cancer, you should call your provider if your symptoms change or worsen. They can find ways to ease your discomfort.
What questions should I ask my doctor?
Learning all you can about your condition can help you make informed decisions about your health. Here are some questions to consider asking your healthcare provider:
- What kind of appendix tumor do I have?
- What size is the tumor?
- What stage of appendix cancer do I have?
- Has the cancer spread to other parts of my body?
- What are my treatment options?
- When do I need to start treatment?
- Will I be able to work while undergoing cancer treatment?
- Are there additional resources or support groups available to me?
A note from Cleveland Clinic
An appendix cancer diagnosis can feel scary and uncertain. Talk to your healthcare provider about how you’re feeling. They can answer all of your questions and find resources to help you through this difficult time. Because appendix cancer is a rare disease, you may feel alone and isolated. Many people join support groups so they can talk with others who are going through the same thing.
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