Appendix Cancer

The appendix is a pouch-like tube that is attached to the cecum (the first section of the large intestine or colon). The appendix averages 10 centimeters (cm) in length and is considered part of the gastrointestinal (GI) tract. Generally thought to have no significant function in the body, the appendix may be a part of the lymphatic, exocrine, or endocrine systems.

Appendix cancer occurs when cells in the appendix become abnormal and multiply without control. These cells form a growth of tissue, called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). Another name for this type of cancer is appendiceal cancer.

Types of appendix tumors

There are different types of tumors that can start in the appendix:

Carcinoid tumor. A carcinoid tumor starts in the hormone-producing cells that are normally present in small amounts in almost every organ in the body. A carcinoid tumor starts primarily in either the GI tract or lungs, but it also may occur in the pancreas, a man’s testicles, or a woman’s ovaries. An appendix carcinoid tumor most often occurs at the tip of the appendix. Approximately 66% of all appendix tumors are carcinoid tumors. This type of cancer usually causes no symptoms until it has spread to other organs and often goes unnoticed until it is found during an examination or procedure performed for another reason. An appendix carcinoid tumor that remains confined to the area where it started has a high chance of successful treatment with surgery. Learn more about carcinoid tumors.

Mucinous cystadenocarcinoma. Mucinous cystadenocarcinoma is the most common non-carcinoid appendix tumor and accounts for about 20% of appendix cancer cases. This type of tumor produces a jelly-like substance called mucin that can fill the abdominal cavity and can cause abdominal pain, bloating, and changes in bowel function if the tumor breaks through the appendix or grows in the abdomen.

Colonic-type adenocarcinoma. Colonic-type adenocarcinoma accounts for about 10% of appendix tumors and usually occurs at the base of the appendix. This type of tumor looks and behaves like the most common type of colorectal cancer. It often goes unnoticed, and a diagnosis is frequently made during or after surgery for appendicitis (inflammation of the appendix that can cause abdominal pain or swelling, loss of appetite, nausea, vomiting, constipation or diarrhea, inability to pass gas, or a low fever that begins after other symptoms).

Signet-ring cell adenocarcinoma. Signet-ring cell adenocarcinoma (so called because, under the microscope, the cell looks like it has a signet ring inside it) is very rare and considered to be more aggressive and more difficult to treat than other types of adenocarcinomas. This type of tumor usually occurs in the stomach or colon, and it can cause appendicitis when it develops in the appendix.

Paraganglioma. Paraganglioma is a rare tumor that develops from cells of the paraganglia, a collection of cells that come from nerve tissue that persist in small deposits after fetal (pre-birth) development, and is found near the adrenal glands and some blood vessels and nerves. This type of tumor is usually considered benign and is often successfully treated with the complete surgical removal of the tumor. Paraganglioma is very rare outside of the head and neck region.

Symptoms and Signs

People with appendix cancer may experience the following symptoms or signs. Sometimes, people with appendix cancer 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.

• Appendicitis
• Ascites (fluid in the abdomen)
• Bloating
• Pain in the abdomen or pelvis area
• Increased girth (size of the waistline), with or without a protrusion of the navel (bellybutton)
• Changes in bowel function
• Infertility (the inability to have a child)

Stages 

Staging for carcinoid tumors of the appendix

Tumor. Using the TNM system, the "T" plus a letter or number (0 to 4) is used to describe the size and location of the tumor. Some stages are also divided into smaller groups that help describe the tumor in even more detail. Specific tumor stage information is listed below.

TX: The primary tumor cannot be evaluated.

T0: There is no evidence of cancer in the appendix.

T1: The tumor is 2 centimeters (cm) or smaller.

T1a: The tumor is 1 cm or smaller.

T1b: The tumor is larger than 1 cm but no larger than 2 cm.

T2: The tumor is larger than 2 cm but smaller than 4 cm, or it has extended into the large intestine.

T3: The tumor is larger than 4 cm or has extended into the small intestine.

T4: The tumor directly invades the abdominal wall or other nearby organs.

Node. The "N" in the TNM system stands for lymph nodes. The lymph nodes are tiny, bean-shaped organs that are located throughout the body that help the body fight infections as part of the body's immune system. There are regional lymph nodes (lymph nodes near the appendix). All others are distant lymph nodes (lymph nodes found in other parts of the body).

NX: The regional lymph nodes cannot be evaluated because of a lack of information.

N0: The cancer has not spread to the regional lymph nodes.

N1: The cancer has spread to the regional lymph nodes.

Distant metastasis. The "M" in the TNM system describes cancer that has spread to other parts of the body (such as the liver or lungs).

M0: The cancer has not spread to other parts of the body.

M1: The cancer has spread to other parts of the body.

Cancer stage grouping for carcinoid tumors of the appendix

Doctors assign the stage of the cancer by combining the T, N, and M classifications.

Stage I: The cancer is 2 cm or smaller and has not spread to the regional lymph nodes or to other parts of the body (T1, N0, M0).

Stage II: The cancer is larger than 2 cm and has or has not extended into the large or small intestine but has not spread to the regional lymph nodes or to other parts of the body (T2 or T3, N0, M0).

Stage III: Stage III cancer describes either of these situations:

• The cancer has directly invaded the abdominal wall or has spread to other nearby organs but has not spread to the regional lymph nodes or to other parts of the body (T4, N0, M0).
• The cancer is any size and may have spread to organs or structures near the appendix and has spread to the regional lymph nodes but not to distant parts of the body (T, N1, M0).

Stage IV: The cancer has spread to distant parts of the body, no matter the size of the tumor or whether it has spread to the regional lymph nodes (any T, any N, M1).

Staging for carcinomas of the appendix

Appendiceal carcinomas are also staged according to the TNM staging system.

Tumor. Using the TNM system, the "T" plus a letter or number (0 to 4) is used to describe the size and location of the tumor. Some stages are also divided into smaller groups that help describe the tumor in even more detail. Specific tumor stage information is listed below.

TX: The primary tumor cannot be evaluated.

T0: There is no evidence of cancer in the appendix.

Tis: This refers to carcinoma in situ (also called cancer in situ). Cancer cells are found only in the first layers lining the inside of the appendix.

T1: The tumor has invaded the submucosa (the next deepest layer of the appendix).

T2: The tumor has invaded the muscularis propria (the third layer of the appendix).

T3: The tumor has grown through the muscularis propria and into the subserosa (a thin layer of connective tissue) of the appendix or into the mesoappendix (an area of fatty tissue next to the appendix that provides the blood supply).

T4: The tumor has grown through the visceral peritoneum (the lining of abdominal cavity) or has invaded other organs.

T4a: The tumor has invaded the visceral peritoneum.

T4b: The tumor has invaded other organs or structures, such as the colon or rectum.

Node. The "N" in the TNM system stands for lymph nodes. The lymph nodes are tiny, bean-shaped organs that are located throughout the body that help the body fight infections as part of the body's immune system. There are regional lymph nodes (lymph nodes near the appendix). All others are distant lymph nodes (lymph nodes found in other parts of the body).

NX: The regional lymph nodes cannot be evaluated because of a lack of information.

N0: There is no regional lymph node metastasis.

N1: Cancer has spread to one to three regional lymph nodes.

N2: Cancer has spread to four or more regional lymph nodes.

Distant metastasis. The "M" in the TNM system describes cancer that has spread to other parts of the body (such as the liver or lungs).

MX: Distant metastasis cannot be evaluated.

M0: The cancer has not metastasized.

M1a: There is intraperitoneal metastasis (the cancer has spread to organs or structures within the abdominal area).

M1b: There is nonperitoneal distant metastasis (the cancer has spread outside of the abdominal cavity).

Tumor grade. Doctors may also use the term "grade," which describes how much the tumor appears like normal tissue under a microscope. The grade of a cancer can help the doctor predict how quickly the cancer might grow. In cancer that resembles normal tissue, doctors can clearly see different types of cells grouped together (called well differentiated). In a higher-grade cancer, cancer cells usually look less like normal cells, or "wilder" (called poorly differentiated or undifferentiated). In general, a patient with a more differentiated tumor has a lower grade and a better prognosis.

GX: The tumor grade cannot be identified.

G1: The tumor cells are well-differentiated.

G2: The tumor cells are moderately differentiated.

G3: The tumor cells are poorly differentiated.

G4: The tumor cells are undifferentiated.

Cancer stage grouping for carcinomas of the appendix

Doctors assign the stage of the cancer by combining the T, N, and M classifications. In describing Stage IV, doctors also consider the grade (G).

Stage 0: This refers to cancer in situ. The cancer is found in only one place and has not spread (Tis, N0, M0).

Stage I: The cancer has spread to inner layers of appendix tissue but has not spread to the regional lymph nodes or to other parts of the body (T1 or T2, N0, M0).

Stage IIA: The cancer has grown into the connective or fatty tissue next to the appendix but has not spread to the regional lymph nodes or to other parts of the body (T3, N0, M0).

Stage IIB: The cancer has grown through the lining of the appendix but has not spread to the regional lymph nodes or to other parts of the body (T4a, N0, M0).

Stage IIC: The tumor has grown into other organs, such as the colon or rectum, but has not spread to the regional lymph nodes or to other parts of the body (T4b, N0, M0).

Stage IIIA: The cancer has spread to inner layers of appendix tissue and to one to three regional lymph nodes but has not spread to other parts of the body (T1 or T2, N1, M0).

Stage IIIB: The cancer has grown into nearby tissue of the appendix or through the lining of the appendix and to one to three regional lymph nodes but has not spread to other areas of the body (T3 or T4, N1, M0).

Stage IIIC: This stage describes a cancer that has spread to four or more regional lymph nodes but not to other areas of the body (any T, N2, M0).

Stage IVA: This stage describes a cancer that has spread to other areas in the abdomen but not to the regional lymph nodes; the cancer cells are well differentiated (any T, N0, M1a, G1).

Stage IVB: Stage IVB describes any of these three situations;

• The cancer has spread to other areas in the abdomen but not to the regional lymph nodes; the cells are moderately or poorly differentiated (any T, N0, M1a, G2 or G3).
• The cancer has spread to other areas in the abdomen and to one to three regional lymph nodes; the cells may be any grade (any T, N1, M1a, any G).
• The cancer has spread to other areas in the abdomen and to four or more regional lymph nodes; the cells may be any grade (any T, N2, M1a, any G).

Stage IVC: The cancer has spread outside the abdominal area to distant parts of the body, such as the lungs (any T, any N, M1b, any G).

Treatment

Surgery

Surgery is the removal of the tumor and surrounding tissue during an operation. It is the most common treatment for appendix cancer. Most often, appendix cancer is low-grade (see Stages and Grades) and, therefore, slow-growing. Often it can be successfully treated with surgery alone. A surgical oncologist is a doctor who specializes in treating cancer using surgery. Types of surgeries for appendix cancer include:

Appendectomy. An appendectomy is the surgical removal of the appendix. It is usually the only treatment needed for an appendix tumor smaller than 1.5 centimeters (cm).

In cases when appendix cancer is discovered unexpectedly after an appendectomy was performed for what was originally thought to have been appendicitis, a second operation to remove more tissue (using surgical techniques described below) is often recommended.

Hemicolectomy. For a tumor larger than 2 cm, a hemicolectomy may be recommended. This is the removal of a portion of the colon next to the appendix; removal of nearby blood vessels and lymph nodes is often done at the same time. A right hemicolectomy is surgery performed on the right side of the colon. Even though a large amount of the large intestine is removed, the operation usually does not result in the need for a colostomy or stoma (an opening in the abdomen through which the bowel contents are emptied into a bag).

Debulking surgery. For later stage appendix cancer, debulking (or cytoreduction) surgery may be performed. In this surgery, the doctor removes as much of the tumor “bulk” as possible, which could benefit the patient even though it will not remove every cancer cell from the body. Sometimes, debulking surgery will be followed with chemotherapy (see below) to destroy any remaining cancer cells.

In cases when the tumor produces mucous, much of the bulk of the abnormal tissue often is not cancer but is due to accumulation of the mucous. The mucous looks like jelly, and this condition is often referred to as “jelly belly.” Removing the mucous from the abdomen can often relieve a patient’s symptoms of bloating.

Removal of the peritoneum. There is some controversy about the extent of surgery that is necessary in patients with slow-growing, low-grade cancer that has spread beyond the colon to involve other areas of the abdomen. Some surgeons recommend aggressive surgery that includes the removal of the peritoneum (the lining of the abdomen) to remove as much of the cancer as possible. This type of surgery is also called a peritonectomy.

In patients with a very slow-growing tumor, such surgery can be effective in removing the majority of the cancer cells. This can benefit the patient by reducing the amount of cancer, even if it does not remove every cancer cell. However, it is a difficult operation that can have significant side effects. The doctor will consider many different factors, such as the patient’s age and overall health, before recommending this extensive surgery. Patients should talk with a specialist with expertise in this type of procedure beforehand.  

Chemotherapy

Chemotherapy is the use of drugs to kill cancer cells, usually by stopping the cancer cells’ ability to grow and divide. Chemotherapy is given by a medical oncologist, a doctor who specializes in treating cancer with medication. For appendix cancer, chemotherapy is most often used soon after surgery when cancer is found outside of the appendix region. There are different types of chemotherapy, depending on how the drugs are delivered to the body:

Local/intraperitoneal chemotherapy. For local chemotherapy, the medication delivery is focused on one area or section of the body. This is the most common type of chemotherapy used in the treatment of appendix cancer; more specifically, it is called intraperitoneal chemotherapy, which is chemotherapy that is given directly into the abdominal cavity. Typically, the surgeon will try to remove as much of the tumor as possible (debulking surgery, see above) and then insert a tube in the abdomen through which chemotherapy can be given after the operation. In some cases, the chemotherapy is warmed beyond body temperature to increase its ability to penetrate the tissue that may be lined with tumor cells; this is called hyperthermic (or heated) intraperitoneal chemotherapy. Once chemotherapy is completed, the tube is removed, generally without the need for another operation.

Systemic chemotherapy. This type of chemotherapy is delivered through the bloodstream to reach cancer cells throughout the body. This can be done using an intravenous (IV) tube (a tube inserted into a person’s vein). Some people may receive this type of chemotherapy in their doctor’s office or outpatient clinic; others may go to the hospital. A chemotherapy regimen (schedule) usually consists of a specific number of cycles given over a set period of time. A patient may receive one drug at a time or combinations of different drugs at the same time. Specific drugs given in systemic chemotherapy are similar to those for colorectal cancer and can include fluorouracil (5-FU, Adrucil), leucovorin (Wellcovorin), capecitabine (Xeloda), irinotecan (Camptosar), oxaliplatin (Eloxatin), bevacizumab (Avastin), and cetuximab (Erbitux).

The side effects of chemotherapy depend on the individual and the dose used, but they can include fatigue, risk of infection, nausea and vomiting, hair loss, loss of appetite, and diarrhea. These side effects usually go away when treatment is finished.

Learn more about chemotherapy and preparing for treatment. The medications used to treat cancer are continually being evaluated. Talking with your doctor is often the best way to learn about the medications prescribed for you, their purpose, and their potential side effects or interactions with other medications. Learn more about your prescriptions by using searchable drug databases.

Radiation therapy

Radiation therapy is the use of high-energy x-rays or other particles to kill cancer cells. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. A radiation therapy regimen (schedule) usually consists of a specific number of treatments given over a set period of time.

Radiation therapy is rarely used in the treatment of appendix cancer. In certain cases, a form of radiation called P32 may be recommended. In this procedure, radioactive phosphorus is dissolved in a liquid and placed inside the body after surgery through a tube inserted in the abdomen (see above). P32 delivers strong radiation therapy to a specific area. Because the radioactivity disappears quickly (within a few hours), there is no need to remove the substance from the abdomen after treatment.

Side effects from radiation therapy may include fatigue, mild skin reactions, upset stomach, and loose bowel movements. Most side effects go away soon after treatment is finished.

Getting care for symptoms and side effects 

Cancer and its treatment often cause side effects. In addition to treatment to slow, stop, or eliminate the cancer, an important part of cancer care is relieving a person’s symptoms and side effects. This approach is called palliative or supportive care, and it includes supporting the patient with his or her physical, emotional, and social needs.

Palliative care can help a person at any stage of illness. People often receive treatment for the cancer and treatment to ease side effects at the same time. In fact, patients who receive both often have less severe symptoms, better quality of life, and report they are more satisfied with treatment.

Palliative treatments vary widely and often include medication, nutritional changes, relaxation techniques, and other therapies. You may also receive palliative treatments similar to those meant to eliminate the cancer, such as chemotherapy, surgery, and radiation therapy. Talk with your doctor about the goals of each treatment in your treatment plan.

Before treatment begins, talk with your health care team about the possible side effects of your specific treatment plan and supportive care options. And during and after treatment, be sure to tell your doctor or another health care team member if you are experiencing a problem so it is addressed as quickly as possible. Learn more about palliative care.   

Recurrent appendix cancer

A remission is when cancer cannot be detected in the body and there are no symptoms. This may also be called “no evidence of disease” or NED. 

A remission can be temporary or permanent. This uncertainty leads to many survivors feeling worried or anxious that the cancer will come back. While many remissions are permanent, it’s important to talk with your doctor about the possibility of the cancer returning. Understanding the risk of recurrence and the treatment options may help you feel more prepared if the cancer does return. Learn more about coping with the fear of recurrence. 

If the cancer does return after the original treatment, it is called recurrent cancer. It may come back in the same place (called a local recurrence), nearby (regional recurrence), or in another place (distant recurrence).

When this occurs, a cycle of testing will begin again to learn as much as possible about the recurrence, including whether the cancer’s stage has changed. After testing is done, you and your doctor will talk about your treatment options. Often the treatment plan will include the therapies described above (such as surgery, chemotherapy, and radiation therapy) but they may be used in a different combination or given at a different pace. Your doctor may also suggest clinical trials that are studying new ways to treat this type of recurrent cancer.

People with recurrent cancer often experience emotions such as disbelief or fear. Patients are encouraged to talk with their health care team about these feelings and ask about support services to help them cope. Learn more about dealing with cancer recurrence.

Metastatic appendix cancer

If cancer has spread to another location in the body, it is called metastatic cancer.

Patients with this diagnosis are encouraged to talk with doctors who are experienced in treating this stage of cancer, because there can be different opinions about the best treatment plan. Learn more about seeking a second opinion before starting treatment, so you are comfortable with the treatment plan chosen. This discussion may include clinical trials.