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Appendix Cancer

Appendix cancer is rare, occurring in about 1,000 people in the United States each year. In those cases, abnormal cells grow wildly in your appendix (a small pouch connected to your colon with no known purpose) and form a tumor. Tumors can be either benign (non-cancerous) or malignant (cancerous).

A condition called pseudomyxoma peritonei can develop when an appendix tumor breaks through the appendix and causes very thick mucin to flow throughout the abdominal space. It surrounds the digestive organs, like the colon, small bowel, and liver and eventually stops them from functioning properly.


The primary types of appendix tumors include:

  • Carcinoid, Adenocarcinoid, and Goblet Cell Appendix Tumors: These slow-growing tumors begin in the appendix and account for about half to two-thirds of cases. They do not usually cause symptoms, unless they spread to other organs.
  • Colonic-Type Adenocarcinoma: Represent about 10 percent of cases and develop at the bottom of the organ, near the colon
  • Non-carcinoid Appendix Tumors: Begin in the wall of the appendix, and produce a thick, sticky substance called mucin
  • Signet-Ring Cell Adenocarcinoma: The rarest and most aggressive form of of this type of cancer


Appendix cancer may not cause any symptoms, or it may cause vague symptoms that are often easily ignored until a serious problem develops. That’s why it’s important to alert your doctor to any new or unusual symptoms.

Symptoms include:

  • Discomfort in the lower right section of your abdominal area
  • Bloating
  • An inflated abdomen, caused by fluid buildup
  • Reflux
  • Lack of appetite
  • Shortness of breath
  • Problems digesting your food
  • Constipation and/or diarrhea

Symptoms of pseudomyxoma peritonei include:

  • Jelly belly, a distended abdomen caused by a mucin buildup
  • Inguinal hernia in men, when a mucinous tumor and/or part of the small intestine bulge through a weak area in the lower abdominal area
  • Ovarian mass or tumor in women

Appendicitis symptoms:

  • Pain and/or swelling in the lower right section of your abdominal area
  • Fever
  • Vomiting and/or nausea
  • Lack of appetite
  • Constipation and/or diarrhea


Appendix tumors frequently go undetected because symptoms are easily explained away. Often, they are found during a routine examination or an abdominal procedure for a different problem, which can include appendicitis, infertility, hernia, ovarian tumors or infertility.

To determine if you are suffering from appendix cancer or pseudomyxoma peritonei, your doctor will need to examine results from one or more tests:

  • Biopsy: Suspicious tissue is removed and examined under a microscope.
  • Computed Tomography (CT) Scan: X-rays and computer technology create a detailed picture of the suspicious area.
  • Magnetic Resonance Imaging (MRI) Scan: Magnetic fields create a detailed picture of the suspicious area.
  • Ultrasound: Sound waves create a picture of the suspicious area.
  • Radionucleotide Scan: A radioactive dye is injected into your body to guide a special camera to the suspicious area.

Once the tumor is diagnosed, your doctor will stage the cancer, determining how extensive the disease is and whether it has spread to other organs. Staging helps your doctor decide on the most effective treatment option.


Both appendix cancer and pseudomyxoma peritonei require prompt treatment. Our doctors have the expertise to provide the best approach, often recommending surgery.

In many cases, treatment involves cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). Treatment may also start with a three-month course of systemic chemotherapy throughout your body, followed by cytoreductive surgery and HIPEC.

Our doctors will perform a thorough evaluation before making their recommendation.


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