The appendix is a thin pouch that is attached to the large intestine and sits in the lower right part of the stomach. Appendix cancer, which is very rare, occurs when cells in the appendix change and grow significantly. The tissue growth formed from the cells is called a tumor (commonly identified as malignant or benign).
- Appendix cancer is rare.
- Most cases of appendix cancer are found when patients are having appendix-related surgeries like appendicitis or unrelated abdominal surgeries and scans.
- Surgery is the most common treatment option for appendix cancer.
Types of Appendix Cancer
Below are the three types of tumors that can develop in the appendix:
- Carcinoid tumors (commonly referred to as neuroendocrine tumors): A cancerous, rare type of tumor that grows slowly (about half of appendix cancers are carcinoid tumors). Many people with a carcinoid tumor have it for many years before it is detected.
- Mucinous neoplasms: These are generally benign and include appendix mucoceles as well as lesions with precancerous potential such as low-grade mucinous neoplasms (LAMN) of the appendix. If these LAMN lesions perforate or rupture, they can result in a rare condition called pseudomyxoma peritonei (PMP).
- Appendix adenocarcinoma: These tumors begin as cells that line the inside of the appendix and are treated similarly to colorectal cancer. Signet ring cell adenocarcinoma is a very rare subset and tends to be more aggressive.
- Goblet cell carcinomas/adenocarcinoids: These tumors have features of both adenocarcinomas and carcinoids. They are more aggressive than carcinoid tumors.
Symptoms of Appendix Cancer
Symptoms vary from patient to patient and some patients experience no symptoms at all. However, the following symptoms may occur:
- Pain in the stomach or pelvis area
- Ascites (fluid in the abdomen)
Diagnosis of Appendix Cancer
Your physician will consider several factors when diagnosing appendix cancer such as your symptoms, age, medical history and the type of cancer suspected. The following tests may be used to diagnose appendix cancer:
Treatment Options for Appendix Cancer
Treatment options depend on the type and stage of cancer. Your physician will discuss the best treatment options for you. The following treatments may be considered:
- Surgery (the most common treatment for appendix cancer).
The following types of surgeries may be performed:
- Appendectomy: An appendectomy is the removal of the appendix.
- Hemicolectomy: A hemicolectomy is typically performed for a carcinoid tumor that is larger than 2 cm. A portion of the colon that is next to your appendix is removed during this procedure.
- Cytoreductive surgery: Cytoreductive surgery is often recommended for non-carcinoid tumors (tumors that have spread). In this surgery, the tumor and surrounding fluid is removed.
- Peritonectomy: A peritonectomy might be recommended if cancer has spread beyond the colon and involves other areas of the abdomen. Your surgeon may recommend removing the peritoneum (the lining of the abdomen).
- Hyperthermic intraperitoneal chemotherapy (HIPEC)
Risk Factors for Appendix Cancer
Risk factors vary from patient to patient. However, it is important to note that not all risk factors cause cancer. Risk factors for appendix cancer include:
- Smoking: Smokers are more likely to develop appendix cancer than nonsmokers.
- Family history: Patients who have a family history of appendix cancer or multiple endocrine neoplasia type 1 (MEN1) syndrome are at greater risk of getting appendix cancer.
- Medical history: Patients who have a history of certain medical conditions such as atrophic gastritis or pernicious anemia, which affect the stomach’s ability to produce acid, are at greater risk.
- Age: Increasing age raises the chance for developing appendix cancer.
- Gender: Women are more likely to develop carcinoid tumors than men.