Overview
The appendix is a pouch-shaped organ, and it is a part of the gastrointestinal tract. Appendix cancer is a type of cancer that occurs when the cells in the appendix lining start growing and dividing abnormally.
It is difficult to detect appendix cancers in their early stages. Appendix cancers could be localised (restricted to appendix only), regional (spread to surrounding lymph tissues) or malignant (spread to distant organs).
Types
Adenocarcinomas are more common primary malignancies than carcinoids. Primary lymphomas can also occur in the appendix. Apart from this, breast cancers, colon cancers and female genital cancers are also seen spreading to the appendix.
Following are the types of appendix tumours:
1. Mucinous Adenocarcinoma: This type of cancer begins in the appendix. It has the unique property of producing mucin, which is a jelly-like substance that causes the cancerous cells to spread to other body parts. Often, these tumours are detected after they have spread to the peritoneum or the abdominal cavity lining.
2. Goblet Cell Carcinoid: This is less common, and its properties are similar to that of mucinous adenocarcinoma. Patients above the age of 50 have a higher risk of developing this condition.
3. Carcinoid Tumour: About 66% of the appendix tumours are carcinoid tumours. They tend to show no symptoms until they reach advanced stages. These tumours tend to form in hormone-producing cells that are present in almost every organ of the body. An appendix carcinoid tumour occurs at the tip of the appendix in most cases. Neuroendocrine tumours are also classified under carcinoid tumours since they originate from the hormone-producing cells and are difficult to detect.
4. Colonic-type Adenocarcinoma: This accounts for 10% of appendix tumour cases. It usually occurs at the base of the appendix. Its properties are similar to that of colorectal cancer. This cancer goes unnoticed often, and it is usually detected during or after the surgery for appendicitis.
5. Signet-ring Cell Adenocarcinoma: It is a rare and aggressive form of adenocarcinoma that is relatively difficult to treat. For the adenocarcinomas that are confined to an appendix, an appendectomy (surgical removal of the vermiform appendix) is recommended.
6. Paraganglioma: This is a rare form of appendix tumour, and it is usually benign. It can be successfully treated with an appendectomy.
Symptoms
Following are the common symptoms that are associated with appendix cancer:
- Pain in the lower right quadrant
- Abdominal bloating
- Abdominal distension
- Reduced appetite
- Constipation
- Diarrhoea
- Digestive disturbances and excessive flatulence
- Appendicitis
- Incidence of hernia
- Shortness of breath
Causes
There is no sufficient information on what causes appendix cancer; also, there are no avoidable risk factors that have been identified. Following are the risk factors that may be associated with appendix cancer:
- Age: The risk of developing appendix cancer increases with age.
- Sex: Neuroendocrine tumours, which are a type of appendix tumours, are more common in women than men.
Diagnosis
Appendix cancers are often detected unexpectedly during or after abdominal surgery.
When appendix cancer is suspected, the doctor may physically examine and apply gentle pressure on the area. The pain released could feel sharp and worse. This could mean that there are some abnormalities associated with the appendix. More tests are conducted to arrive at a conclusive diagnosis.
a. Biopsy: For a biopsy, a small amount of abnormal tissue is excised and examined under a microscope. If cancer growth is found during the surgery, which is most often the case, the doctor may remove a small portion of the organ and surrounding tissues and send it for examination.
b. Imaging tests: Scans such as CT and MRI scans help in obtain accurate information on the size, shape and the exact position of the tumour. Ultrasound is another imaging method for appendix cancer diagnosis. It uses high-frequency sound waves to procedure images that help in pinpointing the tumour position and aiding doctors to perform other diagnostic procedures such as biopsy, aspiration, etc.
c. Radionuclide scanning (Octreoscan): This procedure is largely used if neuroendocrine tumours or carcinoid tumours are suspected. Radioactive octreotide, which is a drug similar to somatostatin, is injected into the veins of the patient. This drug travels throughout the bloodstream and binds to the tumour cells that have receptors for somatostatin. A special camera is then used to obtain images of the regions where radioactive octreotide has been accumulated. This procedure is especially helpful in detecting the spread of carcinoid tumours to organs like the liver.
Treatment
Upon receiving the confirmed diagnosis, the doctors start planning the treatment, which could involve one or more than one treatment modality depending on the type of the tumour, stage of the disease and the patient’s overall condition.
a. Surgery: Surgery is an important line of treatment for appendix cancer. Generally, appendix cancers are of low-grade and slow-growing. Following are the types of surgery performed to treat appendix cancer depending on the stage, size and other parameters associated with the tumour:
- Appendectomy: A surgery performed to remove the appendix.
- Hemicolectomy: This surgery is performed for carcinoid tumours that are larger than 2 centimetres. During hemicolectomy, the surgeon removes the appendix and some portion of the colon.
- Cytoreductive surgery: This procedure is usually recommended for non-carcinoid tumours. During cytoreductive surgery, the tumour and surrounding fluid are removed.
- Peritonectomy: This is surgery performed in cases where cancer has spread to other parts of the stomach. It involves the removal of the peritoneum, which is the lining of the abdomen.
b. Chemotherapy: Chemotherapy is recommended for appendix cancer cases that are in advanced stages where cancer has spread to other parts of the abdomen. Chemotherapy uses potent drugs to kill cancer cells by destroying their ability to grow and divide.
It is often used in combination with other treatment modalities to enhance the efficacy of the overall treatment.
c. Radiation Therapy: Radiation therapy is rarely used in treating appendix cancers. The procedure uses high-energy radiation beams to destroy the tumour cells precisely whilst reducing the damage to the surrounding healthy tissues.
In some cases, radiation therapy is used to relieve symptoms (palliative care) such as pain caused due to cancer spreading to the bones.
Frequently Asked Questions
1. Are appendix cancers treatable?
Yes, appendix cancers are treatable. With a proper approach, even advanced-stage cancers can be treated and managed with positive clinical outcomes. In most cases, appendix cancers are slow-growing and are of low grade, which makes them one of the easily treatable cancers.
However, it is important for the patients to choose the right specialist, who can help with the accurate diagnosis and appropriate treatment.
2. Is appendix cancer hereditary?
There is no sufficient evidence on genetic or familial factors causing appendix cancers.
3. Can a colonoscopy detect appendix cancer?
A colonoscopy, which is an endoscopy procedure used to examine the colon, may help in the detection of appendix cancer. However, this is not the standard procedure for appendix cancer detection and may miss early-stage tumours.
Therefore, it is advised to go for standardised detection and diagnostic procedures. Lastly, it is always better to talk to the doctor, who will be able to give the right guidance on the best diagnostic method.
4. How will they know if the treatment is successful? How will they know if cancer comes back?
Therapy monitoring is an important aspect of cancer treatment. Therapy monitoring is a method of assessing a patient’s response to the cancer treatment administered. If the patient is responding well, then the treatment will continue, and if the response is poor, the doctors may alter the treatment plan in order to achieve a positive clinical outcome.
The cancer treatment will be followed by follow-up care, wherein the patients are asked to undergo regular tests after the treatment ends in order to check if the cancer has relapsed. These tests help in detecting relapse at early stages and supporting appropriate care delivery.