Tumours of the appendix

What are the different tumours that can happen in the appendix?

• Neuroendocrine tumours which are relatively slow growing but have potential to spread
• Mucinous neoplasms which are usually low or intermediate grade tumours but have potential to cause rupture of appendix and deposition of mucinous material in the abdomen known as pseudomyxoma peritonei.
• Adenocarcinoma which behaves like colon cancers The prognosis of all these can be very different

How are tumours of the appendix present?

• Most of the appendix tumours are diagnosed after surgery for appendicitis, It can be difficult to diagnose these conditions prior to the procedure.
• Few of them present with symptoms of peritoneal metastases like abdominal distension and symptoms of bowel obstruction.
• In pseudomyxoma peritonei there is deposition of mucoid material all over the abdomen and patients usually present with painless distension of the abdomen

What is the usual evaluation which is done?

The usual evaluation done is a CT scan . If the tumour has grown to a particular size then it can be detected on CT scan.

Colonoscopy is required but it may miss tumours of the appendix PET scan is of limited value as most of the tumours tend to be low grade

How are appendix tumours treated ?

Surgery forms the main treatment in low grade tumours which have not spread Appendicectomy may be sufficient if the tumour is limited to the tip of the appendix In larger tumours and those which have reached the base of the appendix hemicolectomy may be required.

Chemotherapy is used in appendix cancers which have spread to other organs

How is pseudomyxoma peritonei treated ?

Pseudomyxoma is a condition in which there is an accumulation of mucus in the abdomen. Fortunately, it is a rare disease, It happens due to a rupture of a mucous-secreting organ like an appendix or less commonly due to a rupture of a mucinous tumour of the ovary. Cytoreductive surgery and HIPEC is used to treat Pseudomyxoma.

What is cytoreductive surgery?

It is a type of surgery performed for certain cancers like that of the ovary. In this surgery attempt is made to remove all the disease in the abdomen and leave behind no visible disease, This may involve removing multiple organs in the abdomen.

The surgery is not only performed in ovarian cancer but it is performed on cancer like peritoneal mesotheliomas, pseudomyxoma peritonei and primary peritoneal cancers.

What are the challenges in performing cytoreductive surgery?

While most surgeries are performed in well-defined anatomical landmarks, cytoreductive surgery is not so. The disease is present anywhere in the abdomen and proper anatomical knowledge of the entire abdomen is required to competently perform these surgeries. Cytoreductive surgery very often requires:

• Stripping of the inner layer of the abdomen is Peritonectomies
• Omentectomy – removal of the omentum
• Stripping of the liver capsule
• Multiple bowel resections may have to be performed
• The removal of the spleen if the disease is present on it

Such surgeries take a long time and need considerable experience to perform safely.

What is HIPEC?

HIPEC stands for Hyperthermic Intra peritoneal chemotherapy. HIPEC is a method of delivery of chemotherapy directly into the abdomen.

It is used in conditions like carcinoma ovary, primary peritoneal carcinoma, pseudomyxoma peritonei and mesotheliomas

HIPEC is usually combined with cytoreductive surgery