Peritoneal spread from tumor of the Appendix

Tumors of the appendix that produce mucin are the most common cause of a rare peritoneal cancer called pseudomyxoma peritonei (PMP)


Know about

Appendix Cancer

The Appendix is a small pouch of tissue which lies at the junction of the small and large intestines. Tumor of the appendix are very rare. Most patients are diagnosed after undergoing surgery for acute appendicitis or when an abdominal mass is seen during a CT scan for any unrelated condition.

This is one group of cancers for which there is no known cause. It’s not a hereditary cancer, nor is it related to any particular lifestyle.

Types of Appendix Cancer

Tumors of the appendix can be divided into two major groups:

Carcinoid Tumors and Non-carcinoid tumors.

Carcinoid Tumors are the slow growing cancerous tumours which grow in several parts throughout the body. The symptoms of these tumors do not appear until late in the disease.

Non carcinoid tumors have a propensity to spread to the peritoneal cavity. These tumors of the appendix originate from the epithelial cells, lining the inside of the appendix. Most of the cells creating these tumors produce a gelatinous material known as mucin. The mucin keeps collecting as the appendix is narrow. Eventually the wall of the appendix ruptures and the mucin along with the cells producing the mucin spreads in the abdominal cavity and produces peritoneal cancer.

If left untreated, both tumor cells and mucin will continue to accumulate and over a period of time lead to life-threatening bowel obstruction and weight loss, loss of appetite, fatigue. Prognosis and treatment for these tumors depend on a number of patient and tumor-related factors.

A typical low grade mucinous tumor of the appendix. It arises near the tip, ruptures and causes spread over the entire peritoneal cavity leading to pseudomyxoma peritonei. Appendiceal mucinous tumors can be fast growing or of the high grade variety also.

A typical high grade tumor that arises from the base and grows along the large intestine. This tumor will cause peritoneal spread that is around the tumor and later spreads to other areas. It also has a propensity to spread to the glands and other organs of the body like the liver and lungs

Symptoms & Diagnosis

This tumor may not produce any signs or symptoms till it has spread to the peritoneal cavity. Sometimes it produces a dull ache, bloating and discomfort.

When the tumor is confined to the appendix, it may mimic acute appendicitis. Sometimes it is detected during surgery or as a mass on CT scan. When widespread, it presents as a pseudomyxoma peritonei. Pseudomyxoma peritonei produces classic signs on a CT scan that helps in the diagnosis. Sometimes it may mimic ovarian cancer and the diagnosis is only made during surgery for the same.

Treatment of Appendix Cancer

When the tumor is confined to the appendix, patients will have to undergo surgery to remove the appendix and/or right colon. In the majority of the patients with tumors of the low grade variety, removal of the colon is not required and removal of the appendix alone is sufficient.

For patients in whom the tumor has spread to the peritoneal cavity, the combined approach of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) is the most effective and beneficial treatment.

Low grade tumors and high grade tumors both have an excellent outcome with this kind of treatment, with patients surviving for 5-10 years and even more. Patients with low-grade tumors live longer compared to those with high-grade tumors on average.