Peritoneal Cancer

Synonym: Peritoneal carcinomatosis

Introduction

Peritoneal cancer most frequently refers to a metastasis of tumour cells from other tumours in the abdominal cavity into the peritoneum, preferably metastases from pancreatic, liver and ovarian cancer. Initially, the peritoneal carcinoma proceeds without symptoms, but in the course of the disease it often leads to water retention in the abdomen and pain. In very rare cases, the cells of the peritoneum, like all other cells of the body, can degenerate without the causes being known. The therapy of choice, apart from the removal of the original tumour and parts of the peritoneum, is intraperitoneal chemotherapy.

What is the peritoneum and what is it used for?

The peritoneum is a very unknown but very important part of our body for laymen. As a thin skin, it encloses most of the organs of our abdominal cavity, such as the intestine, liver and stomach. The fact that these organs are covered by the peritoneum is extremely important because the peritoneum produces fluid, the abdominal fluid, which serves as a sliding layer for the organs.

This sliding layer enables the digestive organs to move against each other very easily during digestion and prevents intestinal loops from rubbing against each other. You can find more information about this under peritoneum This coating creates a kind of delimited space in the abdomen. This space is also where increased peritoneal fluid collects, which is formed, for example, during inflammation, when bacteria are present in the abdomen or typically when there is liver damage.

This excess of abdominal fluid is called ascites. In extreme cases, several liters of it can even be present in the abdomen. Normal amounts of fluid can be compensated for by the peritoneum, and so the fluid that has collected in the abdomen in the form of lymphatic fluid is reabsorbed every day.

Only when the balance between production and reabsorption is disturbed does ascites develop. It is precisely this characteristic of the peritoneum as a layer covering all organs that makes it very susceptible to the proliferation of tumour cells of the organs embedded in it, as they can easily spread to the other organs via the continuous coating. In very rare cases, the cells of the peritoneum, like all other cells, can also degenerate and proliferate uncontrollably.

Only in very rare cases do the tumours originate directly from the very thin cell layer of the peritoneum, but tumours from other organs are nevertheless very common on the peritoneum and are then called peritoneal carcinomatosis. Almost every tumour growing in one of these organs will sooner or later reach the peritoneum, spread over it and form peritoneal metastases. Peritoneal cancer is therefore usually not the “first” tumour (=primary tumour), but is formed from metastases of various other (primary) tumours. Sometimes the primary tumour is not known at all and the first symptoms are then only triggered by the tumour settling in the form of peritoneal carcinoma. If the metastases are metastases that colonise the peritoneum and lead to peritoneal cancer, these are mostly metastases from daughter tumours of colon cancer, stomach cancer, ovarian cancer, renal cell cancer, liver cell cancer and from gynaecological (e.g. advanced uterine cancer or ovarian or fallopian tube cancer) tumours.