Origin of peritoneal cancer

PC from Gastric Cancer

Cancer of the stomach (“gastric cancer”) has a high tendency to metastasize to the peritoneal cavity. It is estimated that at least 30% of patients with gastric cancer develop peritoneal cancer at some stage during their disease.

Peritoneal cancer can develop in every gastric cancer patient, but previous research has identified various risk factors. Peritoneal cancer develops more often in younger patients (below the age of 60), in women and patients with an advanced tumor (e.g., high “T-stage”). A subtype of gastric cancer, known as “signet cell cancer” also has higher chances of causing peritoneal cancer.

The prognosis for these patients is usually bad because a recent large study has shown the median survival is only four months after diagnosis.

For patients in good clinical condition, palliative systemic chemotherapy may be advised, and this treatment approach may prolong survival and improve the patient’s clinical condition.

Some hospitals around the world now offer HIPEC for peritoneal cancer of a gastric origin and have reported relatively good results in patients with limited disease. However, the additional value of HIPEC for gastric cancer patients has never been demonstrated in a good clinical study comparing HIPEC to other treatments. Additionally, side effects of this treatment in combination with gastric cancer surgery are frequent and may be severe. Therefore, it is advised that HIPEC for peritoneal cancer of a gastric origin should preferably be performed through a clinical study program.

In some hospitals, the value of adjuvant HIPEC for gastric cancer patients at high risk for developing peritoneal cancer after their operation is currently under investigation. The reason for administering HIPEC is the assumption that microscopic tumor cells are already present in the abdominal cavity following the operation and these cells will cause peritoneal cancer if left untreated. The heated chemotherapy aims to destroy these tumor cells and to prevent the development of peritoneal cancer. Results from these studies still need to be assessed. Until then, adjuvant HIPEC should not be considered as the standard of care in gastric cancer patients.