Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

What is Peritoneal Cancer?

Peritoneal cancer (peritoneal carcinomatosis) is a variant of progressive, malignant abdominal tumours, which cause multiple metastases on the serous membrane of the abdominal cavity. It develops in every third patient with tumours of the pancreas, stomach and appendix. This complication develops in 10% of patients who suffer from colorectal cancer. Other localisations of the primary tumour which leads to peritoneal cancer include:

• ovaries;
• endometrium;
• fallopian tubes;
• liver;
• gallbladder;
• peritoneum (peritoneal mesothelioma).

There are four stages of the disease. The first stage is characterized by small metastases of up to 5mm in size. All of them are located in one area. At the second stage, the tumours are located diffusely throughout the abdomen. At the third stage, they are from 5 to 20mm in size, whilst at the fourth stage the size of foci may reach over 20mm.

What is HIPEC Surgery?

Surgery remains the main method used to treat patients with abdominal neoplasms. The main tumour is removed. In a case of peritoneal carcinomatosis and the spread of metastases to other organs, a cytoreductive surgery may be performed. This involves the removal of all visible tumour nodes. For this purpose, doctors resect several organs at once.

Nonetheless, the doctors cannot always detect all of the metastatic foci. In addition, many of the foci have microscopic dimensions. Therefore, the probability of cancer recurrence after cytoreductive surgery still remains high. HIPEC (hyperthermic intraperitoneal chemotherapy) serves to reduce this risk. It is used directly during the surgical intervention.

HIPEC surgery allows for the destruction of the remaining foci of tumour cells. The procedure aims to completely eradicate the tumour. If successful, a complete recovery is possible for the patient. However, even if the cancer cannot be cured, HIPEC can significantly increase life expectancy. Approximately two thirds of patients live 5 years or longer after having HIPEC surgery. The procedure also significantly decreases the severity of the symptoms of the disease.

How is the Procedure Performed?

HIPEC is conducted immediately after cytoreduction, that is, after the resection of organs and the destruction of all visible tumour foci.

The doctors place a drainage tube to provide outflow and inflow. Thermal sensors are used to monitor the intra-abdominal temperature. They are located in different parts of the peritoneal cavity. The abdominal skin is sutured with a temporary suture.

The next step is abdominal irrigation with a chemotherapy solution, heated to 42.5 celsius. The total perfusion is about 5 liters. The average flow rate is 700ml per minute. The perfusion is performed using a special apparatus. The average duration of the procedure is an hour and a half. Then, the doctors make a revision of the abdominal cavity. This drains and the surgical wound is sutured.

When treating peritoneal cancer, HIPEC has significant advantages over systemic chemotherapy, where drugs are taken orally or administered intravenously. The advantages are as follows:

• pharmacokinetics – intracavitary administration of drugs can significantly increase the dose;
• hyperthermia – heating of the drug makes it possible to increase the selective antitumor effect, increase the ablastic effect and increase the depth of penetration of the drug into the tumour tissues.