Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Ovarian Cancer Overview

HIPEC at a glance

• HIPEC stands for hyperthermic intraperitoneal chemotherapy, in other words: heated intra-abdominal chemotherapy
• HIPEC is the administration of heated chemotherapy directly into the abdominal cavity at the time of surgery, in order to directly treat cancer cells
• HIPEC is used in the treatment of ovarian cancer, as well as colorectal cancer and appendiceal cancer

What is HIPEC?

HIPEC stands for hyperthermic intraperitoneal chemotherapy, which is the administration of heated chemotherapy directly into the abdominal cavity. The chemotherapy is administered following a surgical debulking, or surgical tumor resection, while the patient remains asleep. Once the resection portion of the procedure is completed, if all or the majority of the tumor could be removed, a drain system is set up in the abdomen, while the patient is still asleep. This allows the chemotherapy to be administered over the course of 90 minutes, and then washed out of the abdomen. Once the treatment is complete, the abdomen is rinsed of the chemotherapy and then closed in the typical fashion.

In ovarian cancer treatment, HIPEC is administered as part of a neoadjuvant chemotherapy treatment approach, or when chemotherapy is given prior to surgery, soon after diagnosis. Typically, a patient will undergo three to four cycles of neoadjuvant intravenous chemotherapy, and if a response to chemotherapy is seen (evaluated by CT scan and tumor markers), a discussion is had regarding the risks and benefits of surgery and considering the inclusion of HIPEC at the time of surgery. Following surgery with HIPEC, the patient undergoes an additional three cycles of intravenous chemotherapy.

HIPEC provides an advantage over intravenous chemotherapy by its direct contact on the peritoneum, or the lining of the abdominal wall, which is where ovarian cancer often spreads. Heating the chemotherapy increases the impact of the chemotherapy on cancer cells. The heat itself also leads to more destruction of the cancer cells.

In ovarian cancer, cisplatin chemotherapy is used as the primary chemotherapeutic agent in HIPEC.

HIPEC’s Effectiveness

In 2018, a study (van Driel et al., 2018) was published out of the Netherlands that compared women with ovarian cancer who underwent neoadjuvant chemotherapy and subsequent surgery to those who received neoadjuvant chemotherapy and subsequent surgery with HIPEC. This study demonstrated that there was significantly improved survival in women who received HIPEC.

How are HIPEC treatments given?

HIPEC is generally administered as part of a neoadjuvant chemotherapy treatment plan, when a patient receives intravenous chemotherapy prior to surgery soon after her diagnosis. Thus, the patient would undergo three to four cycles of intravenous chemotherapy followed by discussion regarding how her disease has responded to the chemotherapy, as demonstrated on a CT scan and by changes in her tumor marker.

If the decision is made to proceed with surgery, and the patient is thought to be in a state of health where she would be able to tolerate a longer surgery and the potential risks of HIPEC (see below), a conversation may be had regarding the potential benefit of HIPEC. Based on a study from the Netherlands (van Driel et al., 2018), treatment with HIPEC is only appropriate if all or almost all of the cancer is able to be removed surgically, or what is known as an “optimal debulking” is performed. Therefore, the decision of whether or not to administer the chemotherapy intra-abdominally is ultimately made once the surgery is completed, while the patient is still asleep.

If all or almost all of the cancer is able to be surgically removed, the surgical team assembles a drainage system that rests safely in the abdomen. This allows for the chemotherapy to be administered and then removed. The abdomen is then temporarily closed to allow it to be filled with heated chemotherapy. The treatment continues for 90 minutes, while the surgical team keeps the fluid moving. The abdominal cavity is then emptied of all chemotherapy and rinsed with a cleansing fluid. The abdomen is then re-opened and all drains are removed. The abdomen is then closed and the patient is woken up from anesthesia.

Following recovery from surgery with HIPEC, similar to all women who received neoadjuvant chemotherapy for ovarian cancer, the patient will receive three additional cycles of intravenous chemotherapy.

We do not currently have research data to support the use of HIPEC if a patient is undergoing surgery first (prior to intravenous chemotherapy) for ovarian cancer.

Who should consider HIPEC?

• Women with stage III ovarian cancer, who are undergoing their primary treatment, or have been recently diagnosed
• Women who are willing to undergoing a longer, more intensive surgery with the hope of achieving an improved outcome

The chemotherapy used for HIPEC in ovarian cancer, cisplatin, is regularly used as both an intravenous and intra-abdominal chemotherapy option. One of the major risks of cisplatin is damage to the kidneys; other risks include an impact on hearing, and nausea/vomiting.

When administered to the abdominal cavity, the risk to the kidneys remains significant. Thus, as part of the HIPEC procedure, we administer medication to protect the kidneys, and monitor their functioning very closely.

There are also risks associated with the direct administration to the abdominal cavity. There is an increased risk of post-operative ileus, when it takes the bowels a longer time to wake up after surgery. This can lead to nausea and vomiting in the post-operative setting, as well as the need for a nasogastric tube to decompress the stomach.

In general, women who undergo HIPEC for ovarian cancer spend one or two more days in the hospital recovering than our average ovarian cancer surgery patients. There is also an increased likelihood of needing to spend a night or two in the intensive care unit (ICU) immediately following surgery compared to women who do not receive HIPEC.

If you have more questions:

Please ask your provider whether HIPEC makes sense for you as part of your treatment plan.