Hyperthermic intraperitoneal chemotherapy, also called HIPEC, is a specialized cancer treatment used for cancers that have spread to the lining of the abdominal cavity, known as the peritoneum. HIPEC is typically combined with cytoreductive surgery, also called CRS. CRS is a procedure where surgeons remove all visible cancer from the peritoneum.

After the surgery, the abdominal cavity is bathed with heated chemotherapy to target any remaining microscopic cancer cells. This combined approach, often referred to as HIPEC surgery, can significantly reduce the risk of cancer recurrence, improve survival rates and even offer a potential cure for some people.

During HIPEC, chemotherapy medicine is warmed to around 106 to 109 degrees Fahrenheit (41 to 43 degrees Celsius). This is why HIPEC is often referred to as a "chemo wash" or "hot chemo bath." Heating chemotherapy medicine can help it penetrate into tissues and enhance the medicine's effectiveness.

While traditional systemic chemotherapy circulates drugs throughout the body via the bloodstream, HIPEC is a more targeted approach. It allows for higher medicine concentrations at the cancer site and can lessen the typical side effects people often have with systemic chemotherapy due to less absorption in the bloodstream.

HIPEC is most often used for cancers that have spread to the lining of the abdominal cavity, called the peritoneum. These include:

• Colon or rectal cancer.
• Ovarian cancer.
• Stomach cancer.
• Cancer of the appendix.
• Bladder cancer.

It also may be used for cancers that start in the peritoneum. These include:

• Peritoneal mesothelioma, which is a rare cancer of the peritoneum that is often linked to asbestos exposure.
• Pseudomyxoma peritonei, which is a rare condition where a certain type of cancer cells spread in the peritoneum and cause a jellylike substance to build up.

The combination of HIPEC and CRS can improve survival rates for many cancers. It also can keep cancer from returning or even offer a cure for some people.

However, not everyone is a candidate for HIPEC. HIPEC is typically reserved for people in good health whose cancer has not spread beyond the peritoneum. If cancer has spread to distant organs or someone is not able to tolerate surgery, HIPEC may not be recommended.

To decide if HIPEC is an option for you, healthcare professionals first assess the extent of your cancer. This may be done using imaging scans, such as CT, MRI or PET, or minimally invasive surgery to explore your abdominal cavity.

HIPEC, particularly when combined with cytoreductive surgery, also called CRS, is a complex procedure that carries serious risks, including:

Complications related to surgery

• Reaction to anesthesia.
• Bleeding during or after surgery.
• Blood clots.
• Infection at the surgical site or within the belly.
• If a section of the intestine is removed during CRS, it may leak at the connection site.
• Bowel blockage or temporary bowel inactivity.
• Postsurgery pain that needs pain management.
• Death.

Chemotherapy-related side effects

• Nausea and vomiting.
• Kidney toxicity due to high-dose chemotherapy.
• Bone marrow suppression, leading to low blood cell counts.
• Tingling or numbness caused by nerve damage.

Long-term risks

• Scar tissue, called adhesion, can form at the surgical site. This can cause long-lasting belly pain or problems with the bowels.
• Risk of cancer recurrence, despite treatment.

Preparing for hyperthermic intraperitoneal chemotherapy surgery, also called HIPEC surgery, involves a few steps. During the time leading up to your procedure, you may be asked to:

• Have a medical evaluation. Comprehensive medical tests, including blood work, cardiac assessments and imaging scans, may be done to confirm you're fit for surgery. A healthcare professional may first do a minimally invasive procedure called a diagnostic laparoscopy. During laparoscopy, a care professional uses a small camera and tools inserted through tiny cuts in the skin to look inside the body.
• Stop taking certain medicines. Certain medicines can increase your risk of complications during surgery, so your doctor may ask that you stop taking those medicines before your surgery.

• Optimize your health. Before HIPEC surgery, your healthcare team may recommend an approach called Enhanced Recovery After Surgery, also called ERAS. ERAS is a program of physical, nutritional and mental preparation done before surgery to improve health and resilience.

  ERAS typically includes light exercise such as walking or stretching, a healthy diet, and stress management techniques. It also may include help with quitting alcohol and smoking. The goal is to boost strength, stamina and overall well-being to reduce complications, enhance recovery and improve outcomes after HIPEC surgery.

• Diet and fasting. You may need to follow a special diet or take a bowel-cleansing solution before surgery. Talk with your healthcare team about your instructions.

Plan for your hospital stay

You'll spend at least a few days in the hospital after HIPEC surgery, depending on your situation. Make arrangements for someone to take care of your responsibilities at home and at work.

Think ahead to what you might like to have with you while you're recovering in the hospital. Things you might pack include:

• A robe and slippers.
• Toiletries, such as your toothbrush and toothpaste and, if needed, your shaving supplies.
• Comfortable clothes to wear home.
• Activities to pass the time, such as a book, magazine or games.

During the procedure

Hyperthermic intraperitoneal chemotherapy surgery, also called HIPEC surgery, combined with cytoreductive surgery typically takes 6 to 12 hours, depending on the extent of cancer and surgical complexity. The whole process typically involves the following steps:

• Anesthesia and preparation. After you arrive for your surgery, your healthcare team takes you to a preparation room. Your blood pressure and breathing are monitored. You may receive antibiotic medicine through a vein in your arm.

  You are then taken to an operating room and positioned on a table. You receive general anesthesia medicine to put you in a sleeplike state so that you won't be aware during your operation.

• Surgical cut. The surgeon makes a cut down the middle of the belly to access the abdominal cavity.
• Cancer removal. Cytoreductive surgery, also called CRS, will be done to remove all visible cancer in the abdominal cavity or nearby organs. This is known as debulking. If cancer has spread to the lining of the abdominal cavity, called the peritoneum, the lining itself may be removed. This is called peritonectomy. The goal of CRS is to remove as much visible cancer as possible through debulking or peritonectomy.
• Preparation for HIPEC. After CRS is complete, tubes are placed in the abdominal cavity to deliver and monitor the chemotherapy solution. The cut may be temporarily closed or covered to maintain a sealed environment.
• Heated chemotherapy delivery. A heated chemotherapy solution is pumped into the abdominal cavity using a specialized machine. The solution, containing chemotherapy medicine such as mitomycin C or cisplatin, is circulated for 60 to 90 minutes to target microscopic cancer cells.
• Drainage. After circulation, the chemotherapy solution is drained from the belly. Then the cavity is rinsed with a sterile solution to remove any medicine left behind.
• Closure of the cut. The cut is closed using surgical sutures or staples. Drainage tubes may be left in place to manage fluid buildup postsurgery.

After the procedure

After your procedure, you'll likely stay in the hospital for a few days or longer. Healing after surgery may take time. Full recovery may take around 6 months to 1 year. It's important to rest and take time to recover.

Diet and nutrition

You'll likely have clear liquids on the day of surgery. However, on the next day you may be encouraged to start on a diet of solid food. Eating regular food can help your bowel function return. In addition to solid food, your healthcare team may recommend nutritional supplements to make sure you're getting all the nutrients you need.

Exercise

After surgery, people are typically encouraged to begin light physical activity, such as walking. This can help reduce the risk of complications such as blood clots and promote faster recovery.

As you get better, you can gradually do more physical activities for longer periods of time. This can help restore your strength and endurance. Your healthcare team helps with this process.

The outcome of hyperthermic intraperitoneal chemotherapy surgery, also called HIPEC surgery, depends on several factors. These factors include the type of cancer, how far it has spread, how much of the cancer was removed during surgery, and your overall health.

While HIPEC is a major procedure with risks, studies show that it can offer a meaningful survival benefit for certain people. In general, studies show that people who have HIPEC surgery can live longer than those who have traditional chemotherapy alone, especially when most or all of the cancer can be removed during surgery. However, the benefits are lower if the cancer is widespread or if it can't be fully removed.

Your healthcare team typically monitors you closely after your procedure. It's important to go to all your follow-up appointments after HIPEC surgery because it helps your care team catch any signs of cancer returning early. Regular checkups can improve your chances of staying healthy and living longer.