HIPEC stands for hyperthermic intraperitoneal chemotherapy, a treatment that delivers heated chemotherapy directly into the abdominal cavity during surgery. It’s used for cancers that have spread to the peritoneum, the thin membrane lining the inside of the abdomen. The procedure combines aggressive tumor removal with a concentrated chemotherapy wash, targeting cancer cells that surgery alone can’t reach.
How HIPEC Works
HIPEC is actually two procedures performed back to back. The first stage is cytoreductive surgery (CRS), where surgeons manually remove all visible tumors from the abdominal cavity. This can include stripping sections of the peritoneal lining, removing portions of affected organs, and cutting away tumor nodules one by one. The goal is to leave behind no visible disease.
Once the surgical debulking is complete, the second stage begins. A heated chemotherapy solution, warmed to 41 to 43 degrees Celsius (about 106 to 109 degrees Fahrenheit), is pumped into the open abdominal cavity through a system of inlet and outlet catheters. The solution circulates continuously for 60 to 90 minutes, bathing every surface where microscopic cancer cells might remain. A heat exchanger connected to a thermostat keeps the temperature stable throughout the process. After the perfusion is complete, the solution is drained, and the abdomen is closed.
The entire operation takes roughly eight to ten hours from start to finish.
Why Heat Makes Chemotherapy More Effective
The “hyperthermic” part of HIPEC isn’t just about warmth. Heat changes the way cancer cells respond to chemotherapy at a biological level. At temperatures between 41 and 43 degrees Celsius, cancer cells become more permeable, meaning their membranes let in more of the chemotherapy drug. Heat also impairs cancer cells’ ability to repair their own DNA, which is one of the main ways tumors survive treatment.
There’s a pressure effect as well. Heating tissue reduces interstitial pressure inside tumor nodules, allowing the drug to penetrate deeper into any remaining cancerous tissue. Meanwhile, the elevated temperature disrupts the internal metabolism of malignant cells, increasing acidity inside them and triggering programmed cell death. Normal healthy cells tolerate these temperatures better than cancer cells do, which is part of what makes the approach selective.
Delivering chemotherapy directly into the abdomen also means the drug reaches cancer cells at much higher concentrations than it would through an IV drip, while exposing the rest of the body to far less of the toxic drug.
Cancers Treated With HIPEC
HIPEC targets cancers that have spread within the abdominal cavity, a pattern called peritoneal metastasis. According to Johns Hopkins Medicine, the most common cancers treated with HIPEC include:
- Appendix cancer
- Colon and rectal cancer
- Ovarian cancer
- Peritoneal mesothelioma
- Stomach (gastric) cancer
- Peritoneal cancer
- Pancreatic cancer
- Liver cancer
- Adrenal cancer
Appendix cancer and peritoneal mesothelioma were among the earliest cancers treated this way and remain some of the strongest use cases. Ovarian cancer has become an increasingly common indication, with clinical trials showing benefits from adding HIPEC to standard surgical treatment.
Who Qualifies for HIPEC
Not everyone with abdominal cancer is a candidate. Two main factors determine eligibility: overall health and how far the cancer has spread. HIPEC is typically reserved for people whose cancer has not spread beyond the peritoneum to distant organs like the lungs or brain. If cancer is found in locations outside the abdomen, the procedure is generally not recommended because the local treatment wouldn’t address distant disease.
You also need to be healthy enough to tolerate a long, demanding surgery. Before being approved, you’ll undergo a thorough evaluation of kidney, liver, and heart function. Your surgical team will review your history of prior chemotherapy, paying close attention to how you responded and any toxicity you experienced. If you’ve been receiving systemic chemotherapy, it typically needs to be stopped at least six weeks before the operation.
Nutritional status matters more than you might expect. The team will assess recent weight loss, body mass index, and blood protein levels. Patients who are malnourished going into the surgery face longer hospital stays and worse outcomes, so nutritional support is sometimes prescribed in the weeks beforehand. If a temporary or permanent ostomy (stoma) might be needed, counseling and skin marking are done before surgery while you’re standing upright.
Recovery After HIPEC
Recovery is significant. Most patients spend their first two or so days after surgery in the ICU, then move to a regular hospital floor for another six to twenty days. Total hospital stays range from roughly one to three weeks depending on the extent of surgery and how the body responds.
Full recovery at home takes an additional stretch, with most people needing at least three months before feeling close to normal. The four to twelve week range is common for returning to regular activities, though some people take longer. During recovery, you’ll be encouraged to walk and move as soon as possible, even while still in the hospital, because staying mobile helps prevent blood clots and other complications from prolonged bed rest.
Risks and Complications
HIPEC combined with cytoreductive surgery is one of the more physically demanding cancer operations, and it carries real risks. The most clinically significant complications involve the gastrointestinal tract. Small bowel perforations and leaks at surgical connection points (anastomoses) are the most common serious problems, with major GI complications reported in 4.5 to 19 percent of patients across large studies.
Pneumonia occurs in roughly 3 to 10 percent of patients, partly because the long surgery and extended recovery period leave the lungs vulnerable. Kidney problems develop in 2 to 4 percent of cases, since the chemotherapy drugs used in HIPEC can stress the kidneys. Blood clots in the veins affect about 4 percent of patients. Urinary tract infections and infections at catheter sites also occur, though less frequently.
The wide range in complication rates reflects differences in how extensive the surgery needs to be. Someone who requires removal of multiple organs and extensive peritoneal stripping faces higher risks than someone with more limited disease. Your surgical team’s experience with the procedure also plays a role: centers that perform HIPEC regularly tend to report lower complication rates.
What Preparation Looks Like
Preparing for HIPEC starts weeks before the operation. Beyond the medical evaluations, you’ll likely be put on a prehabilitation program designed to get your body in the best possible condition for surgery. This includes nutritional optimization, quitting smoking and alcohol if applicable, and building physical fitness where possible.
Certain medications need to be stopped ahead of time. Anti-inflammatory painkillers (NSAIDs) and blood thinners are discontinued to reduce bleeding risk. Your surgical team will calculate your body surface area to determine the exact chemotherapy dose, and they’ll adjust that dose based on your age, organ function, and any other health conditions. The specific chemotherapy drug used varies by cancer type, with the most commonly chosen agents selected based on which cancer is being treated and your individual drug sensitivity.