What is HIPEC? Hyperthermic Intraperitoneal Chemotherapy in Ovarian Cancer

Hyperthermic intraperitoneal chemotherapy represents one of the most significant advances in treating ovarian cancer that has spread throughout the abdominal cavity. 

When standard treatments fall short, this targeted approach delivers heated chemotherapy directly where cancer cells hide, offering hope to patients facing advanced disease.

If you’ve been diagnosed with stage III disease or experienced an ovarian cancer recurrence, understanding HIPEC treatment could be crucial to your care decisions. Here’s what you need to know about this intensive but potentially life-extending procedure.

What Is HIPEC?

HIPEC stands for hyperthermic intraperitoneal chemotherapy. Think of it as a heated chemotherapy bath delivered directly into your abdomen during surgery.

The treatment happens in two stages. 

• First, surgeons perform cytoreductive surgery to remove all visible tumors from your abdominal cavity. This is sometimes called debulking surgery. 
• Then, while you’re still under anesthesia, they pump heated chemotherapy drugs (commonly cisplatin +/- paclitaxel) — typically warmed to about 108 degrees Fahrenheit — throughout your peritoneal cavity for 60 to 90 minutes.

The heat isn’t arbitrary. Cancer cells are more vulnerable to high temperatures than healthy cells, and the warmth helps chemotherapy penetrate deeper into tissues. This combination of direct application and hyperthermia creates a powerful one-two punch against microscopic cancer cells that surgery can’t reach.

Unlike traditional chemotherapy that travels through your bloodstream to reach cancer throughout your body, HIPEC targets a specific area. About 90% of the drug stays within your abdominal cavity, which means higher doses can attack cancer cells directly with reduced systemic exposure. That said, chemotherapy does gradually enter the bloodstream through the peritoneum-plasma barrier, so some systemic toxicity can still occur. 

With cisplatin — the most commonly used drug in HIPEC for ovarian cancer — kidney toxicity is the primary concern, which is why medical teams often administer sodium thiosulfate as a protective measure.

Why HIPEC Matters for Ovarian Cancer

Ovarian cancer has a frustrating tendency to spread across the peritoneum, the membrane lining your abdominal cavity. 

Even after surgery removes visible tumors, microscopic cancer cells often remain scattered throughout this area. Standard intravenous chemotherapy struggles to reach these cells effectively because it can’t penetrate the peritoneal barrier well enough.

That’s where HIPEC treatment becomes crucial. By flooding the abdominal cavity with heated, concentrated chemotherapy immediately after tumor removal, doctors can target those hidden cells before they have a chance to regroup and grow.

One research study found that women with stage III ovarian cancer who received HIPEC after interval debulking surgery lived significantly longer than those who had surgery alone. The median overall survival was 45.7 months in the HIPEC group compared to 33.9 months in the surgery-only group: a difference of nearly 12 months.

Perhaps even more striking: the median recurrence-free survival improved from 10.7 months to 14.2 months with HIPEC, and the treatment didn’t increase serious side effects compared to surgery alone.

Who Benefits Most from HIPEC?

HIPEC isn’t right for everyone with ovarian cancer. The best candidates typically share certain characteristics:

• You have stage III epithelial ovarian cancer that hasn’t spread beyond your peritoneum to distant organs like your lungs or bones. According to NCCN guidelines, select stage IV patients may also be candidates, specifically those who’ve had a favorable response to neoadjuvant chemotherapy both intraperitoneally and extraperitoneally, or whose stage IV disease sites have completely resolved or become resectable (for example, resolution of a malignant pleural effusion).
• You’re generally healthy enough to tolerate major surgery, typically with good heart, lung, kidney, and liver function.
• Your cancer has responded well to initial chemotherapy, showing that it’s sensitive to these drugs.

Complete or optimal cytoreduction is possible, meaning surgeons can remove all visible tumors or leave only tiny residual deposits.

Doctors often use HIPEC ovarian cancer treatment in two main scenarios. The first is interval debulking, where you receive several rounds of chemotherapy first to shrink tumors, then undergo surgery with HIPEC. This is the approach supported by the strongest research evidence. 

The second scenario is recurrent disease, particularly if your cancer came back more than six months after finishing initial treatment and is confined to your abdomen.

Your medical team will also consider something called the Peritoneal Cancer Index, or PCI. This score measures how extensively cancer has spread throughout your abdomen. Generally, a PCI above 20 suggests HIPEC may not provide enough benefit to justify the intensive surgery and recovery.

What About HIPEC for Low-Grade Serous Ovarian Cancer?

If you have low-grade serous ovarian cancer (LGSOC), you might wonder whether HIPEC could help. It’s an important question, particularly because LGSOC tends to be less responsive to standard chemotherapy than high-grade disease.

The reality is that we don’t yet have enough data to say definitively whether HIPEC benefits LGSOC patients. In the landmark trial that established HIPEC’s role in stage III ovarian cancer, only six out of 245 patients had LGSOC — far too few to draw meaningful conclusions about this specific subtype.

Given LGSOC’s known chemoresistance, some doctors theorize that delivering heated chemotherapy directly into the abdomen during surgery might be more effective than systemic treatment. But without clinical trial evidence, this remains speculation.

A global survey of practitioners found that 81% don’t currently recommend HIPEC for LGSOC due to insufficient evidence. Part of the hesitation comes down to the nature of the disease itself: because LGSOC grows more slowly and carries longer survival times than high-grade disease, the added surgical burden — including longer operating times and extended hospital stays — may not justify the benefit. 

The risk-benefit calculation simply looks different when compared to high-grade ovarian cancer, where the urgency and aggressiveness of the disease makes a more intensive approach easier to justify.

If you have LGSOC and are considering all possible treatment options, talk with your gynecologic oncologist about whether HIPEC might be appropriate in your specific situation. They can weigh factors like your disease stage, prior treatment response, and overall health against the limited evidence we currently have.

The HIPEC Procedure: What to Expect

HIPEC surgery is major. Understanding what happens can help you prepare mentally and physically.

The length of the procedure depends almost entirely on how extensive the debulking surgery needs to be. The HIPEC portion itself adds roughly 90 minutes with cisplatin or 60 minutes with paclitaxel, so the total operating time varies widely from patient to patient. You’ll receive general anesthesia throughout, so you won’t be awake during the operation.

After making an incision down the middle of your abdomen, your surgeon removes all visible cancerous tissue. This might include parts of your peritoneum, portions of your bowel, or other affected organs. The goal is complete cytoreduction: removing every tumor the surgeon can see.

Once the cytoreductive surgery is complete, two inflow and two outflow tubes are placed in the pelvic cavity and subdiaphragmatic space. Heated chemotherapy solution — most commonly cisplatin for ovarian cancer — is then pumped through these tubes.

The solution circulates throughout your abdomen, washing over every surface. There are two techniques for this: the open technique, where the abdomen remains open and the surgeon manually manipulates the bowel to ensure full coverage; and the closed technique, where the abdomen is sutured shut and the patient is gently rocked from side to side to distribute the heated chemotherapy evenly.

After 60 to 90 minutes, the chemotherapy is drained and your abdomen is rinsed with sterile solution. Then your surgical incision is closed.

Following the procedure, you’ll be admitted for close monitoring — how much time you spend in intensive care, if any, depends on your individual situation, your surgeon, and the hospital’s protocols. Most patients stay between one and two weeks total.

Understanding the Recovery Process

Recovery from HIPEC treatment takes time and patience. Common side effects during recovery include bloating, fatigue, pain at the incision site, and temporary changes in bowel habits like constipation or diarrhea. Your medical team will monitor you closely for any signs of infection or complications.

Full recovery typically takes four to twelve weeks. During this time, light activity like walking is encouraged to reduce the risk of blood clots and promote healing. As you improve, you’ll gradually increase your activity level under your doctor’s guidance.

HIPEC Chemo: Risks and Considerations

No cancer treatment comes without risks, and HIPEC is no exception. The combination of extensive surgery and high-dose chemotherapy can lead to complications.

Surgical risks include bleeding, infection, blood clots, and potential injury to the bowel or other organs. If your surgeon removes a section of bowel during cytoreduction, there’s a risk the connection site could leak. You might also experience temporary bowel blockage or prolonged bowel inactivity.

The chemotherapy itself can cause kidney toxicity, particularly with cisplatin. Your medical team will monitor your kidney function closely and give you protective medications to reduce this risk. Other potential chemotherapy-related effects include low blood cell counts and nerve damage that causes tingling or numbness.

It’s worth understanding that the overall morbidity risk with HIPEC is significant. This is precisely why patient selection is so carefully considered. Not everyone who could benefit from HIPEC is a suitable candidate, and experienced surgical teams weigh each patient’s individual health profile, disease characteristics, and ability to tolerate a major combined procedure before recommending it. Centers that perform HIPEC regularly tend to have better outcomes, so seeking care at a high-volume institution with dedicated expertise matters.

Research shows HIPEC increased operative time by an average of 127 minutes and extended hospital stays by about 1.5 days compared to surgery alone. Importantly, though, the same analysis confirmed that HIPEC significantly improved overall survival, particularly in primary ovarian cancer cases and when performed after neoadjuvant chemotherapy.

Finding Hope in Advancing Science

HIPEC represents a meaningful step forward in treating advanced ovarian cancer. While it’s not a cure and won’t be right for every patient, the evidence shows it can extend survival and delay recurrence for carefully selected women with stage III disease.

The fact that this intensive treatment provides benefits without dramatically increasing side effects is encouraging. As research continues and techniques are refined, we’re hopeful that HIPEC’s role will become even clearer and potentially expand to help more patients.

Remember that new treatments and clinical trials emerge regularly. If you’re facing advanced ovarian cancer, consider learning about the benefits of ovarian cancer clinical trials and whether participating might be right for you.

Combined with ongoing research, improved surgical techniques, and emerging therapies, we’re moving closer to a future where ovarian cancer is no longer the threat it is today.