CRS + HIPEC

Introduction

If you or someone close to you has been told that a cancer has spread to the lining of the abdomen, you may have heard the term CRS + HIPEC. It stands for cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy — a long name for a treatment that, in plain terms, removes all the visible cancer from inside the belly and then rinses the abdominal cavity with heated chemotherapy to kill the cells that the eye cannot see.

This article is written for patients and families who are weighing this treatment, or who have been told they are candidates for it, and want to understand what it really involves. CRS + HIPEC is a demanding operation. It is also, for some patients with cancers that were once considered untreatable, one of the few options that offers the possibility of long-term disease control. Understanding how it works, who it is suited for, what recovery looks like, and what the realistic outlook is can help you make decisions and prepare for what lies ahead.

This guide walks through what CRS + HIPEC is, the conditions it is used for, how candidates are selected, what alternatives exist, what happens before, during, and after surgery, and what life can look like in the months and years that follow.

What Is CRS + HIPEC?

CRS + HIPEC is a two-part treatment delivered during a single operation. The two parts are:

• Cytoreductive Surgery (CRS) — the careful surgical removal of all visible cancer deposits from inside the abdominal cavity. This often involves removing parts of the peritoneum (the thin membrane lining the abdomen) and, where the disease has invaded them, parts of organs such as the colon, small intestine, spleen, gallbladder, ovaries, uterus, omentum (the fatty apron that hangs from the stomach), or liver surface.
• Hyperthermic Intraperitoneal Chemotherapy (HIPEC) — immediately after the visible cancer is removed, a heated chemotherapy solution is circulated inside the abdominal cavity for roughly 60 to 90 minutes. The temperature is usually around 41 to 43°C (105 to 109°F).

The reasoning behind combining the two is straightforward. Surgery can take out tumour deposits the surgeon can see and feel, but microscopic cancer cells almost always remain on the peritoneal surfaces. Standard chemotherapy given through the bloodstream often does not reach these surfaces in high enough doses. Delivering heated chemotherapy directly into the abdomen allows the drug to reach those surfaces in much higher concentration than would be safe through a vein. Heat itself appears to make cancer cells more vulnerable and helps the drug penetrate tissue more deeply.

CRS + HIPEC is not chemotherapy in the usual sense. The heated drug stays mostly within the abdominal cavity. While some of it does enter the bloodstream, systemic side effects are typically less severe than with multi-cycle intravenous chemotherapy. The trade-off is that the operation itself is long, complex, and physically demanding.

Why Is CRS + HIPEC Performed?

The treatment is used for cancers that have spread to, or originated from, the peritoneal surface — what doctors call peritoneal carcinomatosis or peritoneal metastasis. Historically, once cancer reached the peritoneum, it was treated almost entirely with palliative chemotherapy. Over the last two decades, evidence from specialised centres has shown that in carefully selected patients with limited peritoneal disease, CRS + HIPEC can extend survival meaningfully, and in some cancer types offer the possibility of long-term remission.

Conditions where CRS + HIPEC is most commonly considered include:

• Pseudomyxoma peritonei — a rare condition, usually starting in the appendix, where mucinous (jelly-like) tumour spreads through the abdomen. CRS + HIPEC is now widely regarded by international expert groups as the standard of care for this disease.
• Peritoneal mesothelioma — a rare cancer of the peritoneal lining itself, distinct from the more familiar lung-related mesothelioma. CRS + HIPEC has substantially changed the outlook compared with chemotherapy alone.
• Colorectal cancer with peritoneal spread — in selected patients with limited peritoneal disease and no widespread distant metastases, CRS + HIPEC may be considered alongside systemic chemotherapy. The role of HIPEC specifically (versus complete cytoreduction alone) continues to be studied.
• Ovarian cancer — HIPEC has been studied at the time of interval cytoreduction (surgery after initial chemotherapy) and for recurrent disease. Major oncology societies have included it as an option in specific clinical situations.
• Gastric (stomach) cancer with limited peritoneal involvement — an evolving indication, generally offered within specialised programmes or clinical trials.
• Appendix cancers other than pseudomyxoma, including some goblet cell tumours and mucinous appendix cancers.
• Rare peritoneal sarcomas in selected cases.

Candidate selection is one of the most important parts of CRS + HIPEC. Doing the operation on the wrong patient can cause significant harm without benefit; doing it on the right patient is where the real survival gains are seen. A specialised peritoneal surface malignancy team typically weighs several factors:

Disease-related factors

• Extent of peritoneal disease. Surgeons use a measure called the Peritoneal Cancer Index (PCI), scored at the start of the operation by mapping tumour deposits across 13 regions of the abdomen. Lower scores generally predict better outcomes. The PCI threshold considered acceptable varies by tumour type.
• Likelihood of complete cytoreduction. The clearest survival benefit is seen when the surgeon can remove all visible disease (or leave only deposits smaller than 2.5 mm). If extensive small-bowel involvement or other features make complete removal unlikely, the operation may not be offered.
• Absence of widespread distant metastases. Cancer that has spread to the lungs, bones, brain, or multiple sites in the liver usually rules CRS + HIPEC out, because the operation cannot address disease outside the abdomen.
• Tumour biology and prior treatment response. Aggressive tumours that grow rapidly despite chemotherapy may not benefit from a major operation.

Patient-related factors

• Adequate fitness for a long operation, ICU stay, and a recovery measured in months.
• Reasonable heart, lung, and kidney function (assessed before surgery).
• Acceptable nutritional status, or a plan to improve it before surgery.
• Realistic understanding of what the operation involves and willingness to participate in a long recovery.

CRS + HIPEC is almost always an adult operation. While there are rare paediatric peritoneal tumours where the principles of cytoreduction apply, the operation as routinely performed in adults is not a standard paediatric treatment, and any paediatric case would be managed in a specialised children’s cancer centre with a tailored plan.

Final candidacy is decided in a multidisciplinary tumour board involving surgical oncology, medical oncology, anaesthesia, radiology, pathology, and critical care.

Alternatives to CRS + HIPEC

CRS + HIPEC is one option among several for peritoneal disease. Depending on the cancer type, extent, and the patient’s overall health, alternatives may include:

Systemic chemotherapy alone

For most cancers with peritoneal spread, intravenous chemotherapy is part of the treatment. For some patients — particularly those with extensive disease, poor fitness, or aggressive tumour biology — systemic chemotherapy without CRS + HIPEC remains the standard. Newer drug combinations, including targeted therapies and immunotherapy in specific cancer types, continue to improve what chemotherapy alone can offer.

Cytoreductive surgery without HIPEC

In some situations, the surgical removal of visible disease (sometimes called debulking) is performed without adding heated chemotherapy. This is particularly relevant in some ovarian cancer settings and is an active area of research in colorectal peritoneal disease. The question of when HIPEC adds meaningful benefit on top of complete surgical removal is one that ongoing trials are still answering.

Pressurised Intraperitoneal Aerosol Chemotherapy (PIPAC)

PIPAC is a newer, less invasive technique where chemotherapy is sprayed as an aerosol into the abdomen during a short keyhole procedure. It is typically used in patients who are not candidates for full CRS + HIPEC, often as a palliative treatment to control symptoms and disease progression. It does not aim to remove the cancer.

Targeted therapy and immunotherapy

For some cancers — notably certain colorectal, ovarian, and gastric cancers — molecular testing of the tumour can identify markers that make targeted drugs or immunotherapy options. These treatments may be used in place of, before, or after CRS + HIPEC depending on the situation.

Best supportive care

For patients with advanced disease where aggressive treatment is unlikely to extend or improve life, the focus may shift to symptom control, nutrition, drainage of fluid build-up (ascites), and quality of life. This is a legitimate and important option, and one that should be discussed openly when the burden of an operation outweighs likely benefit.

The choice between these options is one for you and your oncology team to work through together, based on the specific cancer type, how far it has spread, your overall health, and your own priorities.

The Surgical and Chemotherapy Approach

CRS + HIPEC is overwhelmingly performed as open surgery through a long midline incision running from below the breastbone to the pubic bone. This is because the surgeon needs direct access to every surface of the abdomen, including the diaphragm above and the pelvis below, to identify and remove every visible deposit.

Open CRS + HIPEC

This is the standard approach worldwide and the one used for the great majority of patients. The wide exposure allows complete inspection, accurate PCI scoring at the start, and the multiple resections (organ or peritoneal removals) that complete cytoreduction often requires.

Laparoscopic and robotic CRS + HIPEC

In carefully selected patients with very limited peritoneal disease — for example, low-volume pseudomyxoma peritonei or a small number of peritoneal nodules — some specialised centres have explored minimally invasive cytoreduction with HIPEC. These approaches are not yet standard, are limited to centres with specific expertise, and are not appropriate when disease is widespread. Open surgery remains the default.

Two main HIPEC delivery techniques

Once cytoreduction is complete, the heated chemotherapy can be circulated using one of two techniques:

• Open (Coliseum) technique — the abdomen is held open with a retractor and the surgeon gently moves the fluid by hand to ensure even contact with all surfaces.
• Closed technique — the abdomen is temporarily closed and the heated chemotherapy is circulated through inflow and outflow catheters, with the abdominal wall manipulated externally to distribute the fluid.

Both techniques are used in different centres; each has practical advantages and trade-offs that the surgical team will choose between.

Preparing for CRS + HIPEC

Because the operation is long and the recovery demanding, preparation matters. Most centres run patients through a structured pre-operative workup over several weeks.

Imaging and disease assessment

• Contrast-enhanced CT scan of the chest, abdomen, and pelvis to map the disease and look for any spread outside the abdomen.
• PET-CT scan in selected cases, particularly to look for distant metastases that would change the plan.
• MRI in some situations, particularly when assessing the liver or pelvic disease.
• Diagnostic laparoscopy — a short keyhole procedure to look directly inside the abdomen and assess whether complete cytoreduction is likely. This may be done in a separate sitting before the main operation.

Blood and tumour marker tests

Standard blood tests, kidney and liver function, clotting tests, and tumour markers relevant to your cancer type (such as CEA, CA 19-9, or CA 125) help establish a baseline.

Fitness assessment

• Heart assessment, often including an ECG and echocardiogram.
• Lung function tests if there is any concern about breathing capacity.
• An anaesthetic review focused on tolerance of a long operation.
• Where available, formal cardiopulmonary exercise testing (CPET) to predict surgical fitness.

Nutrition and prehabilitation

Patients with cancer often arrive at surgery underweight or with reduced muscle mass. Many programmes now use a structured prehabilitation approach: nutritional support, protein supplementation, light exercise to build stamina, smoking cessation if relevant, and management of any other medical conditions. Improving fitness before surgery is associated with smoother recovery.

Other preparation

• Bowel preparation may be required depending on the planned resections.
• A review of all medications, including blood thinners and supplements, with clear instructions on what to stop and when.
• Vaccination, if a spleen removal is anticipated (against certain bacteria that the spleen normally protects against).
• Discussion of stoma possibility — in some operations, part of the bowel may need to be brought to the skin surface temporarily or permanently. Marking and education with a stoma nurse before surgery is helpful.
• A clear conversation about what the operation may and may not achieve, including the possibility that, once the abdomen is opened, the disease may be more extensive than imaging suggested and the operation may be abandoned (called an “open and close”).

What Happens During CRS + HIPEC

Anaesthesia and monitoring

You will be under general anaesthesia throughout. An epidural catheter is often placed for pain control. Multiple intravenous lines, a urinary catheter, an arterial line for blood pressure monitoring, and sometimes a central venous catheter are placed before the operation begins. Temperature, fluid balance, and blood chemistry are monitored very closely throughout, particularly during the heated chemotherapy phase.

Step 1: Exploration and PCI scoring

After opening the abdomen, the surgeon systematically examines all 13 regions of the abdomen and pelvis, assigning a score for the size of tumour deposits in each. This produces the PCI, which guides the decision on whether to proceed.

Step 2: Cytoreductive surgery (CRS)

The surgeon then removes all visible disease. This may include:

• Stripping of the peritoneum from the diaphragm, pelvis, and abdominal wall.
• Removal of the omentum (omentectomy).
• Removal of segments of small or large intestine, sometimes with re-joining of bowel ends or, if needed, formation of a stoma.
• Removal of the gallbladder, spleen, part of the stomach, or part of the liver surface.
• In women, removal of the ovaries, fallopian tubes, and uterus, depending on the disease.
• Targeted removal of any other deposits found.

The goal is what surgeons call complete cytoreduction — no visible disease left behind, or only deposits smaller than 2.5 mm. The degree of completeness is recorded as a CC score (CC-0 through CC-3); CC-0 and CC-1 are associated with the best outcomes.

Step 3: HIPEC

Once cytoreduction is complete, the HIPEC phase begins. Catheters are placed into the abdomen, and a perfusion machine circulates a chemotherapy solution heated to 41–43°C through the abdominal cavity for about 60 to 90 minutes. The specific drug or combination depends on the cancer type — mitomycin C, oxaliplatin, cisplatin, and doxorubicin are among those commonly used. Temperature is closely controlled, and the anaesthesia team manages the patient’s core temperature, fluids, and blood chemistry throughout.

Step 4: Reconstruction and closure

After the chemotherapy is drained out, the abdomen is rinsed. Any bowel reconstructions (joining of cut ends or stoma formation) that were postponed are completed at this point. Drains are placed, and the abdomen is closed.

Recovery and Healing

The first few days: intensive care

After surgery, you will typically be transferred to an intensive care unit (ICU) for 2 to 5 days. The team monitors heart and lung function, fluid balance, kidney function, blood chemistry, and pain. You may be on a ventilator briefly. Pain is managed through a combination of epidural medication and other pain relief.

Stepping down to the ward

Once stable, you move to a surgical or oncology ward. The total hospital stay is usually 2 to 3 weeks but can be longer if there are complications. During this time, the focus is on:

• Gradually restarting the gut and resuming oral intake. Bowel function often takes longer than usual to return after CRS + HIPEC.
• Nutrition — many patients need supplemental nutrition, sometimes intravenously, until they can eat enough by mouth.
• Pain control, transitioning from epidural to oral medication.
• Walking, sitting out of bed, and chest physiotherapy to reduce the risk of pneumonia and blood clots.
• Wound and drain care.
• If a stoma was made, training in how to care for it before discharge.

The first weeks at home

You can expect significant fatigue for several weeks. Most patients describe the first month as the hardest part of recovery. Appetite is often reduced, and weight loss is common before gradually being regained. Bowel habits may take time to settle. Sleep can be disrupted. Emotional reactions — relief, low mood, anxiety, or simply feeling overwhelmed — are all common and worth acknowledging.

Recovery milestones

• 4–6 weeks: wound healing is well underway; light activity at home; gradual increase in walking distance.
• 2–3 months: most patients are managing daily activities; energy is improving but not yet normal.
• 3–6 months: most patients describe being close to their previous level of function, though some fatigue may persist.
• 6–12 months: for many, a sense of full recovery, though individuals vary widely.

Recovery is not linear. Setbacks — a chest infection, a wound issue, a few days of poor appetite — are common and usually resolve. Your surgical team will give you specific instructions on lifting, driving, returning to work, and signs that should prompt you to call.

Risks and Complications

CRS + HIPEC is one of the most extensive operations in cancer surgery. Complications are not rare, and an honest understanding of the risks is part of informed consent. The exact risk profile depends on the extent of the cytoreduction, the chemotherapy used, your overall health, and the experience of the centre performing the operation.

Surgical complications

• Bleeding during or after surgery.
• Anastomotic leak — leakage from a join in the bowel, which may require further surgery or drainage.
• Intra-abdominal infection or abscess.
• Wound infection or delayed wound healing.
• Blood clots in the legs (DVT) or lungs (pulmonary embolism).
• Bowel obstruction, either early or later.
• Prolonged ileus — a sluggish gut that delays return to eating.

Chemotherapy-related effects

• Kidney stress from the heated chemotherapy — carefully managed with fluids and monitoring.
• Temporary drops in blood counts (white cells, platelets).
• Nausea.
• Rare but more serious reactions to specific drugs.

Medical complications

• Chest infection or pneumonia.
• Heart rhythm disturbances, particularly atrial fibrillation.
• Acute kidney injury.
• Need for blood transfusion.

Longer-term issues

• Adhesions inside the abdomen, which can sometimes cause bowel obstruction months or years later.
• Changes in bowel habit.
• If a stoma was created, ongoing stoma care.
• Fatigue lasting several months.
• Hernias at the incision site.
• Fertility loss, if the ovaries and uterus were removed; and surgical menopause in women who had not yet gone through it.

Major published series have consistently shown that complication and mortality rates fall substantially when CRS + HIPEC is performed in high-volume specialised centres with experienced multidisciplinary teams. This is one of the strongest arguments for being treated at a centre with a dedicated peritoneal surface malignancy programme.

Life After CRS + HIPEC

For many patients, life after CRS + HIPEC settles into a new normal over six to twelve months. The shape of that new normal depends on the cancer type, the extent of the operation, and your own pace of recovery.

Follow-up and surveillance

• Clinic visits every 3 to 6 months for the first 2–3 years, then less often.
• CT scans of the chest, abdomen, and pelvis at regular intervals.
• Blood tumour markers relevant to your cancer type.
• In some cases, MRI or PET-CT.

The exact schedule is tailored to your cancer type, your PCI, the completeness of cytoreduction, and your overall picture.

Adjuvant or further treatment

Some patients receive additional systemic chemotherapy after recovery from surgery; others complete chemotherapy before surgery and need no further drug treatment afterwards. The plan is decided jointly by the surgical and medical oncology teams based on the cancer type and what surgery achieved.

Diet, weight, and bowel habit

Many patients need time to relearn how they eat. Smaller, more frequent meals, attention to protein, and adequate hydration help. A dietitian familiar with post-operative cancer patients is a useful resource. Some find that certain foods are easier to tolerate than others, and that this changes over months.

Physical activity

Gradual return to walking and, later, more sustained exercise is encouraged once the surgical team confirms it is safe. Rebuilding muscle mass, lost during the operation and recovery, takes time and steady effort.

Emotional and psychological aspects

The combination of a serious cancer diagnosis, a long operation, and a slow recovery is a heavy load. Anxiety about scan results (sometimes called “scanxiety”), low mood, sleep disturbance, and changes in body image are all common. Counselling, peer support groups, and, where appropriate, psychiatric or psychological care are part of comprehensive cancer care and should not feel like extras.

Return to work and relationships

Most patients who were previously working can return to some form of work within a few months, often part-time at first. Conversations with family about what you can and cannot do during recovery, and about the realities of cancer follow-up, are often more useful than trying to act as though nothing has changed.

Outlook

Outcomes after CRS + HIPEC vary widely. They depend on the cancer type, how completely the disease could be removed, the PCI score, the tumour’s biology, and the response to any additional treatment. In broad terms:

• Pseudomyxoma peritonei generally has the most favourable long-term outlook of the conditions treated with CRS + HIPEC, with many patients living for many years and some considered effectively cured.
• Peritoneal mesothelioma survival has improved substantially compared with chemotherapy alone in specialised centres.
• Colorectal peritoneal disease outcomes are intermediate and depend heavily on PCI and completeness of cytoreduction.
• Ovarian and gastric peritoneal disease outcomes are influenced by tumour biology and response to systemic treatment.

Studies suggest that across these conditions, achieving complete cytoreduction is the single strongest predictor of long-term survival. Personalised estimates of outlook are best discussed with your surgical and medical oncology team, who can take into account the specifics of your disease and how the operation went.

Frequently Asked Questions

Is CRS + HIPEC a cure?

For some patients with certain conditions — particularly pseudomyxoma peritonei and selected peritoneal mesotheliomas — CRS + HIPEC can achieve long-term disease control that, in practical terms, behaves like a cure. For other cancers, it is more accurately described as a treatment that can meaningfully extend survival and quality of life in selected patients. Your team can give you a realistic picture based on your specific disease.

How long does the operation take?

Typically 6 to 12 hours, occasionally longer. The duration depends on how much disease has to be removed.

Why heated chemotherapy?

Heat enhances the effect of certain chemotherapy drugs on cancer cells and helps the drug penetrate tissue more deeply. Delivering the drug directly into the abdomen allows much higher local concentrations than would be safe if the drug were given through a vein.

Will I need a stoma?

It depends on what parts of the bowel are removed and how they can be reconnected. Some patients leave with a temporary stoma that is reversed later; some have no stoma; a smaller number need a permanent stoma. Your surgical team should discuss the likelihood with you before surgery and, where there is a real possibility, arrange to meet a stoma nurse.

How long will I be in hospital?

Most patients spend 2 to 5 days in intensive care and a total of 2 to 3 weeks in hospital, sometimes longer if there are complications.

When can I return to normal activities?

Light activities at home usually resume in the first few weeks. Most patients are managing daily life by 2 to 3 months and feel close to their previous level of energy by 3 to 6 months. Heavy lifting and strenuous exercise are usually avoided for at least 6 to 8 weeks, or as the surgical team advises.

Will I need more chemotherapy after CRS + HIPEC?

This depends on your cancer type and the overall treatment plan. Some patients receive chemotherapy before surgery only; others receive it after; some receive both; some need none beyond HIPEC. The medical oncology team decides this with you.

Can the operation be done with keyhole surgery?

For the great majority of patients, open surgery is standard, because the surgeon needs full access to every surface of the abdomen. Laparoscopic and robotic approaches are being explored in highly selected patients with very limited disease in specialised centres, but they are not the norm.

What if the surgeon opens the abdomen and finds more disease than expected?

If, on opening, the disease is too extensive for complete cytoreduction, the operation may be abandoned without HIPEC. This is sometimes called an “open and close” and is one reason careful pre-operative assessment and, in some centres, a diagnostic laparoscopy beforehand are important.

How is fertility affected?

If the ovaries and uterus need to be removed as part of cytoreduction, fertility ends and women not yet menopausal will go through surgical menopause. Where fertility preservation is relevant, it should be discussed before surgery with a reproductive specialist.

Why is it so important to choose an experienced centre?

Outcomes in CRS + HIPEC are strongly linked to the experience of the surgical and intensive care teams. High-volume specialised centres consistently report lower complication and mortality rates and better long-term results. International expert groups have emphasised the importance of concentrating this work in dedicated peritoneal surface malignancy programmes.

Conclusion

CRS + HIPEC is one of the most extensive and demanding treatments in cancer surgery, and at the same time one of the few that has fundamentally changed the outlook for cancers once considered untreatable. For patients with peritoneal disease from pseudomyxoma peritonei, peritoneal mesothelioma, and selected colorectal, ovarian, gastric, and appendix cancers, it offers the possibility of long-term disease control that systemic treatments alone usually cannot deliver.

The treatment is not for everyone. It works best when the disease is limited enough to be fully removed, when the patient is fit enough to undergo a long operation and a long recovery, and when the work is done by an experienced multidisciplinary team that can manage every stage from selection through to follow-up. Where these conditions are met, the outcomes can be substantial; where they are not, the burden of the operation can outweigh the benefit. That is why patient selection, an honest pre-operative conversation, and treatment in a specialised centre matter so much.

If you are considering CRS + HIPEC, the most useful next steps are a detailed discussion with a surgical oncology team that performs this operation regularly, a clear understanding of what the operation can and cannot do for your specific disease, and a realistic plan for the months of recovery that follow. With the right preparation and the right team, CRS + HIPEC remains one of the most powerful tools modern oncology has for cancers of the peritoneal surface.