Cytoreductive surgery with HIPEC

Cytoreductive surgery with HIPEC is a strategy used for certain tumours that have spread to the peritoneum, the membrane lining the inside of the abdomen and many of its organs. It combines surgery aimed at removing visible tumour disease with the administration, where indicated, of heated chemotherapy into the abdominal cavity.

What is cytoreductive surgery with HIPEC?

Peritoneal tumour disease occurs when cancer spreads across the internal surfaces of the abdomen or, in certain cases, when the tumour itself originates in the peritoneum. Unlike a localised mass, implants can be distributed across different regions and affect several surfaces or organs.

The aim of cytoreductive surgery is to remove all visible tumour disease that can be safely and clinically appropriately excised. To achieve this, peritonectomies – that is, resections of areas of the peritoneum – may be performed, in addition to surgery on parts of the bowel or other affected organs where necessary.

After the surgery is complete, and only when it forms part of the planned strategy, HIPEC (Hyperthermic Intraperitoneal Chemotherapy) may be administered. This involves temporarily circulating a heated chemotherapy solution through the abdomen in an attempt to target microscopic tumour cells that may remain after the visible disease has been removed.

What does it mean to achieve complete cytoreduction?

The term ‘cytoreduction’ can be misleading because it might suggest that the aim is simply to reduce the volume of the tumour. In peritoneal oncology, however, the usual aim is to remove all macroscopic disease — that which can be seen during surgery — provided this can be done without causing a disproportionate risk or loss of function.

At the end of the operation, the amount of visible disease remaining is assessed, amongst other factors. When no macroscopic disease remains, this is usually referred to as a complete cytoreduction. The amount of residual tumour is one of the factors determining the likelihood of subsequent control of the disease.

This issue is particularly important because HIPEC has a limited ability to penetrate deep into tissues. Its action is primarily directed at any potential microscopic residual cells and, therefore, does not compensate for a clearly inadequate cytoreduction.

Tests carried out prior to surgery help to estimate the likelihood of removing the disease, but they do not always reveal small implants or their exact relationship to vital structures. For this reason, the definitive possibility of achieving complete cytoreduction can only be determined after direct exploration of the abdomen.

What are the benefits of HIPEC following surgery?

Once the visible tumour has been removed, a heated chemotherapy solution can be circulated through the abdominal cavity. Direct administration allows high concentrations of the drug to be achieved in contact with the peritoneal surfaces, and the increase in temperature can alter the activity of certain drugs and promote their penetration into the surface tissue.

The drug used, the temperature, the duration of the perfusion and the system employed vary depending on the tumour and the protocol. There is no single HIPEC protocol applicable to all peritoneal diseases.

Part of the drug administered may be absorbed into the systemic circulation. For this reason, HIPEC should not be interpreted as an exclusively local treatment, nor necessarily as a form of chemotherapy with no effect on the rest of the body.

The benefit observed in studies usually corresponds to the overall strategy: cytoreductive surgery, HIPEC where indicated, and other oncological treatments. The specific contribution of the perfusion is not the same for all tumours and must be assessed according to the disease and the available evidence.

For which conditions can it be used?

The indication for cytoreductive surgery with HIPEC varies considerably depending on the tumour of origin. The presence of peritoneal disease does not, in itself, mean that this strategy is appropriate.

In peritoneal pseudomixoma, which is usually associated with certain mucinous neoplasms of the appendix, cytoreductive surgery with HIPEC is the standard of care when the disease is operable and can be adequately resected.

In malignant peritoneal mesothelioma, this strategy may offer prolonged control in carefully selected patients. The complexity of the treatment makes it particularly important that the assessment is carried out by teams with specific experience in peritoneal disease.

In peritoneal metastases from colorectal cancer, complete cytoreductive surgery may benefit certain patients with potentially resectable disease and a favourable clinical profile. The additional benefit of HIPEC depends on the protocol used and is not considered necessary as a matter of routine in all cases.

In advanced ovarian cancer, cytoreductive surgery is a fundamental part of treatment for many patients. The use of HIPEC is, however, restricted to specific clinical scenarios and should not be automatically extended to all situations involving primary disease, relapse or peritoneal involvement.

For other tumours, the strategy may be limited to very specific indications, specialised protocols or clinical trials.

How to assess whether the disease can be removed

Selection begins by determining whether there is a reasonable chance of removing the visible disease and whether the extent of the resections required is proportionate to the expected benefit.

The team analyses the primary tumour and its biological behaviour, the number and distribution of implants, the response to previous treatments, and the possible presence of disease outside the peritoneum. Involvement of the small intestine and other vital structures is of particular importance, as it may limit the possibility of achieving complete cytoreduction or necessitate resections with significant functional consequences.

The patient’s general condition, nutritional status and renal, cardiac, respiratory, hepatic and haematological functions are also assessed. A procedure that is technically feasible may not be clinically appropriate if it necessitates resections that significantly compromise digestive function or the capacity for recovery.

The final decision must balance the possibility of controlling the disease against the extent of the surgery, the foreseeable functional consequences and the patient’s general condition.

Pre-operative assessment and planning

The assessment usually includes a CT scan and, depending on the tumour and any clinical uncertainties, may be supplemented with an MRI, PET scan or other imaging tests. These investigations provide information on the distribution of the implants and enable the assessment of any potential involvement of abdominal organs and structures.

A review of the pathological findings confirms the origin and characteristics of the tumour. In certain situations, a diagnostic laparoscopy may also be performed to directly examine the abdomen and assess whether adequate cytoreduction can be achieved.

The peritoneal carcinomatosis index is a tool that describes the distribution and size of implants in different regions of the abdomen. It helps to organise the information and plan the procedure, but does not in itself determine whether surgery is appropriate: the primary tumour, the location of the disease and, in particular, the involvement of the small intestine are also relevant factors.

Blood tests enable the assessment of kidney and liver function, coagulation, blood cells and other relevant parameters. Nutritional status is also part of the assessment, as extensive surgery may require considerable physical reserves.

The anaesthetic assessment evaluates the patient’s ability to cope with prolonged surgery. Where necessary, Nutrition, Rehabilitation and other specialists may intervene beforehand to improve the patient’s condition prior to surgery.

The management of this condition benefits from a multidisciplinary assessment with specific expertise in peritoneal oncology.

How cytoreductive surgery with HIPEC is performed

The procedure is carried out under general anaesthesia and may last several hours. Its duration depends on the actual spread of the disease, the number and type of resections required, and any reconstructive procedures that need to be carried out afterwards.

The first step involves examining the abdomen and confirming the extent of the implants. Based on this assessment, the necessary peritonectomies and resections are carried out to remove the visible disease to the extent planned.

Where there are implants on the bowel or other organs, it may be necessary to resect the affected segments. If a section of the bowel is removed, one or more anastomoses – that is, surgical connections between the remaining segments – may subsequently be performed.

In certain circumstances, a temporary or permanent ostomy may be required to allow intestinal contents to pass through an opening in the abdominal wall. Whether this is necessary depends on the resections and reconstructions carried out, and not on HIPEC alone.

Most extensive cytoreductive surgeries are performed via open surgery, as this approach allows for extensive exploration and treatment of the abdominal cavity. In very select situations, where the disease is limited and has a favourable distribution, a minimally invasive approach may be considered.

When HIPEC forms part of the treatment plan, it is administered once the cytoreduction has been completed. After the perfusion has finished, the solution is drained, the treated areas are examined, and the reconstructions and surgical closure are completed.

What happens if cytoreduction cannot be completed

During the operation, the disease may be found to be more extensive than anticipated, or essential structures may be affected in a way that could not have been fully determined by the tests carried out prior to surgery.

If continuing would require resections involving disproportionate risk or functional loss, the team may limit or discontinue the initially planned procedure. In these circumstances, HIPEC may not be administered if the degree of cytoreduction required to justify its use has not been achieved.

In certain situations, a more limited procedure may be performed to resolve an obstruction, manage specific symptoms or obtain samples to guide subsequent treatment.

Modifying the plan does not necessarily imply that the surgery has failed. It forms part of intraoperative decision-making and allows the treatment to be adapted to the actual extent of the disease and the consequences of proceeding.

Potential benefits and outcomes

In certain diseases and in carefully selected patients, cytoreductive surgery with HIPEC may offer prolonged periods of disease control and, in some contexts, form part of a curative strategy.

The term ‘curative intent’ means that the treatment aims to eliminate all detectable disease and achieve long-term control. However, it does not guarantee that the tumour will not recur at a later date.

Outcomes depend on the primary tumour, its biological behaviour, the initial extent of the disease, the amount of residual tumour following surgery, and the response to other cancer treatments.

In operable and resectable peritoneal pseudomixoma, this combination constitutes a standard-of-care strategy. In peritoneal mesothelioma, it may offer a significant chance of long-term control in selected patients.

In peritoneal metastases of colorectal origin, the potential benefit is particularly linked to the possibility of achieving complete cytoreduction. In ovarian cancer, the role of HIPEC is limited to specific clinical situations and should not be generalised to all patients.

Risks and potential complications depending on the extent of the surgery

Cytoreductive surgery with HIPEC is a highly complex oncological procedure. The type and likelihood of complications depend on the extent of the resections, the organs treated, the drug used during HIPEC and the clinical characteristics of each individual.

Possible surgical complications include bleeding, infection, thrombosis, respiratory problems and impaired wound healing. When the procedure involves gastrointestinal resections, leaks at the intestinal anastomoses, fistulas, delayed recovery of bowel function, obstruction or the need for additional procedures may occur.

HIPEC may contribute to renal, haematological, hepatic or metabolic abnormalities, depending on the drug used and the amount absorbed into the systemic circulation.

The extent of the risk cannot be summarised by a single figure applicable to everyone. A limited surgical procedure and cytoreductive surgery requiring multiple intestinal or organ resections represent very different situations; therefore, the risk must be assessed according to the procedure actually planned and the individual’s circumstances.

Recovery following cytoreductive surgery with HIPEC

Recovery depends mainly on the extent of the surgery and the resections performed. During the first few days, breathing and circulation, kidney function, fluid balance, blood parameters and the recovery of bowel function are monitored.

Food is reintroduced gradually. Some people may need intravenous or tube feeding for a while, and where an ostomy has been created, the nursing team provides specific training on how to manage it.

After discharge, patients may continue to experience tiredness, loss of strength, reduced appetite, digestive changes and a temporary reduction in independence. Recovery may take weeks or months and, depending on the individual’s needs, may require nutritional support and physical rehabilitation.

Subsequent oncological follow-up depends on the tumour, the results of the histopathological analysis, the degree of cytoreduction achieved and the treatments previously administered. This information helps to determine whether it is necessary to continue with systemic chemotherapy or other strategies.

Alternatives to cytoreductive surgery with HIPEC

The alternatives depend on the primary tumour, the extent of peritoneal disease and the therapeutic objective.

These may include systemic chemotherapy, targeted therapies, immunotherapy, cytoreductive surgery without HIPEC, other intraperitoneal treatments such as PIPAC, or participation in clinical trials.

Where it is not reasonable to attempt to remove all visible disease, procedures aimed at managing specific problems may be considered, such as bowel obstruction, the build-up of abdominal fluid or difficulties in maintaining an adequate diet.

The choice is determined by the nature of the disease, the likelihood of a response, the patient’s general condition, and the balance between benefit, risk and functional impact.

Symptoms requiring medical assessment

After discharge, you should contact the healthcare team if you experience a fever, increasing abdominal pain, persistent vomiting, severe bloating, an inability to eat or drink, or significant changes to your surgical wounds.

You should also seek medical assessment if you experience a marked reduction in urine output, breathing difficulties, swelling or pain in one leg, a prolonged absence of bowel movements, or significant changes in the functioning of an ostomy.

Severe pain, significant bleeding, loss of consciousness, severe breathing difficulties or a rapid deterioration in your general condition require urgent medical attention.

Specialists involved

Cytoreductive surgery with HIPEC requires a multidisciplinary care pathway from initial selection through to recovery and subsequent cancer treatment. The decision-making process begins with establishing the primary tumour, the extent of peritoneal disease and the likelihood of achieving a sufficiently complete cytoreduction.

At the Publio Cordón Memorial Hospital, the Surgical Oncology Department forms the surgical backbone of this care pathway. Its role includes assessing resectability, planning the extent of cytoreduction, and performing the necessary peritonectomies and resections when this strategy is appropriate.

Medical Oncology integrates surgery into the overall cancer treatment plan and assesses its relationship with chemotherapy, immunotherapy, targeted therapies or other treatments. Depending on the tumour’s origin, specific units may be involved, such as the Digestive Tumour Unit for certain gastrointestinal neoplasms, the Gynaecological Tumour Unit, or the Peritoneal Carcinomatosis Unit when the tumour originates in the ovaries or is another gynaecological tumour.

Diagnostic Imaging plays a part in characterising the extent of the disease and provides essential information for assessing resectability and planning the surgical procedure. Pathology confirms the type and characteristics of the tumour and, following surgery, analyses the resected specimens to complete the oncological assessment.

Anaesthetology and Resuscitation is involved in the pre-operative assessment and the anaesthetic management of surgery that may be prolonged and require complex physiological monitoring. Where the clinical situation requires it, Intensive Care is involved in monitoring and providing support during the post-operative period.

Endocrinology and Nutrition may be involved when it is necessary to optimise nutritional status prior to surgery or to support subsequent recovery. Nursing, Hospital Pharmacy, Rehabilitation and other teams are involved depending on the resections performed, the possible presence of a stoma and the functional needs of each individual.

Not all patients require the involvement of all these disciplines at every stage. The team adapts its approach according to the primary tumour, the extent of peritoneal involvement, the planned resections and the needs that arise during recovery and oncological follow-up.

Medical information for general guidance

This information sheet aims to help you understand what cytoreductive surgery with HIPEC involves, the role of each part of the treatment, the conditions for which it may be considered, how the likelihood of removing the disease is assessed, and what recovery entails following surgery of this magnitude. It also explains why the treatment plan may be modified during the operation and what the main available alternatives are.

At the Publio Cordón Memorial Hospital, we believe it is important for medical information to be accurate, understandable and useful in guiding each person through their care journey. Our specialists devote part of their work to explaining conditions, tests and treatment options in an accessible way, helping patients and their families to better understand each stage and participate with greater confidence in decisions about their health. This commitment to knowledge and public outreach is also part of our dedication to research and the advancement of medicine.

The information in this factsheet describes the general principles of cytoreductive surgery with HIPEC. Its use must be tailored to each individual case, taking into account the tumour of origin, the spread of the disease, the likelihood of achieving adequate cytoreduction, the functional consequences of resections, the patient’s general condition and the available alternatives.