Pressurized Intraperitoneal Aerosol Chemotherapy

PIPAC for Peritoneal Mesothelioma: Pressurized Intraperitoneal Aerosol Chemotherapy, 12 mmHg Delivery, and Repeated Treatment (2026)

PIPAC Quick Facts
Repeated, minimally invasive aerosolized chemotherapy for peritoneal mesothelioma
What It Is	Aerosolized chemotherapy sprayed into the abdomen during laparoscopy
Delivery Pressure	~12 mmHg CO₂ capnoperitoneum
Sessions	Repeated (every ~6 weeks); up to 24 documented in one patient
Distinct From	HIPEC — a single heated bath during open surgery
Key Trial	MESOTIP (NCT03875144) — Phase 2; suspended for safety (febrile neutropenia)
Status	Investigational — not FDA-cleared

Executive Summary

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a minimally invasive way to deliver chemotherapy directly into the abdomen for peritoneal mesothelioma, the form of the disease that grows on the lining of the abdominal cavity. During a short laparoscopy, chemotherapy is turned into an aerosol and sprayed into the abdomen under about 12 mmHg of pressure, which helps the drug spread evenly and penetrate tumor nodules. Unlike hyperthermic intraperitoneal chemotherapy (HIPEC) — a single heated chemotherapy bath given during major open surgery — PIPAC uses low drug doses and is designed to be repeated over multiple sessions. Reported experience includes long-term survival in a patient treated with 24 consecutive PIPAC procedures, and neoadjuvant PIPAC has converted some unresectable cases to surgery. The randomized MESOTIP trial (NCT03875144) was designed to test PIPAC plus systemic chemotherapy against chemotherapy alone, but it was suspended after serious and unexpected adverse reactions — febrile neutropenia — occurred in the PIPAC-plus-chemotherapy arm. PIPAC remains investigational for mesothelioma and is not FDA-cleared.

Why This Matters

Peritoneal mesothelioma is often widespread across the abdominal lining by the time it is found, and not every patient is a candidate for the major cytoreductive surgery that offers the best outcomes. PIPAC is being studied as a gentler, repeatable option — one that can treat the abdominal cavity directly, be given more than once, and in some cases shrink disease enough to make surgery possible. Understanding where PIPAC fits, and how it differs from HIPEC, helps patients and families ask focused questions about treatment at a specialized peritoneal-surface center.

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At a Glance

PIPAC for peritoneal mesothelioma in 2026:

• What it is — chemotherapy converted to an aerosol and sprayed into the abdominal cavity during a keyhole (laparoscopic) operation, under carbon-dioxide pressure of roughly 12 mmHg to improve drug distribution.
• Repeatable by design — PIPAC uses low chemotherapy doses and is intended to be repeated across several sessions, typically weeks apart, rather than given once.
• Distinct from HIPEC — HIPEC is a single dose of heated chemotherapy circulated during open cytoreductive surgery; PIPAC is repeated, aerosolized, pressurized, and minimally invasive.
• Long-term survival reported — a patient with peritoneal mesothelioma treated with 24 consecutive PIPAC procedures achieved long-term survival in a documented case series.
• Conversion to surgery — neoadjuvant PIPAC has been reported to convert initially unresectable peritoneal mesothelioma to candidacy for cytoreductive surgery.
• Underused overall — a German nationwide analysis found that cytoreductive surgery, HIPEC, and PIPAC are all underutilized in peritoneal mesothelioma.
• Key trial status — the randomized MESOTIP trial (NCT03875144), testing PIPAC plus systemic chemotherapy versus chemotherapy alone, was suspended after serious adverse reactions (febrile neutropenia) in the combination arm.
• Investigational — PIPAC is not an FDA-cleared treatment for mesothelioma; it is offered within specialized programs and studies.

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Key Facts

Essential PIPAC Information
Full Name	Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC)
Disease	Malignant peritoneal mesothelioma (abdominal lining)
How It Is Given	Laparoscopic; chemotherapy aerosolized into the abdomen under ~12 mmHg CO₂ pressure
Drug Dose	Low dose (a fraction of systemic doses), repeated across sessions
Contrast: HIPEC	Single heated intraoperative bath during open cytoreductive surgery — high dose, one session
Roles Studied	Repeated palliative control, neoadjuvant conversion to surgery
Pivotal Trial	MESOTIP (NCT03875144) — Phase 2, randomized; suspended for safety (febrile neutropenia in the combination arm)
Regulatory Status	Investigational — not FDA-cleared for mesothelioma

What Is PIPAC and How Does It Work?

PIPAC stands for pressurized intraperitoneal aerosol chemotherapy. Instead of giving chemotherapy through a vein or as a liquid poured into the abdomen, PIPAC turns the drug into a fine aerosol and sprays it into the abdominal cavity during a short laparoscopic (keyhole) procedure. The abdomen is inflated with carbon dioxide to about 12 mmHg — the same capnoperitoneum used for ordinary laparoscopy — and this pressure, combined with the aerosol, helps the chemotherapy distribute more evenly across the peritoneal surface and penetrate deeper into tumor nodules than a simple liquid wash would. Because the doses used are low, PIPAC given on its own is generally well tolerated and, importantly, can be repeated; a course typically involves several sessions spaced roughly six weeks apart, allowing doctors to reassess the disease between treatments. Tolerability can differ when PIPAC is combined with systemic chemotherapy — a combination that produced serious adverse events and halted the MESOTIP trial, as described below.

How Is PIPAC Different From HIPEC?

PIPAC and HIPEC are both ways of treating the peritoneal cavity directly, but they are not the same procedure and are not interchangeable. HIPEC — hyperthermic intraperitoneal chemotherapy — is a single, high-dose bath of heated chemotherapy circulated through the abdomen during open cytoreductive surgery, a major operation that removes visible tumor first. It is delivered once, at the time of surgery. PIPAC, by contrast, is repeated, aerosolized, and minimally invasive: low-dose chemotherapy is sprayed under pressure through small laparoscopic ports, with no large incision and no need to remove all visible disease first. HIPEC is part of an aggressive, potentially curative surgical strategy for selected patients; PIPAC is being studied for patients who may not be surgical candidates, or as a way to control disease and sometimes shrink it enough to make surgery possible later. Framing them as competitors misses the point — they occupy different places in the treatment pathway.

What Does the Evidence Show for PIPAC in Mesothelioma?

The evidence base for PIPAC in peritoneal mesothelioma is still early and consists largely of case series and single-center experience rather than large randomized trials. A current review summarizing the field describes PIPAC's rationale, technique, and the open questions that remain about which patients benefit most. On the encouraging side, a documented case reported long-term survival in a peritoneal mesothelioma patient treated with 24 consecutive PIPAC procedures, illustrating that the treatment can be repeated many times over an extended period. Neoadjuvant PIPAC — using it before surgery — has been reported to convert initially unresectable peritoneal mesothelioma into cases suitable for cytoreductive surgery, potentially extending the reach of curative-intent treatment. At the same time, a German nationwide cohort study found that cytoreductive surgery, HIPEC, and PIPAC are all underutilized in peritoneal mesothelioma, suggesting many patients who might benefit from specialized peritoneal-surface treatment never receive it.

What Is the Status of the MESOTIP Trial?

The most prominent randomized study of PIPAC in mesothelioma is MESOTIP (NCT03875144), a Phase 2 multicenter trial run by the Institut du Cancer de Montpellier that was designed to compare PIPAC combined with systemic chemotherapy against systemic chemotherapy alone as first-line treatment for malignant peritoneal mesothelioma. As registered, the trial's status is listed as Suspended, and the suspension was a safety decision. It followed three cases of serious and unexpected suspected adverse reactions (SUSARs) — specifically febrile neutropenia, a dangerous drop in infection-fighting white blood cells accompanied by fever — in participants assigned to the experimental arm that combined PIPAC with systemic chemotherapy. This safety signal is important context for patients: although PIPAC given on its own uses low chemotherapy doses, combining it with systemic chemotherapy in MESOTIP produced serious toxicity that stopped the trial. PIPAC's randomized evidence in mesothelioma therefore remains limited, and it is best understood as an investigational option offered within specialized programs and studies — not an established standard of care, and not a treatment without risks.

What Does This Mean for Patients?

For a patient with peritoneal mesothelioma, PIPAC is worth knowing about but is not a routine, widely available treatment. It is offered mainly at specialized peritoneal-surface malignancy centers and within clinical studies. Reasonable questions for your care team include whether you are a candidate for cytoreductive surgery with HIPEC, whether PIPAC might be an option if surgery is not feasible or as a way to try to convert to surgery, and whether a clinical trial is available. Because PIPAC is investigational, understanding its goals — disease control and, in some cases, conversion to surgery — helps set realistic expectations. Patients researching active studies can review the mesothelioma clinical trials overview.

Because mesothelioma care is expensive, families are encouraged to document treatment expenses. Compensation for these costs may be available through asbestos trust funds, U.S. Department of Veterans Affairs benefits, and legal claims against the companies responsible for the asbestos exposure that caused the disease. Families weighing their options can consult a mesothelioma law firm such as Danziger & De Llano to understand which compensation channels apply.

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Frequently Asked Questions

What is PIPAC for peritoneal mesothelioma?

PIPAC — pressurized intraperitoneal aerosol chemotherapy — is a minimally invasive treatment that sprays aerosolized chemotherapy into the abdomen during a laparoscopic procedure, under about 12 mmHg of pressure to improve drug distribution. It is used for peritoneal mesothelioma, can be repeated across multiple sessions, and is currently investigational and not FDA-cleared.

Is PIPAC the same as HIPEC?

No. HIPEC is a single dose of heated chemotherapy given during open cytoreductive surgery, whereas PIPAC is repeated, low-dose, aerosolized chemotherapy delivered under pressure through keyhole surgery. HIPEC is part of a major curative-intent operation for selected patients; PIPAC is a gentler, repeatable approach studied for patients who may not be surgical candidates or as a bridge toward surgery.

Does PIPAC cure mesothelioma?

PIPAC is not a proven cure for peritoneal mesothelioma. It is investigational and is studied for controlling disease and, in some cases, shrinking it enough to make cytoreductive surgery possible. Its randomized evidence is limited — the main randomized trial, MESOTIP, was suspended after serious adverse reactions (febrile neutropenia) in the arm combining PIPAC with systemic chemotherapy — so PIPAC should be considered only within a specialized center or clinical study rather than as standard care.

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See Also

• HIPEC (Hyperthermic Intraperitoneal Chemotherapy)
• Peritoneal Mesothelioma
• Mesothelioma Clinical Trials
• Chemotherapy for Mesothelioma
• Mesothelioma Treatment