PIPAC: Aerosol Chemotherapy

What is PIPAC?

PIPAC stands for Pressurized Intraperitoneal Aerosol Chemotherapy.

It is a relatively new technique that allows chemotherapy to be administered directly inside the abdomen, but instead of liquid (as in HIPEC), it is applied as a high-pressure aerosol. This allows the drug to penetrate better into tumor tissues.

How is it different from HIPEC?

How is it performed?

The PIPAC procedure is performed under general anesthesia and follows these steps:

1. Laparoscopy: 2-3 small incisions are made in the abdomen to insert a camera and instruments.
2. Exploration: The surgeon examines the abdominal cavity and evaluates the extent of disease. Biopsies may be taken.
3. Nebulization: A special device is introduced that converts liquid chemotherapy into a fine aerosol.
4. Pressurization: The abdomen is maintained at controlled pressure while the aerosol distributes across all surfaces.
5. Exposure time: The aerosol remains in the abdomen for about 30 minutes.
6. Evacuation: The contents are aspirated and incisions are closed.

Who is it indicated for?

PIPAC can be an option in different situations:

• Extensive peritoneal carcinomatosis: When disease is too extensive for cytoreductive surgery with HIPEC.
• Palliative treatment: To control symptoms like ascites (fluid accumulation) in patients with advanced disease.
• Preparation for surgery: To reduce tumor burden before possible cytoreductive surgery.
• Disease control: To keep disease stable in patients who do not respond well to systemic chemotherapy.

It can also be considered in patients who would not tolerate major surgery due to their health status or age.

Advantages of PIPAC

• Minimally invasive: Only requires small incisions, meaning less pain and faster recovery.
• Repeatable: Can be performed multiple times to maintain disease control.
• Good penetration: Pressurized aerosol penetrates tissues better than conventional liquid.
• Low side effects: Using lower and localized doses, systemic side effects are less.
• Ability to assess response: Each session allows direct observation of how disease is responding.

What to expect after the procedure?

Recovery from PIPAC is generally quick:

• Hospitalization: Usually 1-2 days.
• Pain: Mild to moderate, controllable with common analgesics.
• Feeding: Generally can eat the same day or the next day.
• Normal activity: Most patients resume activities in 1-2 weeks.
• Next session: Usually scheduled every 6-8 weeks.

Possible side effects

PIPAC is usually well tolerated, but the following may occur:

• Mild abdominal pain in the first days
• Temporary nausea
• Abdominal distension
• Fatigue for a few days

Serious complications are uncommon due to the minimally invasive nature of the procedure.

How many sessions are needed?

The number of sessions depends on each individual case and response to treatment. Normally:

• 3-6 sessions are initially planned
• Response is evaluated through exploration and biopsies at each session
• If response is good, cytoreductive surgery with HIPEC may be considered
• If the goal is palliative, treatment continues as long as there is benefit