Peritoneal dissemination is a common route of cancer metastasis. The benefit of administering
chemotherapy directly into the peritoneal cavity is supported by preclinical and
pharmacokinetic data. In comparison to intravenous (IV) treatment intraperitoneal (IP)
administration results in a several-fold increase in drug concentration within the abdominal
cavity. There is now growing evidence from clinical studies showing a survival advantage for IP
chemotherapy in various tumor typies including ovarian gastric and colorectal cancer.However
while the use of IP chemotherapy is slowly gaining acceptance it is not universal largely due
to the greater toxicity associated with this approach. Moreover efficacy of IP chemotherapy is
limited by poor distribution within the abdominal cavity and by poor tissue penetration. A new
way of IP chemotherapy is the application of cytotoxics in form of a pressurized aerosol into
the abdominal of thoracic cavity. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is
applied through laparoscopic access using two balloon trocars in an operating room equipped
with laminar air-flow. In a first step a normothermic capnoperitoneum is established with a
pressure of 12 mmHg. A cytotoxic solution (about 10% of a normal systemic dose) is nebulized
with a micropump into the abdominal cavity and maintained for 30 min. The aerosol is then
removed through a closed suction system. Applying an aerosol in the peritoneal cavity allows a
homogeneous distribution of the chemotherapeutic agent within the abdomen. Furthermore an
artificial pressure gradient is generated that overcomes tumoral interstitial fluid pressure
an obstacle in cancer therapy. This results in a higher local drug concentration compared to
conventional IP or IV chemotherapy. At the same time the plasma concentration of the
chemotherapeutic agent remains low. In first clinical studies with limited number of patients
in ovarian gastric and colorectal cancer as well as peritoneal mesothelioma PIPAC has
obtained encouraging tumor response rates and survival with a low-side effects profile. Larger
clinical trials are currently ongoing to examine if these data can be reproduced and
extrapolated to other situations.
