Peritoneal carcinomatosis or peritoneal metastasis is a stage of advanced cancer that occurs when cancer cells spread throughout the peritoneum, the membrane lining the abdominal cavity and abdominal internal organs.
The combination of systemic chemotherapy, intraperitoneal chemotherapy and surgery has improved the prognosis of carcinomatosis in recent decades. Among the most prominent treatments, cytoreductive surgery combined with the administration of hyperthermic intraperitoneal chemotherapy (HIPEC) is an effective alternative for patients with a limited extent of disease. When the patient is not a candidate for cytoreductive surgery and HIPEC, the alternative is systemic chemotherapy and some advanced intaeperitoneal therapy techniques such as PIPAC or ePIPAC.
What is HIPEC?
HIPEC is a treatment for patients with advanced cancer, which has spread through the peritoneum.
The intervention is performed after completing cytoreductive surgery and consists of the administration of chemotherapy at a temperature between 40-43ºC for a specific time, between 60-120 minutes.
The hot chemotherapy dose is administered in the form of a perfusion, which is removed from the abdomen at the end of the operation. The aim is to eliminate any tumor cells that may be free in the abdomen after surgery.
Which patients can be treated with Cytoreduction Surgery and HIPEC?
Patients with peritoneal carcinomatosis or peritoneal metastases, whose primary tumor may be located in:
Abdomen
– Ovaries
– Stomach
– Appendix (one of its variants is peritoneal pseudomyxoma)
– Colon
– Small Intestine
– Pancreas
– Endometrium,
– Appendix (one of its variants is peritoneal pseudomyxoma)
– Sarcoma
– Cholangiocarcinoma
– Kidney cancer
Outside the abdomen
– Lung cancer
– Breast cancer
– Melanoma
In the peritoneum itself
– Peritoneal mesothelioma
– Primary peritoneal cancer
What is PIPAC?
Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is indicated in patients with peritoneal carcinomatosis of any origin where cytoreductive surgery cannot be performed because the disease is too extensive or because it affects unresectable areas.
By means of laparoscopic surgery under general anesthesia, chemotherapy is applied in the form of an aerosol or spray and with pressure. This technique improves the penetration of chemotherapy into the tumor nodules, without the chemotherapy passing into the blood (or a minimal amount).
Tumor response rate and slowing of tumor progression has been demonstrated and prolonged survival seems likely in patients who have benefited from this new procedure. Fortunately, this minimally invasive procedure is associated with a low rate of side effects and acceptable surgical risks.
Which patients can be treated with PIPAC?
Patients with cancer that has spread to the peritoneum, who are not candidates for HIPEC because of the advanced stage of the cancer and are resistant to chemotherapy.
Comparison between HIPEC and PIPAC
Efficacy
The efficacy of HIPEC varies according to different factors:
- Peritoneal carcinomatosis index (PCI)
- Type of primary tumor
- Stage of the disease
- Completeness of cytoreduction
PIPAC: approximately 16% of patients treated with PIPAC have such a significant response that they may end up being treated with surgery and HIPEC.
Invasiveness
HIPEC is administered after cytoreduction surgery, which can be performed either by conventional open surgical approach or by minimally invasive laparoscopic approach.
PIPAC is a minimally invasive procedure, very well tolerated by patients. By means of laparoscopic surgery under general anesthesia, the abdomen is accessed with 2 or 3 incisions of 1 cm in diameter.
Time and recovery
After cytoreduction surgery and HIPEC, patients may be hospitalized for 7 to 20 days. The normal course of hospitalization begins in the first 24-48 hours, usually in the ICU for close monitoring. Subsequently, the patient is on the ward until he/she is in a suitable condition to return home.
In contrast, after the PIPAC procedure, being minimally invasive, the patient can go home the next day.
Long-term results
At present, treatments for peritoneal carcinomatosis remain limited. Standard palliative chemotherapy often provides only modest improvement in prognosis with low tumor response rates. In addition, this treatment is associated with a significant risk of harmful side effects.
Multimodality management combining systemic chemotherapy – complete cytoreduction surgery and HIPEC – is an effective alternative for patients with disease of limited extent, and which does not affect areas known to be unresectable.
According to data published in the prestigious journal The Lancet, the percentage of patients with very advanced disease in the peritoneum, who are not candidates for HIPEC due to the advanced stage of the cancer and who are resistant to chemotherapy, in whom a response is achieved with PIPAC, is:
- Up to 88% in ovarian cancer
- Up to 91% of patients with stomach cancer
- Up to 86% of patients with colorectal cancer
- Up to 75% of patients with peritoneal mesothelioma.
In conclusion, both HIPEC and PIPAC represent innovative strategies in the treatment of peritoneal carcinomatosis, each with its own indications. HIPEC, combined with cytoreduction surgery, offers an effective option for patients with limited extent of disease, improving long-term prognosis. On the other hand, PIPAC is presented as an alternative for patients who are not candidates for HIPEC due to the advanced stage of their cancer. PIPAC allows better tolerance and faster recovery, showing promising results in slowing tumor progression and response in several types of cancer. The choice between HIPEC and PIPAC depends on multiple factors, including the stage of the cancer, the extent of the disease and the overall condition of the patient, underlining the importance of a personalized approach in the treatment of peritoneal carcinomatosis.
