For patients diagnosed at an earlier stage with minimal metastasis, mesothelioma doctors will typically recommend a combination or multimodal treatment of cytoreductive surgery with HIPEC. The treatments together have seen extended survival and high success rates in many clinical trials and studies so far.
What Is HIPEC?
As suggested by its name, HIPEC is a special type of chemotherapy applied specifically to abdominal or peritoneal cancers, like colorectal cancer and peritoneal mesothelioma. HIPEC is often described as a heated chemotherapy wash. The treatment consists of chemotherapy drugs (usually a combination of two types) heated between 104 – 107 degrees. The wash is then circulated throughout the abdominal cavity.
The HIPEC procedure is generally not used as an individual treatment, but rather as a second step of a combination treatment with cytoreductive surgery. The surgery attempts to debulk and remove as many visible tumors and cancer cells as possible. HIPEC is then applied to kill any remaining cancerous cells that couldn’t be reached in surgery. Many studies have shown HIPEC to be more effective than systemic chemotherapy, since it is more targeted and the drugs are often stronger.
Since the treatment is applied after surgery, it unfortunately isn’t an option for all patients. As mesothelioma or other abdominal cancers become more advanced and reach later stages, the cancer cells have likely metastasized or spread too far to be viable for removal. As such, patients diagnosed at stage 3 or stage 4 mesothelioma likely wouldn’t be candidates for this type of treatment. Also, since the treatment is more specialized, it is only available at a handful of cancer centers around the world, which may require patients to travel for treatment.
If doctors are able to diagnose the disease earlier, however, patients have sometimes seen substantial improvements in their prognosis because the cancer treatment is so effective.
HIPEC Survival Rates for Peritoneal Mesothelioma
There have been numerous studies in the last several years around the efficacy of HIPEC for peritoneal mesothelioma, colon cancer, and other gastric cancers. Overall, researchers have found the treatment to be rather successful among these and other cancers, often with minimal side effects compared to traditional chemotherapy and improved survival rates.
Various clinical trials focused on peritoneal mesothelioma found great success, with one recent study even seeing 100% overall survival in patients with early-stage disease and successful cytoreduction. For patients with slightly more advanced mesothelioma, the researchers saw patients achieve a median survival of about 98 months, with nearly 59 months disease-free. Considering the average prognosis for peritoneal mesothelioma is just six months to one year, these results prove how effective this multimodal treatment can be in select patients.
Other studies have also shown similar success. One report analyzing various clinical trials for a number of malignancies in the peritoneal surface noted a wide range of success. The researchers saw overall survival of 53 months or more for peritoneal mesothelioma patients across a number of studies. They also noted an average 5-year survival rate of 47% – 60%, though other studies have reported even higher survival rates.
This is a great improvement against standard chemotherapy, like cisplatin and pemetrexed. Randomized trials have shown peritoneal mesothelioma patients treated with systemic therapy often only see survival of 12 to about 27 months on average. Further, overall mesothelioma survival rates are significantly poorer, with approximately 9% of patients surviving 5 years or longer.
In general, these and numerous other studies prove that HIPEC in combination with surgery is an effective treatment option.
More Advancements in Chemotherapy
Along with the success of HIPEC, researchers have been working on developing other chemotherapy treatments in the hopes of minimizing some of the severe side effects of traditional adjuvant chemotherapy and further improving prognosis.
One of the most promising recent advancements comes from doctors overseas with a treatment called Pressurized IntraPeritoneal Aerosol Chemotherapy or Thoracal Aerosol Chemotherapy (PIPAC/PITAC). PIPAC is also available for peritoneal mesothelioma, with a similar methodology as HIPEC.
PIPAC is also a targeted chemotherapy application, but unlike HIPEC, doctors deliver the chemotherapy to the abdomen using a pressurized aerosol form. Researchers believe the pressure of the aerosol will enable the chemotherapy treatment to spread throughout the abdomen, much like HIPEC does with the liquid chemotherapy wash.
So far, the treatment is only available in early-phase clinical trials, but researchers noted significant tumor regression in these select patients. Since it’s such an early study, PIPAC and PITAC are also currently only available at a handful of treatment centers, but could have a huge impact on cancer care in the future as testing continues.
Treatments like HIPEC, PIPAC, and immunotherapy have enabled more mesothelioma patients to achieve longer survival than ever before. Hopefully with continued research, more patients can achieve remission and doctors will become closer to finding a cure.