Peritoneal Mesothelioma Prognosis Improves with More Tumor Removal Before Chemotherapy

The survival prognosis for diffuse malignant peritoneal mesothelioma is poor. But researchers at the Institute for Cancer Care at Mercy Medical Center in Baltimore think improving it is possible.

The way malignant peritoneal mesothelioma is often treated is with cytoreductive surgery, followed by hyperthermic intraperitoneal chemotherapy.

The researchers have come to believe that this combined treatment can be more effective — and yield a better survival prognosis — if extra effort is made to cut the tumor completely out.

That’s not always possible. But the fewer bits of tumor left behind, the better the chemotherapy that comes right after will work, the researchers explain.

They offered proof of this in a recent study they published in the journal American Surgeon.

Surgical Debulking Makes Chemo Work Better

Diffuse malignant peritoneal mesothelioma spreads quickly across the lining separating the abdominal organs from the inner wall of the abdomen. Consequently, it proves difficult to attack and knock down.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy are considered to be the best therapies available right now for treating diffuse malignant peritoneal mesothelioma.

The goal of cytoreductive surgery is to reduce the number of cancer cells present before treating the patient with chemotherapy. The idea is that surgical debulking makes the remaining tumor cells easier to knock out with the hyperthermic chemo drugs.

Hyperthermic intraperitoneal chemotherapy entails delivering a mildly heated cocktail of chemotherapy drugs into the abdomen — and only the abdomen. This is different from conventional chemotherapy, which is delivered to the whole body.

Because hyperthermic intraperitoneal chemotherapy is confined to just the abdomen, the potency of the drugs can be increased well above what could be tolerated if delivered to the whole body.

As a result of the higher potency, it isn’t necessary to let the drugs remain inside the abdomen until they naturally dissipate. They can be withdrawn after a short time.

The beauty of this is it cuts down on the side effects of chemotherapy.

Peritoneal Mesothelioma Patients Participated in Chemo Study

The Mercy Medical Center researchers’ study into cytoreductive surgery and hyperthermic intraperitoneal chemotherapy was based on a retrospective analysis of diffuse malignant peritoneal mesothelioma patients.

Specifically, they examined the records of 389 patients who had undergone the tandem therapy. From this group the researchers were able to identify 23 patients whose cases were of particular interest.

Each of these 23 suffered diffuse malignant peritoneal mesothelioma and received cytoreductive surgery and hyperthermic intraperitoneal chemotherapy at some point between 1999 and 2014.

The researchers characterized the members of this cohort by sex, age at diagnosis, age at surgery, surgery history, treatment follow-ups, peritoneal cancer index score, completeness of cytoreduction, pathology and overall survival.

They also calculated which of those characteristics were most likely to give doctors an idea of how much survival time a patient could expect after undergoing the two procedures.

Here is some of what they uncovered in the course of their analysis:

  • Mean follow-up time from surgery was 31 months.
  • The median peritoneal cancer index score was 28, with 77 percent of the patients having a score of at least 20.
  • Completeness of cytoreduction was achieved in 65 percent of the cases — and this turned out to be the only factor that offered significant prognostic value.

The title of the researchers’ article is “Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Mesothelioma: Experience of a Peritoneal Surface Malignancy Center.”