There has been an exciting new development in the treatment of one of the most aggressive forms of peritoneal mesothelioma.
Biphasic mesothelioma is a variant of malignant mesothelioma that is even less responsive to standard cancer treatments than the more common epithelioid subtype.
Many studies of peritoneal mesothelioma treatment have focused on people with the epithelioid form of the asbestos cancer, but much less is known about the most effective ways to treat people with biphasic mesothelioma.
Now, a multicenter, international research study suggests that a treatment protocol that has extended survival in epithelioid peritoneal mesothelioma patients may do the same for biphasic patients.
CRS/HIPEC Treatment for Peritoneal Mesothelioma
The treatment, known as cytoreductive surgery (CRS) with heated intraperitoneal chemotherapy (HIPEC), involves surgically removing as much of the peritoneal mesothelioma tumor as possible, then rinsing the body cavity with chemotherapy drugs to prevent new tumors from forming.
The approach has improved the odds of survival in people with peritoneal mesothelioma and, in many centers, has become the standard treatment for otherwise healthy patients with the epithelioid form.
But according to a retrospective analysis of the Peritoneal Surface Oncology Group International registry, half of patients with biphasic peritoneal mesothelioma who had a complete resection lived at least five years after the procedure – only 15 percent fewer than those with epithelioid mesothelioma.
The analysis included data from 33 different cancer centers and 1,165 CRS/HIPEC procedures.
Analyzing Mesothelioma Survival Statistics after CRS/HIPEC
The completeness of the mesothelioma tumor removal during surgery had a significant impact on mesothelioma survival afterward, regardless of which subtype a patient had.
With the more complete resection (CC0), 64.5 percent of epithelioid mesothelioma patients were still living 5 years later whereas 50.2 percent of biphasic patients were alive.
When patients whose resections were a little less than complete (CC1) were included in the analysis, the survival rates dropped a little to 62.9 for epithelioid mesothelioma and 41.6 percent for biphasic. Having chemotherapy (called adjuvant chemotherapy) prior to surgery did not appear to impact survival.
Biphasic Mesothelioma Should Not Rule Out Surgery
Although biphasic mesothelioma patients may still face an even tougher battle than those with epithelioid mesothelioma, the researchers conclude that surgery can still be an option for them.
“Long-term survival is achievable in patients with low-volume biphasic mesothelioma after complete macroscopic cytoreduction,” writes lead study author Konstantinos I. Votanopoulos MD, PhD, FACS, of Wake Forest Baptist Health in North Carolina. “Biphasic peritoneal mesotheliomas should not be considered as an absolute contraindication for CRS/HIPEC if there is low-volume disease and if complete cytoreduction can be achieved.”
Washington Cancer Institute surgeon Paul Sugarbaker, MD, one of the country’s most noted authorities on peritoneal mesothelioma and the developer of the CRS/HIPEC approach, is second author on the paper, which appears in the newest issue of the Annals of Surgical Oncology.
Votanopoulos, KI, et al, “Is Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy Justified for Biphasic Variants of Peritoneal Mesothelioma? Outcomes from the Peritoneal Surface Oncology Group International Registry”, December 19, 2017, Annals of Surgical Oncology, Epub ahead of print