A new predictive model may make it easier for cancer doctors to choose the best mesothelioma surgery for each pleural mesothelioma patient.
There are two major surgical approaches for pleural mesothelioma. One involves removal of a lung and the other does not.
Right now, the choice about which surgery to have is based on patient demographics, symptoms, and lab values. Which surgery is most common at the institution may also play a role. Many surgeons have strong opinions about which is the best mesothelioma surgery.
But Harvard researchers say the new predictive model they tested is a better way to stratify mesothelioma patients. Their study suggests that this approach may lead to better treatment outcomes and more accurate clinical trials.
Surgical Treatment of Pleural Mesothelioma
EPP and PD are the two main surgical treatments for pleural mesothelioma. Extrapleural pneumonectomy is the most radical approach. It involves removing one of the lungs along with the pleural lining where the mesothelioma tumor started. Other at-risk tissues in the chest are also removed. The goal is to keep new tumors from forming.
The other type of mesothelioma surgery is pleurectomy with decortication (PD). PD surgery leaves the lungs in place. Surgeons remove the pleural membrane and other at-risk tissues. They also scrape away any visible cancer from the surface of the lungs.
Surgeons around the world are divided over which is the best mesothelioma surgery. Some patients live longer after EPP. Others have better survival odds with PD. The Harvard study sheds some light on why this is and how the understanding could improve outcomes.
The Best Mesothelioma Surgery May Hinge on Molecular Factors
The Harvard research team used a variety of tests that focus on the mesothelioma tumor tissue. The tissue came from nearly 400 patients who underwent either EPP or PD between 2007 and 2014.
“The Mesothelioma Prognostic Test (MPT) and molecular subtype based on Claudin-15 to Vimentin (C/V) expression ratio are molecular signatures associated with survival,” writes Beow Yeap, whose name appears first on the paper.
The team combined these tests with measurements of tumor volume (TV) and a white blood cell test called the neutrophil-to-lymphocyte ratio (NLR). The result was a more accurate predictive model for each type of mesothelioma surgery.
“MPT, molecular subtype, TV, and NLR were independently prognostic in EPP patients,” writes Dr. Yeap. “In the PD cohort (N=193), MPT poor risk combined with TV>200 cc was associated with triple the risk compared to other subgroups…”
Both the EPP and PD models were more accurate than current predictive tests.
Yeap, B, et al, “Mesothelioma Risk Score: A New Prognostic Pretreatment, Clinical-Molecular Algorithm for Malignant Pleural Mesothelioma”, July 6, 2021, Journal of Thoracic Oncology, Online ahead of print, https://www.jto.org/article/S1556-0864(21)02255-3/pdf