New research shows a breath test called an eNose might help doctors determine which mesothelioma patients are most likely to respond to immunotherapy.
Immunotherapy is one of the most promising new approaches to malignant mesothelioma. But not every patient responds.
A new Dutch study suggests that biomarkers in a patient’s exhaled breath may be indicators of immunotherapy response. The eNose breath test can identify those biomarkers quickly and easily. The technology might make it easier to decide on the best mesothelioma treatment.
Immunotherapy for Malignant Mesothelioma
Pleural mesothelioma is a rare but deadly cancer of the lung lining. Until last year, chemotherapy with Alimta (pemetrexed) was the only FDA-approved systemic treatment.
In 2020, the FDA approved a combination of immunotherapy drugs for mesothelioma. Nivolumab (Opdivo) is an immunotherapy drug that blocks the action of the tumor-protecting protein PD-1. Ipilimumab (Yervoy) blocks a different protein called CTLA4.
Together, these two drugs seem to slow mesothelioma tumor growth in some patients. They are most effective in patients who overexpress the target proteins. But even in these patients, they don’t always work.
Mesothelioma survival depends on choosing the right therapy as early as possible. To make the best decision, doctors need a reliable way to predict which patients will respond to immunotherapy.
Looking for Response Predictors with a Breath Test
The new breath test study took place at the University of Amsterdam. It focused on 31 patients with recurrent pleural mesothelioma. All of these patients received the newly-approved mesothelioma immunotherapy treatment.
Patients had a breath test before they started treatment, and again six months later. Researchers compared the test results of the 16 patients who did respond with those of the 15 patients who did not.
The research team used the Response Evaluation Criteria in Solid Tumors (RECIST) to score each patient’s response.
“At baseline, breath profiles significantly differed between responders and non-responders,” writes lead author Maria Disselhorst.
The eNose breath test measures volatile organic compounds (VOCs) in the exhaled breath. VOCs can provide information about cellular metabolism and the presence of disease. Disselhorst and her colleagues conclude that it can accurately predict which patients are likely to respond to mesothelioma immunotherapy.
“An eNose is able to discriminate at baseline between responders and non-responders to nivolumab plus ipilimumab in MPM, thereby potentially identifying a subgroup of patients that will benefit from ICI [immune checkpoint inhibitor] treatment,” concludes the report.
Previous studies have found the eNose breath test to be 74% accurate at distinguishing between people with mesothelioma and other asbestos-related conditions.
Disselhorst, M, et al, “Nose in malignant mesothelioma-Prediction of response to immune checkpoint inhibitor treatment”, June 1, 2021, European Journal of Cancer, Online ahead of print, https://linkinghub.elsevier.com/retrieve/pii/S0959804921002707
Lamote, K, et al, “Breath analysis by gas chromatography-mass spectrometry and electronic nose to screen for pleural mesothelioma: a cross-sectional case-control study”, September 27, 2017, Oncotarget, pp. 91593-91602, https://www.oncotarget.com/article/21335/text/