Italian doctors are reporting an “impressive clinical response” in a recently published Keytruda case study. The case is encouraging news for people with advanced malignant mesothelioma.
The case involves a 45-year-old woman with metastatic pleural mesothelioma. Doctors found cancer in her chest, brain, and abdomen. Even after several kinds of chemotherapy, the patient continued to go down hill.
Case Looked Hopeless
The 45-year old woman in the Keytruda case study first went to the doctor because of shortness of breath. Doctors found that she had pleural effusion. This is a build-up of lung fluid that is a common sign of mesothelioma.
The woman received a diagnosis of malignant mesothelioma. The mesothelioma was also in her brain and on the peritoneal membrane in her abdomen.
Like most mesothelioma patients, the woman started chemotherapy with Alimta. The treatment worked for awhile. But eventually her mesothelioma tumor stopped responding. Doctors tried chemotherapy with a different combination of drugs.
“After two cycles, she experienced seizures caused by a brain metastasis,” the doctors wrote. They removed the brain tumor and tried another drug called alectinib.
Keytruda Case Study Shows Power of Immunotherapy
Alectinib did not work either. A month later, mesothelioma spread to the woman’s liver and eventually obstructed her bowel. She stopped treatment and her doctors tried to keep her comfortable. She was receiving nutrition intravenously when they decided to try Keytruda.
In this Keytruda case study, the patient could eat normally again within two weeks.
“Imaging displayed complete response of the brain metastasis, peritoneal carcinosis, bone lesions and mediastinal nodal metastases,” writes lead author Giuseppe Bronte in the journal Lung Cancer. “A partial response was documented in the pleural and pulmonary nodules, with stable liver metastases.”
The patient is still undergoing immunotherapy with Keytruda.
How Does Pembrolizumab Work?
Keytruda is the brand name for pembrolizumab. It is an immune checkpoint inhibitor that blocks a protein called PD-L1. PD-L1 helps cancers like non-small cell lung cancer and malignant mesothelioma hide from the immune system.
The good response in this Keytruda case study stems from the fact that the patient tested positive for PD-L1. Her doctors say pembrolizumab may help even in advanced cancer.
“The impressive clinical response obtained by our patient suggests that immune checkpoint inhibitors could help in the management of the disease after the failure of other treatments,” they write.
Keytruda is the most talked-about in a growing field of immunotherapy treatments for mesothelioma.
Bronte, G, et al, “Impressive clinical response to anti-PD-1 therapy in epithelioid mesothelioma with high clonal PD-L1 expression and EML4-ALK rearrangement”, February 14, 2020, Lung Cancer, Epub ahead of print