Adding the antibody therapy pembrolizumab to standard care for people with soft tissue sarcoma can significantly improve survival in these patients according to new research.
The study was led by the University Health Network in Toronto and published in The Lancet. It showed that disease-free survival was improved by 39% in high-risk patients with soft tissue sarcoma when added to standard care.
“Soft tissue sarcoma is a rare and complex disease with over 50 different subtypes, which makes it hard to study in large clinical trials,” said first author Yvonne Mowery, associate professor of radiation oncology at the University of Pittsburgh, in a press statement.
“Since we haven’t made much progress in treating these patients for decades, it’s really exciting that this trial shows pembrolizumab can improve outcomes beyond current standard of care for patients with locally advanced disease.”
Soft tissue sarcoma is a rare and very variable type of cancer, which can make it hard to treat. Around 50% of patients who have advanced sarcomas develop untreatable metastases, making it important to intervene with effective treatment at an early stage.
Overall, 143 participants with grade 2 or 3, stage III undifferentiated pleomorphic sarcoma or dedifferentiated or pleomorphic liposarcoma of the extremity and limb girdle were included in the study. These patients were randomly assigned to standard care (preoperative radiotherapy and surgery) or standard care plus pembrolizumab before and after surgery.
Two-year disease-free survival was 52% in the control group and 67% in the pembrolizumab group, a survival increase of 15%. As might be expected, grade 3 or higher adverse events occurred more often in the pembrolizumab group than the control group at 56% vs 31%, respectively.
Pembrolizumab is typically used to treat cancers such as melanoma, lung, head and neck, Hodgkin lymphoma, stomach, cervical, and certain types of breast cancer, but not typically sarcoma.
“Based on our finding that pembrolizumab significantly improved disease-free survival, we hope that more clinicians will start incorporating immunotherapy into their practice for these patients,” said Mowery.
“Given that there are such limited effective options for patients with metastatic disease, our hope is that reducing the number of patients who develop metastases will ultimately lead to improvements in overall survival.”
