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Immune Checkpoint Inhibitor Uptake in Real-World Patients With Malignant Pleural Mesothelioma
Roger Y Kim1, Nandita Mitra2, Stephen J Bagley3
1Division of Pulmonary, Allergy and Critical Care, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
Introduction:
Since the July 2017 National Comprehensive Cancer Network (NCCN) malignant pleural mesothelioma (MPM) guideline revision recommended second-line immune checkpoint inhibitors (ICIs), studies have suggested a greater response to ICI among patients with nonepithelioid MPM. Nevertheless, little is known regarding adoption of ICI in routine practice and if uptake differs by histologic subtype. Our objectives were to evaluate the real-world uptake of second-line ICI among patients with MPM and to reveal its association with histologic subtype.
Methods:
This was a multicenter, retrospective cohort study of real-world patients with MPM receiving at least two lines of systemic therapy between 2011 and 2019. We found the uptake of second-line ICI over time and evaluated the association between histologic subtype and ICI use, adjusting for relevant patient demographic and clinical factors.
Results:
Among the 426 patients with MPM in our cohort, 310 had epithelioid and 116 nonepithelioid histologic subtype. The median age was 73 years (interquartile range: 67-78). Overall, 144 patients (33.8%) received second-line ICI and 282 (66.2%) traditional chemotherapy. ICI uptake began in early 2015 before the NCCN guideline revision and increased rapidly to 2019. After the 2017 NCCN guideline revision, patients with nonepithelioid MPM histologic subtypes had more than 3 times the odds of receiving second-line ICI (OR = 3.26; 95% confidence interval: 1.41-7.54).
Conclusions:
Among real-world patients with MPM, second-line ICI uptake began over two years before the 2017 NCCN guideline recommendations and was associated with nonepithelioid histologic subtype after contemporary studies suggested increased clinical benefit in this population, reflecting prompt integration of scientific discovery into clinical practice.
Insights
Second-line immune checkpoint inhibitors (ICIs) for malignant pleural mesothelioma (MPM) were adopted before 2017 guidelines. Uptake was higher for nonepithelioid MPM, reflecting prompt integration of research findings into clinical practice.
Area of Science:
- Oncology
- Clinical Practice
Background:
- National Comprehensive Cancer Network (NCCN) guidelines updated in July 2017 to recommend second-line immune checkpoint inhibitors (ICIs) for malignant pleural mesothelioma (MPM).
- Studies suggested improved ICI response in nonepithelioid MPM, but real-world adoption and differences by histology were unclear.
Purpose of the Study:
- To evaluate the real-world uptake of second-line ICIs in MPM patients.
- To determine if ICI uptake differs by MPM histologic subtype.
Main Methods:
- Multicenter, retrospective cohort study.
- Included MPM patients receiving at least two lines of systemic therapy (2011-2019).
- Analyzed ICI uptake over time and association with histologic subtype, adjusting for covariates.
Main Results:
- 33.8% of 426 MPM patients received second-line ICI; 66.2% received traditional chemotherapy.
- ICI uptake started in early 2015 and increased rapidly through 2019.
- Post-2017 NCCN guideline revision, nonepithelioid MPM patients had >3x odds of receiving second-line ICI (OR=3.26).
Conclusions:
- Second-line ICI uptake in MPM commenced over two years before 2017 NCCN recommendations.
- ICI use was associated with nonepithelioid histology, aligning with suggested clinical benefits.
- This reflects rapid integration of scientific evidence into clinical practice for MPM treatment.
