Is the Lung Immune Prognostic Index Associated With Checkpoint Inhibitor Outcomes in NSCLC?
A recent study examined whether the Lung Immune Prognostic Index (LIPI) was associated with resistance to immunotherapy in patients with advanced non-small cell lung cancer (NSCLC), published in JAMA Oncology (online January 11, 2018; doi:10.1001/jamaoncol.2017.4771).
Prior studies have shown derived neutrophils/(leukocytes minus neutrophils) ratio (dNLR) and lactate dehydrogenase (LDH) level to be associated with immune checkpoint inhibitor outcomes in patients with melanoma. However, their potential association with NSCLC outcomes have yet to be determined.
A group of international researchers led by Laura Mezquita, MD, medical oncology department, Gustave Roussy (France), conducted a study to determine whether pretreatment dNLR and LDH are associated with resistance to immune checkpoint inhibitors in patients with advanced NSCLC. The multicenter retrospective study included a test (n = 161 patients) and a validation set (n = 305) treated with programmed death 1/programmed death ligand 1 (PD-1/PD-L1) inhibitors, as well as a control cohort (n = 162) treated with chemotherapy alone.
A LIPI based on dNLR greater than 3 and LDH greater than upper limit of normal was developed. The primary endpoint was overall survival (OS), and secondary endpoints included progression-free survival (PFS) and disease control rate (DCR).
Results of the study showed that in the test cohort, median PFS and OS were 3 months (95% CI, 2-4) and 10 months (95% CI, 8-13), respectively. A dNLR greater than 3 and LDH greater than upper limit of normal were independently associated with OS (HR, 2.22; 95% CI, 1.23-4.01 and HR, 2.51; 95% CI, 1.32-4.76, respectively).
Researchers reported that median OS for poor, intermediate, and good LIPI was 3 months, 10 months, and 34 months, respectively. Median PFS was 2.0 months, 3.7 months, and 6.3 months, respectively.
Furthermore, DCR was reportedly associated with dNLR greater than 3 and LDH greater than upper limit of normal. Results were reproducible in the immune checkpoint inhibitor validation cohort for OS, PFS, and DCR, but were not significant in the chemotherapy cohort.
Dr Mezquita and colleagues concluded that poor baseline LIPI correlates with worse outcomes for immune checkpoint inhibitor treatment in patients with advanced NSCLC, but not with chemotherapy. LIPI may be a useful tool for selecting immune checkpoint inhibitor treatment and for identifying patients unlikely to benefit from such treatment, they added.—Zachary Bessette