Programmed Death Ligand 1 Tumor Proportion Score Research Articles

Use of the 22C3 anti-programmed death-ligand 1 antibody to determine programmed death-ligand 1 expression in cytology samples obtained from non-small cell lung cancer patients.

Pembrolizumab monotherapy is a standard-of-care treatment for the first- and second-line treatment of advanced non-small cell lung cancer with programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) values ≥ 50% and ≥ 1%, respectively. PD-L1 testing with the PD-L1 immunohistochemistry (IHC) 22C3 pharmDx companion assay has been validated on tumor tissue with the Dako Autostainer Link 48 (ASL48). 22C3 anti-PD-L1 antibody-based laboratory-developed tests (LDTs) compatible with other autostainers and cytology samples are essential to support pembrolizumab treatment decisions across institutions globally. ASL48 and BenchMark Ultra LDTs were optimized for the evaluation of cytology samples through comparisons with cell lines with known PD-L1 expression levels (strong, moderate, and negative). The PD-L1 TPS was then evaluated for 70 paired biopsy and cytology samples (bronchial washes, n = 40; pleural effusions, n = 30) with these LDTs. Biopsy and cytology LDT TPS values were also compared with a subset of biopsy samples (n = 37) evaluated with the PD-L1 IHC 22C3 pharmDx assay on the ASL48. Intraclass correlation coefficients of 0.884 to 0.898 were observed for biopsy samples versus cytology samples with the ASL48 and BenchMark Ultra LDTs. Concordance was high, regardless of the TPS cut point (<1% vs ≥ 1% and <50% vs ≥ 50%), sample type (pleural effusion vs bronchial wash), or tumor histology (adenocarcinoma vs squamous cell carcinoma). Concordance was high for each LDT versus the PD-L1 IHC 22C3 pharmDx assay. ASL48 and BenchMark Ultra 22C3 antibody concentrate-based LDTs have been validated for PD-L1 testing in cytology samples, and they will support reliable, high-quality PD-L1 testing across regions globally. Cancer Cytopathol 2018;126:264-74. © 2018 American Cancer Society.

Unique distribution of programmed death ligand 1 (PD-L1) expression in East Asian non-small cell lung cancer.

To determine the proportion and clinical features of programmed death ligand 1 (PD-L1) expression in East Asian non-small cell lung cancer (NSCLC). PD-L1 expression was assessed by immunohistochemistry (IHC) and tumor proportion score (TPS) with the use of PD-L1 IHC 22C3 antibody (Dako North America) in 108 surgically resected lung squamous cell carcinomas (SCC) and 221 lung adenocarcinomas (LUADs), and was correlated with clinical variables, histologic subtypes, and common driver mutations. Positive PD-L1 expression was found in 37 lung SCC (37/108, 34.3%), including 15 cases with TPS ≥50% (15/108, 13.9%) and 22 cases with TPS <50% (22/108, 20.4%). In adenocarcinoma cohort, 9 cases were found PD-L1 expression positive (9/221, 4.1%), including 1 case with TPS ≥50% (1/221, 0.5%) and 8 cases with TPS <50% (8/221, 3.9%). Totally, high PD-L1 expression (TPS ≥50%) was significantly associated with male sex (P=0.026), current/ever smoking history (P=0.008) and SCC subtype (P<0.001). Positive PD-L1 expression (including TPS ≥50% and TPS <50%) in LUAD cohort was significantly associated with male sex (P=0.046), current/ever smoking history (P=0.002), mutation pan-negative status (P=0.038), solid-predominant subtype (P<0.001), large tumor size (P=0.027) and lymph node metastasis (P=0.019). No significant difference was found between PD-L1 high expression group (TPS ≥50%) and low/negative expression group in SCC cohort. This study revealed the unique distribution of PD-L1 expression in East Asian NSCLCs, which is largely different from Western populations. Since the high response rate of pembrolizumab in the treatment of lung cancer patients with PD-L1 TPS ≥50%, this result indicates that prospective PD-L1 expression testing in specific East Asian patients could facilitate decision making for immunotherapy.

Comparison of 22C3 PD-L1 Expression between Surgically Resected Specimens and Paired Tissue Microarrays in Non–Small Cell Lung Cancer

IntroductionThe extent to which intratumoral heterogeneity of programmed death ligand 1 (PD-L1) expression causes discordance of PD-L1 expression between paired samples remains unclear. Here, PD-L1 status was compared between whole sections from NSCLCs and the corresponding tissue microarrays (TMAs) serving as surrogate biopsy specimens. MethodsPD-L1 expression was evaluated by 22C3 immunohistochemistry assay on 190 archival surgical specimens and matched to the TMA results. PD-L1 expression was determined by the tumor proportion score (TPS) and classified as TPS lower than 1%, TPS of 1% to 49%, and TPS of 50% or higher. Agreement statistics were used. ResultsThe percentage of PD-L1 expression on tumor cells differed greatly between individual TMAs and matched surgical specimens. When PD-L1 TPS was adopted, a total of 36 of 190 discordance cases (18.9%) were observed, with a κ-value of 0.630 between paired samples. The TMAs underestimated or overestimated PD-L1 status in 19 of 36 (52.8%) and 17 of 36 (47.2%) of the matched surgical specimens, respectively (p = 0.118). The discordance rate was much lower in cases with a PD-L1 TPS lower than 1% compared with in cases with a TPS of 1% to 49% and TPS of 50% or higher (18.4% versus 56.7% and 43.3%, p < 0.001). When a TPS of 50% or higher was used as the cutoff, the discordance rate of PD-L1 TPS less than 50% was further reduced to 7.5%. Such discrepancies were due mainly to intratumoral heterogeneity of PD-L1 expression and nonsignificant association with clinicopathological features. ConclusionsPD-L1 expression in TMAs correlates moderately well with that in the corresponding surgical specimens, indicating that evaluating PD-L1 expression in diagnostic biopsy specimens could be misleading in defining sensitivity to pembrolizumab treatment yet may be reliable as a way to exclude patients with a PD-L1 TPS less than 50% from first-line pembrolizumab treatment.

Pembrolizumab as first-line therapy for patients with PD-L1-positive advanced non-small cell lung cancer: a phase 1 trial

Pembrolizumab improved survival as first- and second-line therapy compared with chemotherapy in patients with highly programmed death ligand 1 (PD-L1) expressing advanced non-small cell lung cancer (NSCLC). We report the long-term safety and clinical activity of pembrolizumab as first-line therapy for patients with advanced NSCLC and the correlation between PD-L1 expression and efficacy. In the open-label phase 1b KEYNOTE-001 trial, treatment-naive patients with advanced NSCLC whose tumors expressed PD-L1 (≥1% staining, assessed using a prototype assay) were randomly assigned to intravenous pembrolizumab 2 or 10 mg/kg every 3 (Q3W) or 2 (Q2W) weeks. Response was assessed per central RECIST v1.1 every 9 weeks in all patients who received ≥1 pembrolizumab dose. Using pre-treatment tumor tissue, a clinical assay quantified the percentage of tumor cells expressing PD-L1 as tumor proportion score (TPS). Between 1 March 2013 and 18 September 2015, 101 patients received pembrolizumab 2 mg/kg Q3W (n = 6), 10 mg/kg Q3W (n = 49), or 10 mg/kg Q2W (n = 46). Of these, 27 (26.7%) had TPS ≥50%, 52 (51.5%) had TPS 1%-49%, and 12 (11.9%) had TPS <1%. The objective response rate (ORR) was 27% (27/101, 95% CI 18-37) and median overall survival was 22.1 months (95% CI 17.1-27.2). In patients with PD-L1 TPS ≥50%, ORR, 12-month PFS, and 12-month OS were higher [14/27 (51.9%; 95% CI 32%-71%), 54%, and 85%, respectively] than the overall population [27/101 (26.7%; 95% CI 18.4%-36.5%), 35%, 71%]. Pembrolizumab was well tolerated, with only 12 (11.9%) patients experiencing grade 3/4 treatment-related adverse events and no treatment-related deaths. Pembrolizumab provides promising long-term OS benefit with a manageable safety profile for PD-L1-expressing treatment-naive advanced NSCLC, with greatest efficacy observed in patients with TPS ≥50%. KEYNOTE-001 (ClinicalTrials.gov, NCT01295827).

Retrospective Molecular Epidemiology Study of PD-L1 Expression in Patients with EGFR-Mutant Non-small Cell Lung Cancer.

PurposeData are limited on programmed death ligand 1 (PD-L1) expression in epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC).Materials and MethodsWe retrospectively evaluated the relationship between PD-L1 expression and recurrence-free survival (RFS) and overall survival in 319 patients with EGFR-mutant NSCLC who were treated at Samsung Medical Center from 2006 to 2014. Membranous PD-L1 expression on tumor cells was measured using the PD-L1 IHC 22C3 pharmDx antibody and reported as tumor proportion score (TPS). Kaplan-Meier methods, log-rank test, and Cox proportional hazards models were used for survival analysis.ResultsAll patients had ≥1 EGFR mutation—54% in exon 19 and 39% in exon 21. Overall, 51% of patients had PD-L1–positive tumors. The prevalence of PD-L1 positivity was higher among patients with stages II-IV versus stage I disease (64% vs. 44%) and among patients with other EGFR mutations (75%) than with L858R mutation (39%) or exon 19 deletion (52%). PD-L1 positivity was associated with shorter RFS, with an adjusted hazard ratio of 1.52 (95% confidence interval [CI], 0.81 to 2.84; median, 18 months) for the PD-L1 TPS ≥ 50% group, 1.51 (95% CI, 1.02 to 2.21; median, 31 months) for the PD-L1 TPS 1%-49% group, and 1.51 (95% CI, 1.05 to 2.18) for the combined PD-L1–positive groups (TPS ≥ 1%) compared with the PD-L1–negative group (median, 35 months).ConclusionPD-L1 expression is associated with disease stage and type of EGFR mutation. PD-L1 positivity might be associated with worse RFS among patients with surgically treated EGFR-mutant NSCLC.

Correlation between Classic Driver Oncogene Mutations in EGFR, ALK, or ROS1 and 22C3–PD-L1 ≥50% Expression in Lung Adenocarcinoma

IntroductionTargeted somatic genomic analysis (EGFR, anaplastic lymphoma receptor tyrosine kinase gene [ALK], and ROS1) and programmed death ligand 1 (PD-L1) tumor proportion score (TPS) determined by immunohistochemistry (IHC) are used for selection of first-line therapies in advanced lung cancer; however, the frequency of overlap of these biomarkers in routine clinical practice is poorly reported. MethodsWe retrospectively probed the first 71 pairs of patients with lung adenocarcinoma from our institution. They were analyzed for PD-L1 by IHC using the clone 22C3 pharmDx kit (Agilent Technologies, Santa Clara, CA) and evaluated for co-occurrence of genomic aberrations and clinicopathologic characteristics. ResultsSurgical resection specimens, small biopsy (transbronchial or core needle) samples, and cytologic cell blocks (needle aspirates or pleural fluid) were tested. A PD-L1 TPS of at least ≥50% was seen in 29.6% of tumors. Of 19 tumors with EGFR mutations, ALK fluorescence in situ hybridization positivity, or ROS1 fluorescence in situ hybridization positivity, 18 had a PD-L1 TPS less than 50% versus only one tumor with a PD-L1 TPS of at least 50% (p = 0.0073). Tumors with a PD-L1 TPS of at least 50% were significantly associated with smoking status compared with tumors with a PD-L1 TPS less than 50% but were not associated with patient sex, ethnicity, tumor stage, biopsy site, or biopsy type/preparation. ConclusionsPD-L1 IHC can be performed on routine clinical lung cancer specimens. A TPS of at least 50% seldom overlaps with presence of driver oncogenes with approved targeted therapies. Three biomarker-specified groups of advanced lung adenocarcinomas can now be defined, each paired with a specific palliative first-line systemic therapy of proven clinical benefit: (1) EGFR/ALK/ROS1-affected adenocarcinoma paired with a matched tyrosine kinase inhibitor (∼20% of cases), (2) PD-L1–enriched adenocarcinoma (TPS ≥50%) paired with anti–PD-1 pembrolizumab (∼30% of cases), and (3) biomarker-negative (i.e., EGFR/ALK/ROS1/PD-L1–negative) adenocarcinoma paired with platinum doublet chemotherapy with or without bevacizumab (∼50% of cases).