A Minimum Of 100 Tumor Cells in a Single Biopsy Sample Is Required to Assess Programmed Cell Death Ligand 1 Expression in Predicting Patient Response to Nivolumab Treatment in Nonsquamous Non-Small Cell Lung Carcinoma.

Programmed death ligand 1 (PD-L1) expression is a predictive biomarker for patient response to nivolumab in nonsquamous NSCLC. However, the number of biopsy samples and tumor cells (TCs) required to assess PD-L1 expression remains unclear. A total of 222 biopsy samples from 80 patients with nonsquamous NSCLC treated with nivolumab were collected. Number of TCs and PD-L1 score were compared among the sample containing the largest number of TCs (Max-TC), the sample containing the smallest number of TCs (Min-TC), and the total samples from each patient. The impact of the number of samples and TCs on the prediction of patient response to nivolumab with use of PD-L1 scores was evaluated. There was a mismatch in PD-L1 scores less than 1% and those of at least 1% between Max-TC and the total samples in one patient (1%) and between Max-TC and Min-TC in six patients (8%). The optimal number of TCs to match PD-L1 expression less than 1% versus at least 1% between Max-TC and Min-TC was 100 (sensitivity = 0.676 and 1 - specificity = 0.333). PD-L1 expression of at least 1% in Min-TCs containing at least 100 TCs was associated with longer progression-free survival (median 7.6 versus 1.8 months [p < 0.01]) and overall survival (median not reached versus 9.9 months [p = 0.04]) compared with PD-L1 expression less than 1%. However, there were no differences in progression-free survival (median 3.9 versus 2.3 months [p = 0.37]) or overall survival (median 9.7 versus 7.6 months [p = 0.60]) between PD-L1 expression of at least 1% and PD-L1expression less than 1% in Min-TCs containing fewer than 100 TCs. Single biopsy samples containing at least 100 TCs are required to evaluate PD-L1 expression for predicting patient response to nivolumab.

Naito T ，Udagawa H ，Sato J ，Horinouchi H ，Murakami S ，Goto Y ，Kanda S ，Fujiwara Y ，Yamamoto N ，Zenke Y ，Kirita K ，Matsumoto S ，Yoh K ，Niho S ，Motoi N ，Ohe Y ，Ishii G ，Goto K ... -  《-》

Association Between Clinical Tumor Burden and Efficacy of Immune Checkpoint Inhibitor Monotherapy for Advanced Non-Small-Cell Lung Cancer.

Programmed cell death 1 (PD-1) inhibitors have become a standard treatment, albeit not completely effective, for patients with advanced non-small-cell lung cancer (NSCLC). Previous studies of advanced melanoma have revealed that the tumor burden predicted the response to PD-1 inhibitors, although this relationship has remained unclear for NSCLC. The present single-center retrospective study evaluated 163 patients with advanced NSCLC who had received PD-1/programmed cell death ligand 1 (PD-L1) inhibitor monotherapy from December 2015 to December 2018. The clinical tumor burden was estimated using the baseline sum of the target lesions' longest diameters (BSLDs), measured according to the Response Evaluation Criteria for Solid Tumors, and the baseline number of metastatic lesions (BNMLs). The optimal cutoff values for predicting progression-free survival (PFS) were 5 for the BNMLs and 76 mm for the BSLDs, using the minimum P value method. The low-BNML group included 73 patients (44.8%). The median PFS was 12.2 months in the low-BNML group and 2.8 months in the high-BNML group (hazard ratio, 0.51; P = .0005). The low-BSLD group included 92 patients (56.4%). The median PFS was 9.6 months in the low-BSLD group and 3.4 months in the high-BSLD group (hazard ratio, 0.52; P = .0006). Multivariable analysis revealed that low-BSLD, low-BNML, nonsquamous histologic type and a PD-L1 tumor proportion score of ≥ 50% were independently associated with prolonged PFS. PD-L1 expression and the clinical tumor burden can predict the efficacy of PD-1/PD-L1 inhibitor monotherapy for NSCLC.

Miyawaki T ，Kenmotsu H ，Mori K ，Miyawaki E ，Mamesaya N ，Kawamura T ，Kobayashi H ，Omori S ，Wakuda K ，Ono A ，Naito T ，Murakami H ，Harada H ，Endo M ，Ohde Y ，Takahashi K ，Takahashi T ... -  《-》

Outstanding clinical efficacy of PD-1/PD-L1 inhibitors for pulmonary pleomorphic carcinoma.

We evaluated programmed death ligand 1 (PD-L1) expression and efficacy of PD-1/PD-L1 inhibitors in patients with pulmonary pleomorphic carcinoma (PC). We created two cohorts of patients diagnosed with pulmonary PC from 2016 to 2019, PD-L1 expression and programmed death 1 (PD-1)/PD-L1 inhibitor efficacy cohorts. The PD-L1 expression cohort included all patients evaluated for PD-L1 expression, irrespective of PD-1/PD-L1 inhibitor therapy. High PD-L1 expression was defined as ≥50% positive tumour cells (TC) for 22C3, ≥25% for SP263 or ≥10%/5% TC/immune cell (IC) for SP142. The PD-1/PD-L1 efficacy cohort included patients treated with PD-1/PD-L1 inhibitors, irrespective of PD-L1 tests. One hundred twenty-five of 175 patients diagnosed with pulmonary PCs were included in the PD-L1 expression cohort. Among them, 112 patients (89.6%) had PD-L1-positive (≥1%) tumours and 100 (80.0%) had tumours with high PD-L1 expression. A total of 49 patients were included in the efficacy cohort: 40 received pembrolizumab, 7 nivolumab and 2 atezolizumab. The objective response rate was 49.0%, with a median progression-free survival (PFS) of 7.2 months and a median overall survival of 22.2 months. In the efficacy cohort, high PD-L1 expression (n = 41) was associated with longer PFS (median: 7.2 versus 1.5 months, hazard ratio [HR]: 0.53 [0.22-1.29], p = 0.16) and overall survival (median: 22.2 versus 3.5, HR: 0.21 [0.08-0.57], p = 0.001) than low/negative/unknown PD-L1 expression (n = 8). PD-1/PD-L1 inhibitors show outstanding efficacy for pulmonary PCs, and this is possibly attributable to high PD-L1 expression in these tumours.

Lee J ，Choi Y ，Jung HA ，Lee SH ，Ahn JS ，Ahn MJ ，Park K ，Sun JM ... -  《-》

Tumor expression and usefulness as a biomarker of programmed death ligand 1 in advanced non-small cell lung cancer patients with preexisting interstitial lung disease.

Shibaki R ，Murakami S ，Matsumoto Y ，Goto Y ，Kanda S ，Horinouchi H ，Fujiwara Y ，Yamamoto N ，Motoi N ，Kusumoto M ，Yamamoto N ，Ohe Y ... -  《-》

Outcomes to first-line pembrolizumab in patients with non-small-cell lung cancer and very high PD-L1 expression.

In non-small-cell lung cancers with programmed death-ligand 1 (PD-L1) expression on ≥50% of tumor cells, first-line treatment with the PD-1 inhibitor pembrolizumab improves survival compared with platinum-doublet chemotherapy. Whether higher PD-L1 levels within the expression range of 50%-100% predict for even greater benefit to pembrolizumab is currently unknown. In this multicenter retrospective analysis, we analyzed the impact of PD-L1 expression levels on the overall response rate (ORR), median progression-free survival (mPFS), and median overall survival (mOS) in patients who received commercial pembrolizumab as first-line treatment of non-small-cell lung cancer (NSCLC) with a PD-L1 expression of ≥50% and negative for genomic alterations in the EGFR and ALK genes . Among 187 patients included in this analysis, the ORR was 44.4% [95% confidence interval (CI) 37.1% to 51.8%], the mPFS was 6.5 months (95% CI 4.5-8.5), and the mOS was not reached. The median PD-L1 expression level among patients who experienced a response to pembrolizumab was significantly higher than among patients with stable or progressive disease (90% versus 75%, P < 0.001). Compared with patients with PD-L1 expression of 50%-89% (N = 107), patients with an expression level of 90%-100% (N = 80) had a significantly higher ORR (60.0% versus 32.7%, P < 0.001), a significantly longer mPFS [14.5 versus 4.1 months, hazard ratio (HR) 0.50 (95% CI 0.33-0.74), P < 0.01], and a significantly longer mOS [not reached versus 15.9 months, HR 0.39 (95% CI 0.21-0.70), P = 0.002]. Among patients with NSCLC and PD-L1 expression of ≥50% treated with first-line pembrolizumab, clinical outcomes are significantly improved in NSCLCs with a PD-L1 expression of ≥90%. These findings have implications for treatment selection as well as for clinical trial interpretation and design.

Aguilar EJ ，Ricciuti B ，Gainor JF ，Kehl KL ，Kravets S ，Dahlberg S ，Nishino M ，Sholl LM ，Adeni A ，Subegdjo S ，Khosrowjerdi S ，Peterson RM ，Digumarthy S ，Liu C ，Sauter J ，Rizvi H ，Arbour KC ，Carter BW ，Heymach JV ，Altan M ，Hellmann MD ，Awad MM ... -  《-》