Positive PD-L1 Expression Research Articles

Molecular and Clinicopathological Characteristics of Lung Cancer Concomitant Chronic Obstructive Pulmonary Disease (COPD).

IntroductionChronic obstructive pulmonary disease (COPD) and lung cancer often coexist, but its pathophysiology and genomics features are still unclear.MethodsIn this study, we retrospectively collected lung cancer concomitant COPD (COPD-LC) and non-COPD lung cancer (non-COPD-LC) patients, who performed next generation sequencing (NGS) and had clinicopathological information simultaneously. The COPD-LC data from the TCGA cohort were collected to conduct further analysis.ResultsA total of 51 COPD-LC patients and 88 non-COPD-LC patients were included in the study. Clinicopathological analysis showed that proportion of male gender, older age, and smoking patients were all substantially higher in COPD-LC group than in non-COPD-LC group (all P<0.01). Comparing the genomic data of the two groups in our cohort, COPD-LC had higher mutation frequency of LRP1B (43% vs 9%, P = 0.001), EPHA5 (24% vs 1%, P = 0.002), PRKDC (14% vs 1%, P = 0.039), PREX2 (14% vs 0%, P = 0.012), and FAT1 (14% vs 0%, P = 0.012), which had a relationship with improved tumor immunity. Immunotherapy biomarker of PD-L1 positive expression (62.5% vs 52.0%, P = 0.397) and tumor mutation burden (TMB, median TMB: 7.09 vs 2.94, P = 0.004) also were higher in COPD-LC. In addition, RNA data from TCGA further indicated tumor immunity increased in COPD-LC. Whereas, COPD-LC had lower frequency of EGFR mutation (19% vs 50%, P = 0.013) and EGFR mutant COPD-LC treated with EGFR-TKI had worse progression-free survival (PFS) (HR = 3.52, 95% CI: 1.27–9.80, P = 0.01).ConclusionIn this retrospective study, we first explored molecular features of COPD-LC in a Chinese population. Although COPD-LC had lower EGFR mutant frequency and worse PFS with target treatment, high PD-L1 expression and TMB indicated these patients may benefit from immunotherapy.

Abstract 5200: The incidence and risk factors of hyperprogressive disease(HPD) in non-small cell lung cancer(NSCLC) treated with immune checkpoint inhibitors(ICI)

Abstract Background: HPD is an unexpected rapid acceleration of tumor growth reported for patients treated with ICI. The definition of HPD is not fully established and risk factors are uncertain. Our aim in this study was to find the incidence of HPD as well as its significant clinical and genetic risk factors. Method: A total of 203 patients with NSCLC who received ICI at Northwestern Memorial Hospital during 2008-2020 were included. Tumor growth kinetics (TGK) on immunotherapy and TGK pre-immunotherapy were collected and TGK ratio (TGKR) was calculated. HPD was defined as TGKR≥2. Result: HPD was observed in 16% (n=33) of patients. HPD was significantly associated with high ECOG (3-4 vs 1-2) [OR = 4.52, 95% CI = 1.31 to 16.29, P = 0.01], presence of bone metastasis [OR = 2.51, 95% CI = 1.10 to 5.28, P = 0.01], neutrophils/lymphocyte ratio(NLR) ≥5 [OR = 2.68, 95% CI = 1.24 to 5.81 P = 0.01], thrombocytosis (platelet count &amp;gt;450k) [OR = 5.31, 95% CI = 2.07 to 14.70, P=0.0003], and treatment with PD-L1 inhibitor vs PD-1 inhibitor [OR = 2.14, 95% CI= 0.97 to 4.68, P= 0.068]. HPD was inversely associated with positive PD-L1 expression [OR = 0.34, 95% CI = 0.13 to 0.86, P = 0.01], ICI combined with chemotherapy vs ICI monotherapy [OR = 0.24, 95% CI = 0.055 to 0.97, P=0.04], and positive TTF-1 expression [OR = 0.46, 95% CI = 0.21 to 1.02, P=0.057]. HPD was not associated with histology of NSCLC (adenocarcinoma, squamous cell carcinoma, large cell carcinoma, and large cell neuroendocrine carcinoma), age(&amp;lt;70, ≥70), sex, smoking history, number of metastatic lesions (&amp;lt;3, ≥3), brain metastasis, liver metastasis, brain metastasis before treatment initiation, EGFR mutation, TP53 mutation, BRAF mutation, and TNM staging. Conclusion: The incidence of HPD in NSCLC treated with ICI was consistent with current literature. High NLR and platelet count are suggestive of an immunosuppressive environment that could contribute to the rapid growth of tumors. To our knowledge, this is the first study to report an inverse correlation of PD-L1 expression and TTF-1 expression with HPD. The strength of our study lies in a large number of patients. Further studies on validating risk factors of HPD and exploring their associated mechanisms are warranted. Citation Format: Hyeonseon Kim, Yeun Ho Lee, Chiwoo Song, Leeseul Kim, Min Jeong Kim, Horyun Choi, Jinah Kim, Young Kwang Chae. The incidence and risk factors of hyperprogressive disease(HPD) in non-small cell lung cancer(NSCLC) treated with immune checkpoint inhibitors(ICI) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5200.

Abstract 5098: Genetic and immunologic characteristics of biliary tract cancer patients with LRP1B mutation

Abstract Background: Although the initial clinical results of immune checkpoint inhibitors (ICI) have been obtained in biliary tract cancer (BTC), and previous researches explored potential biomarkers for predicting response to ICI in BTC, and gene LRP1B was found as one of predictive biomarkers. Here we evaluated the mutation information of LRP1B in Chinese patients with BTC, and analyzed the potential explanation for more benefit from ICI treatment in patients with LRP1B mutation. Methods: The formalin-fixed paraffin-embedded specimens of 1324 cancer patients who have underwent next-generation sequencing (NGS) from 2016 to 2021, were included in this study. NGS was performed to detect gene mutation, and tumor mutational burden (TMB) measured by a 733 gene panel. PD-L1 expression detected by using Dako PD-L1 IHC 22C3 pharmDx. Result: The NGS results revealed that 12.76% (169/1324) patients with BTC have LRP1B mutation. Among these 1324 patients, 931 (patients with or without LRP1B mutations were 129 and 802, respectively) patients were available for analysis of TMB level, 820 ((patients with or without LRP1B mutations were 114 and 706, respectively)) patients for analysis of PD-L1 expression, and 1163 (patients with or without LRP1B mutations were 172 and 991, respectively) patients for analysis of MSI-H. TMB level and PD-L1 expression level were compared between groups with and without LRP1B mutation, and results showed that both these two biomarkers were higher in group with LRP1B mutation than without LRP1B mutation, especially TMB level was significantly higher (p&amp;lt;0.001).Further analysis revealed that the median TMB level, proportion of strong positive PD-L1 expression, and proportion of MSI-H were all higher in group of LRP1B mutation than wild type. Conclusion:These results suggest that LRP1B can be considered as one of effective biomarkers for ICI treatment in BTC, the underly mechanism may be related to the high TMB level. Citation Format: Weiwei Chen, Hushan Zhang, Hongmin Dong, Gang Wang, Xiaokai Li, Wanghua Chen, Guodong Li, Saixi Bai, Juan Chen, Wenling Wang. Genetic and immunologic characteristics of biliary tract cancer patients with LRP1B mutation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5098.

Abstract 6122: Different characteristics of tumor immune microenvironment between LUSC and LUAD

Abstract Background: Patients with lung squamous cell carcinoma (LUSC) have higher tumor mutation burden (TMB) and PD-L1 expression than those with lung adenocarcinoma (LUAD). Several studies showed that tumor immune microenvironment (TIME), mainly the tumor-infiltrating immune cells, may affect the efficacy of immunotherapy. However, the comparison of tumor immune microenvironment between LUAD and LUSC is little known. Methods: 14 patients with LUSC and 21 patients with LUAD were enrolled in the retrospective analysis of multiple immunofluorescence staining to assess the number of immune cells. Genomic profiling of DNA was performed on formalin-fixed paraffin-embedded tumor samples from 3752 LUAD and 459 LUSC patients by NGS with 733 cancer-related genes panel. TMB is defined as the total counts of single nucleotide variants and indels in the exon region. Results: Overall, as the most abundant tumor-infiltrating immune cells in both groups, CD3+ cells are more in LUAD [median (number/mm2 in LUSC vs in LUAD): 312 vs 918, p = 0.02]. However, there were no significant differences in CD8+ T cells (median: 48 vs 36, p = 0.74), indicating higher infiltration of T lymphocytes rather than cytotoxic T lymphocytes (CTLs) in LUAD than that in LUSC. Unlike in tumor, LUAD patients had both more T lymphocytes (p &amp;lt; 0.001) and CTLs (p &amp;lt; 0.01) in stroma. Besides, LUSC was correlated with fewer M2 tumor-associated macrophages (TAMs) and PD-1+ immune cells (p &amp;lt; 0.001; p = 0.02), while no significant differences were found in tumor-infiltrating FOXP3+ cells (p = 0.41) and B lymphocytes (p = 0.61). In addition, natural killer cells were the fewest among the tumor-infiltrating lymphocytes detected in both groups (median: 2 vs 13). Similar to the previous studies, TMB level was higher in LUSC (median: 8.94 vs 3.36, p &amp;lt; 0.0001). Although LUSC patients had a larger proportion of positive PD-L1 expression (45% vs 30.5%, p &amp;lt; 0.0001) and strong PD-L1 expression in tumor cells (20.9% vs 10.7%, p &amp;lt; 0.0001), the number of CTLs and TAMs expressing PD-L1 is significantly lower than that in LUAD ( p = 0.04; p = 0.0001). Conclusion: LUAD had more immune invasion, while LUSC was related to higher TMB and PD-L1 expression. It suggested that the mechanisms affecting the benefits of immunotherapy may be different. The immune microenvironment of tumor and stroma should be considered simultaneously to explore the mechanism of immunotherapy and the respective thresholds should be selected according to the types of immune cells. Citation Format: Na Li, Mengna Hu, Ding Zhang, Xiaoyu Ji. Different characteristics of tumor immune microenvironment between LUSC and LUAD [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6122.

Prevalence of Epstein-Barr Virus Infection and Mismatch Repair Protein Deficiency and the Correlation of Immune Markers in Tibetan Patients with Gastric Cancer.

Background Gastric cancer (GC) is a major cause of cancer-related death in China. Immunotherapies based on PD-1/PD-L1 inhibitors have improved the survival of some patients with GC. Epstein–Barr virus (EBV) infection, mismatch repair (MMR) deficiency, and tumor immune microenvironment (TIME) markers (such as CD3, CD8, and PD-L1) may help to identify specific patients who will respond to PD-1/PD-L1 inhibitors. Considering racial heterogeneity, the pattern of TIME markers in Tibetan patients with GC is still unclear. We aimed to identify the prevalence of EBV infection and the MMR status and their association with immune markers in Tibetan GC to aid in patient selection for immunotherapy. Materials and Methods From 2001 to 2015, we retrospectively collected 120 tissue samples from consecutive Tibetan GC patients and constructed tissue microarrays. EBV infection was assessed by Epstein–Barr-encoded RNA (EBER) in situ hybridization, and MMR protein levels were measured. Immune markers (including CD3 and CD8) in intraepithelial, stromal, and total areas were detected by immunohistochemistry (IHC). PD-L1 expression was assessed by the combined positive score (CPS). We also analyzed the relationships of EBV infection and MMR status with immune markers. Results Of the 120 samples, 11 (9.17%) were EBV positive (+), and 6 (5%) were MMR deficient (dMMR). PD-L1 CPS ≥1% was found in 32.5% (39/120) of Tibetan GC patients. EBV infection was associated with higher numbers of CD3+ T cells (P < 0.05) and CD8+ T cells (P < 0.05) and higher PD-L1 expression (P < 0.05). For the limited number of dMMR patients, no significant relationship was observed between dMMR and TIME markers (P > 0.05). Conclusions In Tibetan GC patients, the rates of EBV infection, dMMR, and positive PD-L1 expression were 9.17%, 5%, and 32.5%, respectively. EBV infection was associated with the numbers of CD3+ T cells and CD8+ T cells and PD-L1 expression within the tumor. These markers may guide the selection of Tibetan GC patients for immunotherapy.

Genomic characterization and translational immunotherapy of microsatellite instability-high (MSI-H) in cholangiocarcinoma.

4101 Background: Microsatellite instability-high (MSI-H) status is a unique genomic state with encouraging effects of PD-1-based therapy in patients with advanced cancer. Cholangiocarcinoma is often driven by genetic mutations. However, the genomic characterization and translational medicine of MSI-H are not clear. Methods: In this study, 881 Chinese patients with cholangiocarcinoma (582 intrahepatic cholangiocarcinoma and 299 extrahepatic cholangiocarcinoma) were enrolled and their genomes were investigated using panel sequencing or whole-exome sequencing. Clinicopathological and genomic features as well as PD-1 inhibitor-based immunotherapy were analyzed by MSI status in patients with cholangiocarcinoma. Results: Overall, 47 (5.3%) cholangiocarcinoma patients were identified as MSI-H patients after enrichment enrollment. Intrahepatic cholangiocarcinoma (ICC) accounted for 74.47% (35/47) of MSI-H patients. Clinicopathological parameters showed younger, ICC-dominated, and more positive PD-L1 expression in MSI-H patients. In the genome of MSI-H cholangiocarcinoma, ACVR2A (75.00%), ARID1A (75.0%), KMT2D (72.2%), TGFBR2 (63.9%), PBRM1 (58.3%), RNF43 (55.6%), TP53 (52.8%) ), ARID1B (47.2%) had a higher mutation frequency. Comparing the SNV and INDEL mutation in the genome, the differential genes between MSI-H and MSS were ARID1A, ACVR2A, KMT2D, TGFBR2, PBRM1, RNF43, LRP1B, ARID1B, etc., respectively. In addition, the differential mutation pathways of MSI-H showed that the mutation rate of DDR, SWI/SNF CellCycle, HRD and other pathways was significantly higher than that of MSS samples. The tumor mutation burden (TMB) in MSI-H patients was significantly higher than that in MSS (P&lt;0.001). In a cohort of 151 CCA patients who received PD-1 inhibitor-based immunotherapy, 19 patients with MSI-H cholangiocarcinoma were found to have a favorable prognosis (1-year survival rate 68.4%). Compared with 132 MSS cholangiocarcinoma patients, Patients with MSI-H cholangiocarcinoma had significantly prolonged OS (Not reach vs. 13.4m, P&lt;0.001, HR=0.17, P &lt;0.001) and high clinical benefit (CBR) (OR=8.16, P &lt;0.001). In this immunotherapy cohort, ≥2 DDR pathway genes and ≥2 SWI/SNF pathway genes mutations, positive PD-L1 expression and TMB-H were also associated with better OS and CBR (both P&lt;0.05). Conclusions: MSI-H cholangiocarcinoma has distinct genomic features, and the effect of PD-1 inhibitors immunotherapy is excellent to these patients. Clinical trial information: NCT03892577.

Updated analysis from the ATEZO-BRAIN trial: Atezolizumab plus carboplatin and pemetrexed in patients with advanced nonsquamous non–small cell lung cancer with untreated brain metastases.

9010 Background: Atezolizumab plus chemotherapy was safe and yielded promising clinical outcome as frontline therapy for patients (pts) with advanced NSCLC with untreated brain metastases (BM) in the ATEZO-BRAIN study (NCT03526900). Methods: A multicenter single-arm phase II trial with a Bayesian design for evaluating the safety and efficacy of atezolizumab plus carboplatin with pemetrexed every 3 weeks for 4-6 cycles, followed by maintenance with pemetrexed plus atezolizumab in pts with stage IV non-squamous NSCLC without EGFR or ALK genetic alterations and untreated BM. Pts not presented neurologic symptoms at baseline; but anticonvulsants and dexamethasone (DXM) ≤ 4mg qd were allowed. Co-primary endpoints were safety and investigator-assessed progression-free survival (PFS) at 12 weeks according to RANO-BM and RECIST v1.1 for brain and systemic disease, respectively. Here we present the final data and an exploratory analysis based on PD-L1 expression and corticosteroid treatment at baseline. Results: Out of 40 pts included in the study, 22 (55%) were receiving DXM at baseline and 20 (50%) had positive expression of PD-L1. Sixteen (40%) pts had confirmed intracranial response based on RANO-BM (12 PR, 4 CR) and 19 (47.5%) pts achieved systemic response (all PR). Only 4 pts had discordant responses between the body and the brain. No differences were observed in the overall systemic and intracranial response rate according to the PD-L1 expression or the use of corticosteroids at baseline. As of December 31, 2021 (median follow-up, 20 months), the updated median (95% CI) systemic PFS was 8.9 (6.7 to 13.8) and intracranial PFS was 6.9 (4.7 to 11.9). Median (95% CI) OS was 13.6 (9.72 to not reached) and estimated 2-year OS rate (95% CI) was 30.5% (18.4 to 50.4). Median (95%CI) OS was longer for PD-L1 positive pts (16.2; 10.3 to not reached) compared to PD-L1 negative pts (10.7; 7.6 to not reached) but differences were not statistically significant due to the limited statistical power (HR = 0.99; 95% CI 0.35 to 2.12). No significant differences in OS were observed between pts receiving or not baseline DXM treatment. Treatment was well tolerated and no grade 5 toxicities were observed. Conclusions: In this updated analysis, treatment with atezolizumab plus carboplatin and pemetrexed yields a promising 2-year OS rate and intracranial response rate in patients with untreated BM from NSCLC, regardless of treatment with corticosteroids at baseline and PD-L1 expression. Clinical trial information: NCT03526900.

PD-L1, VISTA, and CD47 expression and prognosis impact in malignant pleural mesothelioma.

8562 Background: Malignant Pleural Mesothelioma (MPM) has been characterized by an immune suppressive microenvironment. The immune checkpoint (IC) VISTA is notably expressed in MPM, in contrast to other IC proteins such us PD-L1. Recently, CD47 has been described as a possible diagnostic biomarker for MPM, although its impact in prognosis has not been established yet. Methods: This is a retrospective observational study of immunotherapy naïve MPM patients. Immunochemistry (IHC) assessment of PD-L1, VISTA and CD47 protein expression was performed on tissue microarray of 46 surgical samples. Means were compared using Mann-Whitney U test. Correlation was estimated using Pearson’s coefficients. Overall survival (OS) was assessed using Kaplan–Meier curves and Cox proportional hazard models. A two-sided alpha error of 0.05 was used to assess statistical significance. Statistical analysis was conducted with Stata/SE version 16.1. Results: A total of 46 patients, 71.7% (33/46) male, were included in our study. Among them, 77.8% (35/45) had stage IIIB-IV, 84.8% (39/46) had received systemic therapy and 16.7% (7/42) had undergone radical-intent surgery. Asbestos exposure was confirmed in 65,7% (23/35) patients. Regarding the histological subtype, 71.7% (33/46) were epithelioid (Ep) and 13.0% (6/46) non-epithelioid (NEp), including 5 sarcomatoid and 1 biphasic. In IHC analysis, VISTA and CD47 were expressed in 63.0% (29/46) and 58.7% (27/46), respectively, whereas only 28.3% (13/46) patients had positive PD-L1 expression (≥1%). Median expression of VISTA, CD47 and PD-L1 in tumor samples was 41.8 (95% IC 0.5 - 50.7), 26.3 (95% IC 0 - 45.8) and 0 (95% IC 0-0.5), respectively. VISTA and CD47 expression were significantly higher in the Ep subgroup vs. the NEp subgroup (VISTA 39.4% vs 7.2% p = 0.028; CD47 37.3 vs. 0.8 p = 0.01). Additionally, we found a significant positive correlation between VISTA and CD47 protein expression (Pearson's r = 0.55, p &lt; 0.001), which was consistent with the results we found in an independent MPM patient series from TCGA PanCancer Atlas (N = 87) based on RNA expression (r = 0.46; p &lt; 0.001). Median OS, available in 40/46 cases, was 16.6 months (95% CI 12.03-20.43). On multivariate analysis, CD47 ≥1% expression was significantly associated with longer OS (29.7 vs 10.53 months, HR 0.35, [IC 95% 0.14-0.86]; p = 0.02) after adjusting for histological subtype, PDL1 and VISTA expression. In contrast, PD-L1 ≥1% showed a trend towards worse prognosis (10.3 vs 19.3 months), without reaching statistical significance (HR 2.23 [95% IC 0.95-5.23]; p = 0.065). No OS differences were found regarding VISTA expression. Conclusions: To our knowledge, this is the first study to describe VISTA and CD47 correlation in MPM. Moreover, we demonstrate CD47 expression to be an independent prognostic marker in MPM, suggesting C47 may play a key role in tumor biology of MPM, for which further validation and functional studies are necessary.

Clinical activity of pembrolizumab monotherapy in diffuse malignant peritoneal mesothelioma.

8557 Background: Among patients with malignant mesothelioma, pembrolizumab has demonstrated activity in diffuse pleural mesothelioma (DPM), with limited data available for those with diffuse malignant peritoneal mesothelioma (DMPM). DMPM represents a clinically distinct entity from DPM and disease specific outcomes data is needed. We present real world data on the efficacy of pembrolizumab in DMPM. Methods: In this retrospective study, we identified patients with DMPM treated with pembrolizumab at two tertiary care cancer centers between 1/1/2009 and 1/1/2021. Clinicopathologic features were annotated. Median progression free survival (mPFS) and median overall survival (mOS) were calculated using Kaplan-Meier curves. Best overall response rate (BOR) was determined using RECIST 1.1 criteria. Association of partial response with disease characteristics was evaluated using Fisher’s exact test. Results: We identified 24 patients with DMPM who received pembrolizumab (median age 62 years, 63% never smokers, 58% female, 75% had epithelioid histology). All patients received systemic chemotherapy prior to pembrolizumab (median prior lines of therapy: 3). BOR was 17% (3 partial responses, 10 stable disease, 5 progressive disease, 6 lost to follow-up). With a median follow up time of 29.2 months, mPFS was 4.9 months and mOS 20.9 months from pembrolizumab initiation. Three patients experienced PFS of &gt; 2 years. Among the 14 patients who underwent next generation sequencing of tumor tissue, there were 8 somatic BAP1 alterations. Among the 17 patients tested for PDL1, 6 had positive PDL1 expression (1-80%). There was no association between partial response and presence of a BAP1 somatic alteration (p = 0.453), PDL1 positivity (p = 0.7) or non-epithelioid histology (p = 0.55). Conclusions: Pembrolizumab is active in a PDL1 unselected cohort of patients with DMPM. The overall response rate of 17% and mPFS of 4.9 months in this 75% epithelioid histology cohort warrants further investigation to identify those most likely to respond to immunotherapy, especially among epithelioid histology.

The incidence and predictive factors of hyperprogressive disease (HPD) in non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICI).

e21025 Background: HPD is an unexpected and rapid acceleration of tumor growth in patients following treatment with ICI. The definition of HPD is not fully established and risk factors are uncertain. Our aim in this study was to find the incidence of HPD as well as its significant clinicopathological and genetic predictive factors. Methods: A total of 203 patients with NSCLC treated with ICI at Northwestern Memorial Hospital during 2015-2020 were included. Clinicopathological data were retrospectively gathered and analyzed. Tumor growth kinetics (TGK) of pre-immunotherapy and post-immunotherapy were collected and TGK ratio (TGKr) was calculated. HPD was defined as TGKr≥2. Results: HPD was observed in 16% (33/203) of patients. There was a statistically significant difference in overall survival(OS) between the two groups (non-HPD vs. HPD) [OR = 2.39, P &lt; 0.01]. The progression-free survival(PFS) also showed a statistically significant difference in patients (non-HPD vs HPD) [OR = 3.4, P &lt; 0.01]. The median OS and PFS of patients with HPD were 13.57 months and 2.2 months respectively. The median OS and PFS of patients without HPD were 30.67 months and 7.3 months respectively. HPD was significantly associated with performance status (3-4 vs. 1-2) [OR = 4.52, P = 0.01], presence of bone metastasis [OR = 2.51, P = 0.01], neutrophils/lymphocyte ratio(NLR) ≥5 [OR = 2.68, P = 0.01], thrombocytosis (platelet count &gt; 450k) [OR = 5.31, P &lt; 0.01], and treatment with PD-L1 inhibitor vs. PD-1 inhibitor [OR = 2.14, P = 0.06]. HPD was inversely associated with positive PD-L1 expression [OR = 0.34, P = 0.01], ICI combined with chemotherapy vs. ICI monotherapy [OR = 0.24, P = 0.04], and positive TTF-1 expression [OR = 0.46, P = 0.06]. HPD was not associated with histological subtypes of NSCLC, age(&lt; 70, ≥70), sex, smoking history, number of metastatic lesions (&lt; 3, ≥3), brain metastasis, liver metastasis, brain metastasis before treatment initiation, EGFR mutation, TP53 mutation, BRAF mutation, TNM staging, tumor mutational burden (TMB) (&lt; 10, ≥10), microsatellite stability index (MSI), human leukocyte antigen-1 (HLA-1) heterozygosity, hemoglobin(≤12, &gt; 12), albumin(≤3.5, &gt; 3.5), and LDH(≤240, &gt; 240). Conclusions: The incidence of HPD, 16%, was consistent with current literature. NLR ≥5, platelet count &gt; 450k, poor performance status, presence of bone metastasis, treatment with PD-L1 inhibitor, negative PD-L1 expression, negative TTF-1 expression, and ICI monotherapy were predictors of HPD. To our knowledge, this is the first study to report an inverse correlation of TTF-1 expression, and non correlation of HLA-1 heterozygosity with HPD. The strength of our study is that we analyzed recently emerging next-generation sequencing (NGS) data to find novel predictors of HPD. Further studies on validating risk factors of HPD and exploring their associated mechanisms are warranted.

A phase II single-center single-arm study of PD-1 inhibitor in combination with albumin paclitaxel and apatinib as second-line treatment of metastatic gastric cancer (mGC).

e16024 Background: Immune checkpoint inhibitors have been approved for first- or third-line treatment of metastatic gastric cancer. However, pembrolizumab alone did not improve overall survival compared to second-line chemotherapy in the KEYNOTE-061 study. We aimed to explore the safety and efficacy of a three-drug regimen by carrying out a clinical study of PD-1 inhibitor combined with albumin paclitaxel and apatinib (VEGFR inhibitor) in the second-line treatment for patients with metastatic gastric cancer(mGC). Methods: This study was a single-center, single-arm phase II clinical study. patients harboring microsatellite stable (MSS) who had previously failed in first-line treatment were enrolled. The enrolled patients were given PD-1 inhibitor (PD-1 inhibitor selected according to the patients’ requirements) in combination with albumin paclitaxel (125 mg/m2 IV, D1, 8 days or 250 mg/m2 IV, D1, 250 mg and apatinib 250 or 500 mg orally for D1-21 days, every 3 weeks as a cycle). The primary endpoints were progression-free survival (PFS) and objective response rate (ORR), while the secondary endpoints were overall survival (OS) and safety (AEs), disease control rate (DCR). Results: From July 11, 2019 to December 1, 2021, a total of 23 patients were enrolled, of whom 10 had negative PD-L1 expression, 1 had PD-L1 &gt; 70% expression, and 4 had positive PD-L1 expression. Preliminary results showed 8 cases had partial response (PR), 10 cases had stable disease (SD), and 5 cases of progression disease (PD). ORR was 34.8% and DCR was 78.3%. The median PFS was 5.04 m, and the median OS was not reached. The main adverse reactions of grade 1 to 2 were bone marrow suppression (42.8%), hand-foot reaction (21.4%), hypertension (21.4%), gastrointestinal bleeding (13.0%), hypothyroidism (8.7%), and liver function damage (8.7%). No grade 3-4 adverse reactions were reported. Conclusions: PD-1 inhibitor combined with albumin paclitaxel and apatinib in the second-line treatment of metastatic gastric cancer showed certain efficacy and safety. At present, this study is ongoing to further confirm the anti-tumor effect and survival benefit of this regimen. Clinical trial information: NCT04182724.

Clinical and genomic characteristics of lung cancer concomitant chronic obstructive pulmonary disease (COPD).

e15131 Background: Lung cancer and chronic obstructive pulmonary disease (COPD) often coexist. Lots of clinical and genomic descriptions related lung cancer have been investigated. However, the clinical and genomics characteristics of lung cancer coexisting COPD are still unclear. Herein, we explored the clinical characteristics and somatic mutational landscape of lung cancer coexisting COPD (COPD-LC) and compared with non-COPD Lung cancer (non-COPD-LC). Methods: We retrospectively collected total COPD-LC and non-COPD-LC patients who performed next generation sequencing (NGS) simultaneously from The Traditional Chinese Medicine Hospital Affiliated to Xinjiang Medical University during December 2018 to August 2021. And collected COPD-LC data from TCGA to further analysis. COPD was defined as incompletely reversible airflow obstruction associated with post-bronchodilator forced expiratory volume in one second (FEV1) and its ratio to forced vital capacity (FEV1/FVC) &lt; 0.7. Results: Of the 139 patients enrolled in the study, 51 were categorized as COPD and 88 as non-COPD. In our clinical cohort, compared with non-COPD-LC, amount of male gender, older age and smoking patients were significantly higher than non-COPD in term of clinical data (all P &lt; 0.01). As for somatic mutation in our cohort, compared with non-COPD-LC, COPD-LC had higher mutation frequency of LRP1B (43% vs 9%, P = 0.001), EPHA5 (24% vs 1%, P = 0.002), PRKDC (14% vs 1%, P = 0.039) and PREX2 (14% vs 0%, P = 0.012), which had relationship with improved tumor immunity. Immunotherapy biomarker of PD-L1 positive expression (62.5% vs 52.0%, P = 0.397) and TMB (P = 0.004) also were higher in COPD group. Whereas, COPD-LC had lower frequency of EGFR (19% vs 50%, P = 0.013). And survival analysis showed in EGFR mutant patients with targeted therapy, COPD-LC had worse PFS than non-COPD-LC (HR = 3.52, 95%CI: 1.27-9.80, P = 0.01). TCGA cohort mutation data differed from the results of our cohort. In addition, RNA data from TCGA indicated COPD-LC increased tumor immunity. Conclusions: In our research, COPD-LC had unique clinical and molecular features. High PD-L1 expression and TMB indicated these patients may benefit from immunotherapy. Notably, mutation difference between Chinese and TCGA cohort and COPD-LC immunotherapy efficacy need prospective further study.

Association of RB1 mutational status with overall genomic landscape in neuroendocrine prostate cancer (NEPC).

5063 Background: NEPC is a high-grade aggressive form of prostate cancer. We queried whether RB1 mutation status would impact the genomic features of NEPC in RB1 mutated vs non-mutated cases. Methods: From a series of 13,496 cases of clinically advanced PC, we identified 415 cases (3.1%) with a diagnosis of small cell PC or NEPC as determined by the submitting physician. They were sequenced using a hybrid capture-based FDA-approved clinical genomic profiling (CGP) assay to detect all classes of genomic alterations (GA). Tumor mutational burden (TMB) was determined on 0.8 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on 95 loci. PD-L1 expression was determined by IHC (Dako 22C3) with low tumor cell positive staining 1-49% and high staining ≥50% expression. Results: 253 (61%) of NEPC feature GA in RB1 (RB1 mut+). This contrasts with a 5.8% frequency of RB1 GA in the non-NEPC (P &lt;.0001). The RB1 mut+ NEPC featured a slightly greater number of pathogenic GA/tumor than the RB1 mut- NEPC (5.1 vs 4.2). Age and TMPRSS2-ERG fusion frequency were similar between the groups. RB1 Mut- NEPC was associated with significantly higher amplifications (amp) and total GA in AR compared to RB1 mut+ NEPC. RB1 mut+ NEPC featured significantly greater frequency of PTEN GA. GA frequencies in targetable kinases and DNA repair GA including BRCA1/2 and ATM linked to PARP inhibitor (PARPi) response were similar in both groups. For potential immune-oncology (IO) biomarkers, RB1 Mut+ NEPC featured significantly greater frequency of positive PD-L1 expression and lower frequencies of MDM2 and CDK12 GA. CD274 ( PD-L1) amplification, MSI-high status and cases with TMB ≥10 mut/Mb were uncommon in both groups. gLOH was higher in RB1 mut+ than RB1 mut- (P =.005). There were more cases of non-European ancestry in the RB1 mut- group. APC I1307K mut were found in 3/162 (1.9%) RB1 mut- NEPC only. Conclusions: In NEPC, the presence of RB1 mutation is associated with various GA that may have clinical relevance. Further study of RB1 status as a guide in trial designs on therapy selection for men with NEPC appears warranted. [Table: see text]

Association of Tumor PD-L1 Expression With Time on Treatment Using EGFR-TKIs in Patients With EGFR-Mutant Non-small Cell Lung Cancer.

The association between tumor PD-L1 expression and the rate of acquisition of the T790M mutation during treatment with first-/second-generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is a matter of study. This retrospective study was conducted to evaluate the association of tumor PD-L1 expression with the time on treatment under EGFR-TKIs in patients with EGFR-mutant non-small cell lung cancer (NSCLC), treated with first-/second-generation EGFR-TKIs. We conducted a retrospective review of the medical charts of patients with EGFR-mutant NSCLC treated with first- /second-generation EGFR-TKIs. Time on treatment with EGFR-TKIs was defined as the sum of progression-free survival period (PFS) from the start of treatment with first- /second-generation EGFR-TKIs and the PFS from the start of osimertinib treatment after acquisition of the T790M mutation. Tumor PD-L1 expression was evaluated using the 22C3 antibody. Data of a total of 49 patients were analyzed, including 20 patients with negative tumor PD-L1 expression (tumor proportion score <1%) and 29 patients with positive tumor PD-L1 expression (tumor proportion score ≥1%). In the negative tumor PD-L1 expression group, the T790M mutation was detected in 12 (75%) of the 16 patients. In the positive tumor PD-L1 expression group, the T790M mutation was detected 6 (31.6%) out of the 19 patients in whom it was tested. The median (95% confidence interval) time on treatment with EGFR-TKIs was 21.7 (12.9-24.8) months and 12.3 (5.6-22.2) months in the negative and positive tumor PD-L1 expression groups, respectively. Analysis using a Cox proportional hazards model identified performance status and presence/absence of tumor PD-L1 expression as significantly associated with the time on treatment with EGFR-TKIs. EGFR-mutant NSCLC patients with negative tumor PD-L1 expression showed a higher rate of acquisition of the T790M mutation and implementation rate of osimertinib therapy, leading to a longer time on treatment with EGFR-TKI.

PD-L1 expression in gastric carcinoma – a biomarker for immunotherapy

Introduction and Aim: Immunotherapy is now being widely used for targeted therapy in several cancers. The PD-1/ PD-L1 (programmed cell death receptor/programmed cell death ligand) axis inhibits the expansion of tumour specific T cells and prevents the immune response against tumours. PD-L1 expression is seen in many cancers including gastric carcinomas and anti PDL1 antibodies are being used to produce tumour regression. This study was done to evaluate PD-L1 expression in gastric carcinomas and correlate this with the different histological types, grades and stages of these tumours Materials and Methods: In this study, 50 cases of gastric adenocarcinoma were analysed for PD-L1 expression using immunohistochemistry. PD-L1 expression was correlated with histopathological factors including histological type, differentiation, grade and stage using statistical methods. Results: A positive PD-L1 expression was observed in 52% of the cases. A positive correlation between PD-L1 positivity and tumour depth to which the tumour was invading the stomach was observed. No correlation was noted with expression of PD-L1 and histological type, differentiation, histological grade and presence/absence of nodal metastasis. Conclusion: PD-L1 expression was seen in more than half of the patients in our study. Hence it is suggested that anti PD-L1 inhibitors can be used as an adjunct in the treatment of gastric cancers, especially those with a greater depth of invasion.

Clinical relevance of pathogenic germline variants in mismatch repair genes in Chinese breast cancer patients

The prevalence and clinical relevance of pathogenic germline variants in MMR genes have not been investigated in large series of breast cancers. In this study, we screened the germline variants in MMR genes in 8085 consecutive Chinese breast cancer patients, and investigated the MMR/PD-L1 protein expression and tumor mutation burden (TMB) of breast tumors from MMR variant carriers. We found that 15 of 8085 patients (0.19%) carried a pathogenic germline variant in MMR genes. Compared with non-carriers, MMR variant carriers might have worse recurrence-free survival (unadjusted hazard ratios [HR] = 2.70, 95% CI: 1.12–6.49, P = 0.027) and distant recurrence-free survival (unadjusted HR = 3.24, 95% CI: 1.45–7.22, P = 0.004). More importantly, some of the breast cancers from MMR carriers displayed MMR protein loss (5/13), TMB-high (2/10), and PD-L1 positive expression (9/13). This study showed that MMR variant carriers were rare in breast cancer. They might have worse survival and part of them might benefit from immunotherapy.

Risk Analysis of Positive PD-L1 Expression and Clinicopathological Features and Survival Prognosis in Patients with Colorectal Cancer: Systematic Review and Meta-Analysis.

In order to explore the significance of PD-L1 expression in the prognosis and clinicopathological characteristics of colorectal cancer (CRC), the PubMed, Embase, Web of Science, Cochrane Library, CNKI, and multisquare databases are systematically searched for the relevant relationship between PD-L1 expression and CRC prognosis. The search time is completed until June 2021. Literature is filtered and data extracted by inclusion exclusion criteria, and Meta-analysis is performed with Stata SE12.0 software. 16 documents are included, and a total of 1997 CRC patients are included. The results show that recurrence-free survival (RFS) [OR = 2.69, 95%CI (2.07,3.48), P < 0.00001, I2 = 0%, Z = 7.50), and disease-free survival (DFS) (OR = 3.71, 95% CI (2.32,5.93), P < 0.00001, I2 = 37%, Z = 5.48) and PD-L1 expression and tumor differentiation (OR = 4.00, 95%CI (2.97,5.38), P < 0.00001, I2 = 0%, Z = 9.11) and lymphatic action metastasis (OR = 2.69,95% CI (2.07,3.48), P < 0.00001, I2 = 0%, Z = 7.50) is significantly associated.PD-L1 expression in tumor tissue suggests a poor prognosis in colorectal cancer, and the predictive significance of PD-L1 expression and PD-L1 expression in tumor cells in tumor-infiltrating immune cells may be inconsistent.

Expression comparison and clinical significance of PD-L1 (22C3) and PD-L1 (SP142) in triple negative breast cancer

Objective: To investigate the expression of programmed death ligand-1 (PD-L1, SP142) and PD-L1 (22C3) in triple-negative breast cancer (TNBC), and analyze their correlation with the clinicopathological factors and prognosis. Methods: The clinicopathologic data of 259 patients with TNBC treated in Cancer Hospital from August 2010 to December 2013 were collected. Whole section of surgical tissue samples were collected to conduct PD-L1 (SP142) and PD-L1 (22C3) immunohistochemical (IHC) staining. The PD-L1 expression in tumor cells and tumor infiltrating immune cells were visually assessed respectively, the relationship between PD-L1 expression and clinicopathologic characterizes were analyzed. Univariable and multivariable Cox proportional hazards regression models were used to test the correlations between PD-L1 expression and disease-free survival (DFS) and overall survival (OS). Results: The positive rates of SP142 (immune cell score, ICs≥1%) and 22C3 (combined positive score, CPS≥1) were 42.1%(109/259) and 41.3%(107/259) in TNBC tissues, respectively, with a total coincidence rate of 82.3%. The Kappa value of positive expression cases was 0.571 and the distribution difference of SP142 and 22C3 positive expression cases was statistically significant (P<0.001). The PD-L1 positive patients were less likely to have vascular invasion (P<0.05), but with higher histological grade and Ki-67 proliferation index (P<0.05). The recurrence/metastasis cases(8) of the patients with positive PD-L1 (SP142) was significantly lower than that of patients with negative PD-L1(SP142, 27, P=0.016). The positive expression of PD-L1 (SP142) patients were longer DFS (P=0.019). The OS of patients with positive PD-L1 (SP142) were longer than those with negative PD-L1 (SP142), but without significance (P=0.116). The positive expression of PD-L1 (22C3) was marginally associated with DFS and OS of patients (P>0.05). Conclusions: The expression of PD-L1 (22C3) is different from that of PD-L1 (SP142) in TNBC, and the two antibodies can't be interchangeable for each other in clinical tests. PD-L1 (SP142) status is an independent prognostic factor of DFS in TNBC. The DFS is significantly prolonged in patients with positive expression of PD-L1 (SP142).

Case Report: A PD-L1-Positive Patient With Pleomorphic Rhabdomyosarcoma Achieving an Impressive Response to Immunotherapy

There is currently a lack of effective systemic treatment for patients with advanced pleomorphic rhabdomyosarcoma (PRMS). Although programmed death protein 1 (PD-1) inhibitors have shown efficacy in various solid tumors, their effects on PRMS have not been well established. Here, we present a case of a 12-year-old Chinese male adolescent with metastatic PRMS who benefited from the PD-1 inhibitor nivolumab. The patient initially underwent primary tumor resection but failed to respond to subsequent first-line chemotherapy and second-line pazopanib treatment. Pathological examination showed positive PD-L1 expression and tumor-infiltrating lymphocytes in the tumor tissue, and the patient was administered nivolumab as a posterior-line treatment. After attaining a clinically partial response (PR), surgical resection was performed, which was followed by adjuvant nivolumab. At the time of the submission of this manuscript, the patient achieved recurrence-free survival (RFS) lasting 45 months and counting. This is the first clinical evidence that a patient with refractory PRMS was controlled by anti-PD-1 antibody, with an RFS lasting more than 3 years. This case suggests that PD-L1 expression and T-cell infiltration could be used as potential biomarkers for PRMS immunotherapy.

A multicenter, open-label, single-arm phase I trial of neoadjuvant nivolumab monotherapy for resectable gastric cancer

BackgroundNivolumab monotherapy has demonstrated superior efficacy in advanced unresectable gastric cancer (GC), but its impact on resectable GC remains unknown. This phase I study aimed to evaluate safety, feasibility, and potential biomarkers of neoadjuvant nivolumab monotherapy in resectable GC.MethodsUntreated, resectable, cT2 or more advanced gastric adenocarcinomas with clinical stage I, II, or III were treated with two doses of nivolumab before gastrectomy. Patients were excluded if their tumors may be applicable to neoadjuvant chemotherapy. The primary endpoint was the incidence of adverse event (AE) categories of special interest.ResultsAll of the 31 enrolled patients completed 2 doses of nivolumab monotherapy. While 30 (97%) patients underwent surgery with curative intent, 1 patient discontinued before the planned surgical intervention because of a newly emerging liver metastasis. Seven patients (23%) had nivolumab treatment-related AEs, and one patient had a treatment-related AE of grade 3–4. The incidences of treatment-related AE categories of special interest ranged from 0 to 6%. Notable surgical complications included two cases of grade 3 anastomotic leakage and two cases of pancreatic fistula. The major pathologic response (MPR) assessed by the independent pathology review committee was achieved in five (16%) patients, of which one patient had a pathologic complete response. The MPR was mostly observed in patients with positive PD-L1 expression, high microsatellite instability, and/or high tumor mutation burden.ConclusionsNeoadjuvant nivolumab monotherapy is feasible with an acceptable safety profile and induces a MPR in certain patients with resectable GC. (Registration: clinicaltrials.jp, JapicCTI-183895).