The effect of liver metastases on clinical efficacy of first-line programmed death-1 inhibitor plus chemotherapy in esophageal squamous cell carcinoma: A post hoc analysis of ASTRUM-007 and meta-analysis

OBJECTIVE

To explore the efficacy of serplulimab plus chemotherapy in esophageal squamous cell carcinoma (ESCC) patients with liver metastases.

METHODS

A post hoc exploratory analysis of ASTRUM-007 study was performed, focusing on the association between the liver metastases status and the clinical outcomes. A systematic literature search of electronic databases was conducted to identify eligible randomized controlled trials for the meta-analysis. Study-level pooled analyses of hazard ratios (HRs) for PFS according to liver metastases were performed.

RESULTS

The post hoc analysis of ASTRUM-007 showed that although patients with liver metastases had a worse prognosis comparing with the non-liver metastases patients in both treatment arms (serplulimab plus chemotherapy arm: median PFS, 5.7 vs. 6.6 months, HR 1.57 [95% CI, 1.15-2.13]; median OS, 13.7 vs. 15.3 months, HR 1.48 [95% CI, 1.09-1.98]; placebo plus chemotherapy arm: median PFS, 4.3 vs. 5.5 months, HR 1.58 [95% CI, 1.01-2.39]; median OS, 10.3 vs. 11.2 months, HR 1.32 [95% CI, 0.84-2.00]), OS and PFS benefits derived from serplulimab plus chemotherapy versus placebo plus chemotherapy in this study were observed in both patients with liver metastases (HR of PFS: 0.60; 95% CI, 0.37-0.97; HR of OS: 0.68; 95% CI, 0.43-1.11) and the non-liver metastases patients (HR of PFS: 0.62; 95% CI, 0.49-0.80; HR of OS: 0.69; 95% CI, 0.55-0.87) with similar magnitude. Three randomized controlled trials were included in the meta-analysis. Pooled HRs demonstrated that the addition of anti-PD-1 antibodies significantly improved PFS compared to chemotherapy alone regardless of liver metastases status.

CONCLUSIONS

This study reveals that the presence of liver metastases is a poor prognostic factor but does not affect the improvements in both PFS and OS brought by adding PD-1 blockade to chemotherapy in ESCC patients. Predictive biomarkers for survival in these patients warrant further investigation.

Hepatocytes coordinate immune evasion in cancer via release of serum amyloid A proteins

T cell infiltration into tumors is a favorable prognostic feature, but most solid tumors lack productive T cell responses. Mechanisms that coordinate T cell exclusion are incompletely understood. Here we identify hepatocyte activation via interleukin-6/STAT3 and secretion of serum amyloid A (SAA) proteins 1 and 2 as important regulators of T cell surveillance of extrahepatic tumors. Loss of STAT3 in hepatocytes or SAA remodeled the tumor microenvironment with infiltration by CD8+ T cells, while interleukin-6 overexpression in hepatocytes and SAA signaling via Toll-like receptor 2 reduced the number of intratumoral dendritic cells and, in doing so, inhibited T cell tumor infiltration. Genetic ablation of SAA enhanced survival after tumor resection in a T cell-dependent manner. Likewise, in individuals with pancreatic ductal adenocarcinoma, long-term survivors after surgery demonstrated lower serum SAA levels than short-term survivors. Taken together, these data define a fundamental link between liver and tumor immunobiology wherein hepatocytes govern productive T cell surveillance in cancer.

Metastatic site and clinical outcome of patients with deficient mismatch repair metastatic colorectal cancer treated with an immune checkpoint inhibitor in the first-line setting

PURPOSE

Only one-half of deficient mismatch repair (d-MMR) metastatic colorectal cancers (mCRC) demonstrate durable responses to immune checkpoint inhibitors (ICIs). Given preclinical data indicating that liver metastases sequester activated CD8+ T cells from systemic circulation, we examined clinical outcome by metastatic site.

PATIENTS AND METHODS

In a retrospective cohort of patients with d-MMR mCRCs treated at multiple centers in France (n = 66), we sought to validate data from a U.S. cohort, and performed pooled analysis (n = 104). All patients received first-line ICI monotherapy. Metastatic site was analyzed in relationship to tumor response (RECIST version 1.1), and with progression-free survival (PFS) by multivariable stratified Cox regression after adjustment for covariates.

RESULTS

Objective responses were achieved in 38/66 (58%) of patients in the validation cohort. Best tumor response included 13 (20%) complete responses (CR), 25 (38%) partial responses (PR), 16 (25%) stable disease, and 11 (17%) progressive disease (PD). One-year and 5-year PFS rates were 73% and 67%, respectively; 18 (27%) patients progressed during immunotherapy. Best tumor response was attenuated in patients with liver metastasis (P = 0.03). Presence of liver metastasis, but not other sites, was associated with significantly poorer PFS after adjustment for covariates (HRadj 2.82; 95%CI, 1.08-7.39; Padj=0.03). In a pooled analysis, liver metastasis remained significantly and independently associated with poorer PFS (HRadj 3.18; 95%CI, 1.52-6.67; Padj=0.002) and with attenuated tumor best response (P = 0.01).

CONCLUSIONS

Metastasis to the liver, but not other sites, was validated as an independent factor associated with poorer response and survival after ICI treatment in d-MMR mCRCs. These data underscore the need for novel therapeutic strategies in these patients.

Kupffer cells prevent pancreatic ductal adenocarcinoma metastasis to the liver in mice

Although macrophages contribute to cancer cell dissemination, immune evasion, and metastatic outgrowth, they have also been reported to coordinate tumor-specific immune responses. We therefore hypothesized that macrophage polarization could be modulated therapeutically to prevent metastasis. Here, we show that macrophages respond to β-glucan (odetiglucan) treatment by inhibiting liver metastasis. β-glucan activated liver-resident macrophages (Kupffer cells), suppressed cancer cell proliferation, and invoked productive T cell-mediated responses against liver metastasis in pancreatic cancer mouse models. Although excluded from metastatic lesions, Kupffer cells were critical for the anti-metastatic activity of β-glucan, which also required T cells. Furthermore, β-glucan drove T cell activation and macrophage re-polarization in liver metastases in mice and humans and sensitized metastatic lesions to anti-PD1 therapy. These findings demonstrate the significance of macrophage function in metastasis and identify Kupffer cells as a potential therapeutic target against pancreatic cancer metastasis to the liver.

Prognostic characteristics and clinical response to immunotherapy targeting programmed cell death 1 for patients with advanced gastric cancer with liver metastases

Background

The specific efficacy of immunotherapy for patients with liver metastases of gastric cancer is unclear. This study set out to explore the treatment response and related prognostic factors for patients with liver metastases of gastric cancer treated with immunotherapy.

Patients and methods

This retrospective cohort study included 135 patients with unresectable advanced gastric cancer. According to the presence of liver metastases and/or first-line treatment with immunotherapy, patients were divided into the following three groups: I-LM(-) group(patients without liver metastases treated with immunotherapy, n=66), I-LM(+) group(patients with liver metastases treated with immunotherapy, n=36), C-LM(+) group(patients with liver metastases treated with chemotherapy and/or target therapy, n=33). Cox regression analyses were used to identify factors associated with survival in all patients and the three groups, respectively.

Results

For the patients with liver metastases treated with immunotherapy, multivariate analysis showed that only the presence of peritoneal metastases was significantly associated with shorter PFS [hazard ratios (HR), 3.23; 95% CI, 1.12-9.32; P=0.030] and the patients with peritoneal metastases had shorter median PFS than patients without peritoneal metastases(3.1 vs 18.4 months; P=0.004), while the objective response rate was 100% in patients with HER2-positive (2 complete radiographic responses and 2 partial responses; 3 of 4 patients were still ongoing benefits [median follow-up time, 15.3 months ; interquartile range(IQR), 6.3-17.9 months]).

Conclusions

The findings suggest that patients with various types of gastric cancer liver metastases respond differently to immune checkpoint inhibitors, HER2-positive patients may derive clinical benefits from immune checkpoint inhibitors, while the presence of peritoneal metastases is associated with resistance.

Oligometastatic Disease in the Liver: The Role of Interventional Oncology

Oligometastatic disease represents a clinically discrete intermediate stage of cancer progression and is an expanding area of research. While surgical metastatectomy has been recognized for decades as an effective treatment option in select patients, options for metastasis-directed therapy have broadened in scope with advancements in the armamentarium of non- and minimally invasive modalities. Recent preclinical studies investigating the immunology surrounding liver metastases demonstrate treatment resistance to immunotherapy in affected patients and show how locoregional therapy has the ability to overcome this resistance. In this paper, we review advancements in our understanding of oligometastatic disease, metastasis-directed therapy, effect of liver metastasis on response to immunotherapy, and the burgeoning role of image-guided interventions in complementing cancer immunotherapy at the exciting crossroads of interventional oncology and immuno-oncology.

The Liver-Immunity Nexus and Cancer Immunotherapy

The impact of liver metastases on immune checkpoint-inhibitor effectiveness in patients with solid-tumor malignancies has been the focus of several recent clinical and translational studies. We review the literature describing the immune functions of the liver and particularly the mechanistic observations in these studies. The initial clinical observation was that pembrolizumab appeared to be much less effective in melanoma and non-small cell lung cancer (NSCLC) patients with liver metastasis. Subsequently other clinical studies have extended and reported similar findings with programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) inhibitors in many cancers. Two recent translational studies in animal models have dissected the mechanism of this systemic immune suppression. In both studies CD11b⁺ suppressive macrophages generated by liver metastasis in a two-site MC38 model appear to delete CD8⁺ T cells in a FasL-dependent manner. In addition, regulatory T-cell (Treg) activation was observed and contributed to the distal immunosuppression. Finally, we discuss some of the interventions reported to address liver immune suppression, such as radiation therapy, combination checkpoint blockade, and Treg depletion.

Lymphopenia in Cancer Patients and its Effects on Response to Immunotherapy: an opportunity for combination with Cytokines?

Quantitative lymphocyte alterations are frequent in patients with cancer, and strongly impact prognosis and survival. The development of cancers in immunosuppressed patients has demonstrated the contribution of different T cell populations, including CD4⁺ cells, in the control of cancer occurrence.Whereas absolute numbers of neutrophils, platelets and red blood cells are routinely monitored in clinic following treatments, because of possible short-term complications, absolute lymphocyte counts (ALC), their subpopulations or diversity (phenotype, TCR) are rarely analyzed and never used to choose therapy or as prognostic criteria. The recent identification of immune checkpoint inhibitors (ICPi) as powerful therapeutic agents has revitalized immunotherapy of cancer in a broader group of diseases than anticipated. The status of the immune system is now recognized as an important biomarker for response to these novel treatments. Blood ALC values, along with tumor infiltration by CD8⁺T cells, and ICPi and ICPi-ligand expression, are likely to be a potential marker of sensitivity to anti-ICPi therapy.In this article, we review the current knowledge on the incidence and significance of lymphopenia in cancer patients, and discuss therapeutic strategies to restore lymphocyte numbers.

Tissue-Specific Immunoregulation: A Call for Better Understanding of the "Immunostat" in the Context of Cancer

Checkpoint inhibitor therapy has been a breakthrough in cancer research, but only some patients with cancer derive substantial benefit. Although mechanisms underlying sensitivity and resistance to checkpoint inhibitors are being elucidated, the importance of organ-specific regulation of immunity is currently underappreciated. Here, we call for a greater understanding of tissue-specific immunoregulation, namely, "tissue-specific immunostats," to make advances in treatments for cancer. A better understanding of how individual organs at baseline regulate the immune system could enable an improved precision medicine approach to cancer immunotherapy. Cancer Discov; 8(4); 395-402. ©2018 AACR.

Population Modeling of Tumor Kinetics and Overall Survival to Identify Prognostic and Predictive Biomarkers of Efficacy for Durvalumab in Patients With Urothelial Carcinoma

Durvalumab is an anti‐PD‐L1 monoclonal antibody approved for patients with locally advanced or metastatic urothelial carcinoma (UC) that has progressed after platinum‐containing chemotherapy. A population tumor kinetic model, coupled with dropout and survival models, was developed to describe longitudinal tumor size data and predict overall survival in UC patients treated with durvalumab (NCT01693562) and to identify prognostic and predictive biomarkers of clinical outcomes. Model‐based covariate analysis identified liver metastasis as the most influential factor for tumor growth and immune‐cell PD‐L1 expression and baseline tumor burden as predictive factors for tumor killing. Tumor or immune‐cell PD‐L1 expression, liver metastasis, baseline hemoglobin, and albumin levels were identified as significant covariates for overall survival. These model simulations provided further insights into the impact of PD‐L1 cutoff values on treatment outcomes. The modeling framework can be a useful tool to guide patient selection and enrichment strategies for immunotherapies across various cancer indications.

Pembrolizumab use for the treatment of advanced melanoma

INTRODUCTION

Until recently, overall long term survival in patients with stage IV melanoma was lower than 10%. However, the treatment of melanoma has evolved rapidly over the last few years, with the advent of inhibitors of BRAF and MEK and of immunotherapeutic agents including ipilimumab, nivolumab, and pembrolizumab. Areas covered: This is a comprehensive review of the literature on the role of pembrolizumab in melanoma. Pembrolizumab is a Programmed Death Receptor 1 (PD-1) directed monoclonal antibody which is approved by FDA and EMA for the treatment of patients with metastatic melanoma. Expert opinion: Phase II and III trials demonstrated that pembrolizumab is superior to ipilimumab in previously untreated patients and to chemotherapy in ipilimumab pre-treated patients. Unfortunately, prospectively validated predictive markers are lacking. Immune-related adverse events are particularly interesting and should be managed per the published guidelines. There are still many issues that remain unresolved including: when to stop treatment, biomarkers for choosing a single agent or combination therapy, the optimal schedule of ipilimumab in combination with anti-PD1 monoclonal antibodies, optimal management of adverse events, the role of immunotherapy in specific populations, the optimal sequence of immunotherapy and the BRAF/MEK inhibitor combination in patients.

Pretreatment neutrophil-to-lymphocyte ratio as a marker of outcomes in nivolumab-treated patients with advanced non-small-cell lung cancer

OBJECTIVES

Efficient use of nivolumab in non-small-cell lung cancer (NSCLC) has been limited by the lack of a definitive predictive biomarker. In patients with metastatic melanoma treated with ipilimumab, a pretreatment neutrophil-to-lymphocyte ratio (NLR)<5 has been associated with improved survival. This retrospective cohort study aimed to determine whether the pretreatment NLR was associated with outcomes in NSCLC patients treated with nivolumab.

METHODS

We reviewed the medical records of all patients with previously treated advanced NSCLC who received nivolumab between March 2015 and March 2016 outside of a clinical trial at the University of Pennsylvania. Patients were dichotomized according to pretreatment NLR<5 vs. ≥5. Multivariable logistic regression and Cox proportional hazards models were used to assess the impact of pretreatment NLR on overall survival (OS), progression-free survival (PFS), and overall response rate (ORR).

RESULTS

175 patients were treated. Median age was 68 (range, 33-88); 54% were female. Twenty-five percent of patients had an Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥2; 46% had received ≥2 prior systemic therapies. In multivariate analyses, pretreatment neutrophil-to-lymphocyte ratio (NLR) ≥5 was independently associated with inferior OS (median 5.5 vs. 8.4 months; HR 2.07, 95% CI 1.3-3.3; p=0.002) and inferior PFS (median 1.9 vs. 2.8 months; HR 1.43, 95% CI 1.02-2.0; p=0.04).

CONCLUSIONS

In a cohort of patients with NSCLC treated with nivolumab in routine practice, pretreatment NLR≥5 was associated with inferior outcomes. It is unclear whether this marker is predictive or prognostic. Prospective studies are warranted to determine the utility of NLR in the context of other biomarkers of programmed death-1 (PD-1) therapy.

Immune-related response assessment during PD-1 inhibitor therapy in advanced non-small-cell lung cancer patients

Background

Tumor response characteristics using immune-related RECIST1.1 (irRECIST1.1) in advanced non-small-cell lung cancer (NSCLC) patients treated with nivolumab monotherapy in the clinical setting have not been previously described with a direct comparison with the assessments according to the conventional RECIST1.1.

Methods

Fifty-six advanced NSCLC patients treated with nivolumab monotherapy after its Food and Drug Administration (FDA) approval were retrospectively studied. Tumor burden was quantified on serial CT scans during therapy using irRECIST1.1, which uses unidimensional measurements and includes new lesion measurements in total tumor burden. Response assessments by irRECIST1.1 were compared with assessments by RECIST1.1. Responses of individual lesions in different organs were also compared.

Results

Tumor burden change at best overall response ranged from −66.8 to +278.1% (median: +3.9%). Response rate was 14% (8/56; 8 partial responses, 0 complete responses) by irRECIST1.1 and by RECIST1.1. Time-to-progression (TTP) by irRECIST1.1 was longer than TTP by RECIST1.1 (median TTP: not reached vs. 1.9 months, respectively). No patients experienced pseudoprogression during the study. Among 128 target lesions, the lesion-based size change at best response differed significantly across different organs, with adrenal lesions and lymph nodes having greater size decrease, followed by lung, while liver and other miscellaneous lesions had lesser degree of size decrease (p = 0.002).

Conclusions

Immune-related response evaluations using irRECIST1.1 in advanced NSCLC patients treated with nivolumab resulted in the identical response rate and longer TTP compared to RECIST1.1. No pseudoprogression cases were observed during the study. Adrenal lesions and lymph nodes were more responsive and liver lesions were less responsive to nivolumab.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-016-0193-2) contains supplementary material, which is available to authorized users.