Hyperprogressive disease: recognizing a novel pattern to improve patient management

Real-world effectiveness of nivolumab in advanced gastric cancer: the DELIVER trial (JACCRO GC-08)

BACKGROUND

There is no large real-world data regarding efficacy and safety of immunotherapy in gastric cancer (GC). Although some tumors can grow rapidly after immunotherapy, the patient proportions and survival outcomes are unclear in GC.

METHODS

A multicenter, prospective observational study was performed to evaluate clinical outcomes including survival time, safety, and tumor behavior of nivolumab treatment for patients with advanced GC. Primary endpoint was overall survival (OS), and secondary endpoints included response rate (RR), disease control rate (DCR), progression-free survival (PFS), tumor growth rate (TGR) at first evaluation, and safety.

RESULTS

Of 501 enrolled patients, 487 were evaluable (median age 70 years, 71% male, performance status 0/1/2 [42%/44%/14%], 21% HER2-pos, 42% patients with ascites). Median OS was 5.82 months (95% CI 5.29-7.00) with a 1-year survival rate of 30% and median PFS of 1.84 months (95% CI 1.71-1.97). The DCR was 39.4% and the RR was 14.2% (95% CI 10.3-18.8) in 282 patients with measurable lesions. In 219 patients evaluable for TGR, 20.5% were identified as hyperprogressive disease (HPD). OS from the first evaluation of patients with HPD was shorter compared with non-HPD (HR 1.77, 95% CI 1.25-2.51, P = 0.001), but it was not worse than that of patients with progression and non-HPD (HR 1.05, 95% CI 0.72-1.53, P = 0.8). A multivariate analysis revealed the presence of peritoneal metastasis was a prognostic factor for OS and PFS.

CONCLUSIONS

Our real-world data demonstrated the comparable survival time to a previous clinical trial and revealed the frequency and prognosis of patients with HPD in advanced GC treated with nivolumab.

Current Perspectives on the Immunosuppressive Niche and Role of Fibrosis in Hepatocellular Carcinoma and the Development of Antitumor Immunity

Immune checkpoint inhibitors have become the mainstay of treatment for hepatocellular carcinoma (HCC). However, they are ineffective in some cases. Previous studies have reported that genetic alterations in oncogenic pathways such as Wnt/β-catenin are the important triggers in HCC for primary refractoriness. T-cell exhaustion has been reported in various tumors and is likely to play a prominent role in the emergence of HCC due to chronic inflammation and cirrhosis-associated immune dysfunction. Immunosuppressive cells including regulatory T-cells and tumor-associated macrophages infiltrating the tumor are associated with hyperprogressive disease in the early stages of immune checkpoint inhibitor treatment. In addition, stellate cells and tumor-associated fibroblasts create an abundant desmoplastic environment by producing extracellular matrix. This strongly contributes to epithelial to mesenchymal transition via signaling activities including transforming growth factor beta, Wnt/β-catenin, and Hippo pathway. The abundant desmoplastic environment has been demonstrated in pancreatic ductal adenocarcinoma and cholangiocarcinoma to suppress cytotoxic T-cell infiltration, PD-L1 expression, and neoantigen expression, resulting in a highly immunosuppressive niche. It is possible that a similar immunosuppressive environment is created in HCC with advanced fibrosis in the background liver. Although sufficient understanding is required for the establishment of immune therapies of HCC, further investigations are still required in this field.

Immunotherapy, the promise for present and future of malignant pleural mesothelioma (MPM) treatment

Due to occupational asbestosis exposure, the incidence of malignant pleural mesothelioma (MPM) has continuously increased over the last 30 years, with a plateau anticipated around the year 2030 in Western countries. Molecular MPM carcinogenesis involves alterations of NF2, RASSF1, LATS2WT1, p16, as well as BAP-1tumor-suppressor genes, which usually regulate apoptosis, cell invasion, motility, cell division, chromatin remodeling, as well as control of DNA repair. In few selected patients, debulking surgery consisting of pleurectomy-decortication is carried out, resulting in unsatisfactory long-term results. For about 15 years, first-line chemotherapy has been primarily based on a doublet of pemetrexed and cisplatin. Adding the monoclonal antibody bevacizumab (Avastin®), which targets vascular endothelial growth factor (VEGF), has been shown to improve overall survival (OS) by nearly 19 months. The emergence of immune check-point inhibitors (ICIs) in MPM treatment has recently been associated with substantial survival improvements in both second- and first-line settings. Similarly to non-small-cell lung cancer (NSCLC) patients, on-going trials are presently exploring the chemotherapy-ICI combination in MPM management, and depending on their results, this combination could represent a further major advance in this previously orphan disease. The current article reviews recent clinical trial results, as well as future clinical developments in this moving field.

The combination of immune checkpoint inhibitors and chemotherapy in advanced non-small-cell lung cancer: the rational choice

Lung cancer is the second most common cancer worldwide and the leading cause of death among cancers. The progressive approvals of immunotherapy as first-line treatment options have helped improve cancer prognosis. However, longer follow-up has confirmed the possibility of acquired resistance to immune checkpoint inhibitors (ICIs) which can lead to late relapses. Chemotherapy can act as a priming therapy to increase a tumor's response to immunotherapy. We aim through this review to explain the mechanism behind ICI resistance and the value of chemotherapy in escaping this resistance. Finally, all US FDA approvals regarding the management of metastatic non-small-cell lung cancer using a combination of ICIs and chemotherapy are summarized.

Combination immunotherapy with nivolumab and ipilimumab in patients with rare gynecological malignancies: results of the CA209-538 clinical trial

BACKGROUND

Patients with rare cancers represent 55% of all gynecological malignancies and have poor survival outcomes due to limited treatment options. Combination immunotherapy with the anti-programmed cell death protein 1 (anti-PD-1) antibody nivolumab and the anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) antibody ipilimumab has demonstrated significant clinical efficacy across a range of common malignancies, justifying evaluation of this combination in rare gynecological cancers.

METHODS

This multicenter phase II study enrolled 43 patients with advanced rare gynecological cancers. Patients received induction treatment with nivolumab and ipilimumab at a dose of 3 mg/kg and 1 mg/kg, respectively, every 3 weeks for four doses. Treatment was continued with nivolumab monotherapy at 3 mg/kg every 2 weeks until disease progression or a maximum of 2 years. The primary endpoint was the proportion of patients with disease control at week 12 (complete response, partial response or stable disease (SD) by Response Evaluation Criteria In Solid Tumor V.1.1). Exploratory evaluations correlated clinical outcomes with tumor programmed death-ligand 1 (PD-L1) expression and tumor mutational burden (TMB).

RESULTS

The objective response rate in the radiologically evaluable population was 36% (12/33 patients) and in the intention-to-treat population was 28% (12/43 patients), with additional 7 patients obtaining SD leading to a disease control rate of 58% and 44%, respectively. Durable responses were seen across a range of tumor histologies. Thirty-one (72%) patients experienced an immune-related adverse event (irAE) with a grade 3/4 irAE observed in seven (16%) patients. Response rate was higher among those patients with baseline PD-L1 expression (≥1% on tumor cells) but was independent of TMB.

CONCLUSIONS

Ipilimumab and nivolumab combination treatment has significant clinical activity with a favorable safety profile across a range of advanced rare gynecological malignancies and warrants further investigation in these tumor types.

Upfront progression under pembrolizumab followed by a complete response after encorafenib and cetuximab treatment in BRAF V600E-mutated and microsatellite unstable metastatic colorectal cancer patient: A case report

Two new treatments have recently become standard care for patients with metastatic colorectal cancer (mCRC): encorafenib (BRAF inhibitor) associated with cetuximab (anti-EGFR) in the second or third line of chemotherapy for BRAF V600E tumors, and pembrolizumab (an anti PD-1 immune checkpoint inhibitor) for tumors harboring microsatellite instability (MSI)-high and/or deficient mismatch repair (dMMR). Furthermore, 30% of BRAF V600E mutated mCRC are MSI/dMMR through a sporadic hypermethylation of the promoter of hMLH1. We report here, for the first time, the case of a patient with BRAF V600E, PIK3CA, and SMAD4 mutated and dMMR/MSI mCRC, in whom we observed an atypical response pattern under the sequence of pembrolizumab followed by the doublet encorafenib and cetuximab treatment. The patient was progressive after a single cycle of pembrolizumab followed by a rapid complete response after only 2 months of treatment with encorafenib and cetuximab, discovered during R0 cytoreduction surgery for peritoneal carcinomatosis.

CT-Based Peritumoral and Intratumoral Radiomics as Pretreatment Predictors of Atypical Responses to Immune Checkpoint Inhibitor Across Tumor Types: A Preliminary Multicenter Study

OBJECTIVE

To develop and validate a new strategy based on radiomics features extracted from intra- and peritumoral regions on CT images for the prediction of atypical responses to the immune checkpoint inhibitor (ICI) in cancer patients.

METHODS

In total, 135 patients derived from five hospitals with pathologically confirmed malignancies receiving ICI were included in this retrospective study. Atypical responses including pseudoprogression (PsP) and hyperprogression disease (HPD) were identified as their definitions. A subgroup of standard progression disease (sPD) in 2018 was also involved in this study. Based on pretreatment CT imaging, a total of 107 features were extracted from intra- and peri-tumoral regions, respectively. The least absolute shrinkage and selection operator (Lasso) algorithm was used for feature selection, and multivariate logistic analysis was used to develop radiomics signature (RS). Finally, a total of nine RSs, derived from intra-tumoral, peri-tumoral, and combination of both regions, were built respectively to distinguish PsP vs. HPD, PsP vs. sPD, and HPD vs. sPD. The performance of the RSs was evaluated with discrimination, calibration, and clinical usefulness.

RESULTS

No significant difference was found when compared in terms of clinical characteristics of PsP, HPD, and sPD. RS based on combined regions outperformed those from either intra-tumoral or peri-tumoral alone, yielding an AUC (accuracy) of 0.834 (0.827) for PsP vs. HPD, 0.923 (0.868) for PsP vs. sPD, and 0.959 (0.894) for HPD vs. sPD in the training datasets, and 0.835 (0.794) for PsP vs. HPD, 0.919 (0.867) for PsP vs. sPD, and 0.933 (0.842) for HPD vs. sPD in the testing datasets. The combined RS showed good fitness (Hosmer-Lemeshow test p > 0.05) and provided more net benefit than the treat-none or treat-all scheme by decision curve analysis in both training and testing datasets.

CONCLUSION

Pretreatment radiomics are helpful to predict atypical responses to ICI across tumor types. The combined RS outperformed those from either intra- or peri-tumoral alone which may provide a more comprehensive characterization of atypical responses to ICI.

PI3Kγδ inhibitor plus radiation enhances the antitumour immune effect of PD-1 blockade in syngenic murine breast cancer and humanised patient-derived xenograft model

INTRODUCTION

We hypothesised that the combined use of radiation therapy and a phosphoinositide 3-kinaseγδ inhibitor to reduce immune suppression would enhance the efficacy of an immune checkpoint inhibitor.

METHODS

Murine breast cancer cells (4T1) were grown in both immune-competent and -deficient BALB/c mice, and tumours were irradiated by 3 fractions of 24 Gy. A PD-1 blockade and a phosphoinositide 3-kinase (PI3K)γδ inhibitor were then administered every other day for 2 weeks. The same experiments were performed in humanised patient-derived breast cancer xenograft model and its tumour was sequenced to identify immune-related pathways and profile infiltrated immune cells. Transcriptomic and clinical data were acquired from The Cancer Genome Atlas pan-cancer cohort, and the deconvolution algorithm was used to profile immune cell repertoire.

RESULTS

Using a PI3Kγδ inhibitor, radiation therapy (RT) and PD-1 blockade significantly delayed primary tumour growth, boosted the abscopal effect and improved animal survival. RT significantly increased CD8+cytotoxic T-cell fractions, immune-suppressive regulatory T cells (T_regs), myeloid-derived suppressor cells and M2 tumour-associated macrophages (TAMs). However, the PI3Kγδ inhibitor significantly lowered the proportions of T_regs, myeloid-derived suppressor cells and M2 TAMs, achieving dramatic gains in splenic, nodal, and tumour CD8+ T-cell populations after triple combination therapy. In a humanised patient-derived breast cancer xenograft model, triple combination therapy significantly delayed tumour growth and decreased immune-suppressive pathways. In The Cancer Genome Atlas cohort, high T_reg/CD8+ T cell and M2/M1 TAM ratios were associated with poor overall patient survival.

CONCLUSION

These findings indicate PI3Kγ and PI3Kδ are clinically relevant targets in an immunosuppressive TME, and combining PI3Kγδ inhibitor, RT and PD-1 blockade may overcome the therapeutic resistance of immunologically cold tumours.

SYNOPSIS

Combining PI3Kγδ inhibitor, RT, and PD-1 blockade may be a viable clinical approach, helping to overcome the therapeutic resistance of immunologically cold tumours such as breast cancer.

Resistance to immune checkpoint inhibitors in advanced gastro-oesophageal cancers

Immune checkpoint inhibitors (ICIs) have altered the treatment paradigm across a range of tumour types, including gastro-oesophageal cancers. For patients with any cancer type who respond, ICIs can confer long-term disease control and significantly improve survival and quality of life, but for patients with gastro-oesophageal cancer, ICIs can be transformative, as durable responses in advanced disease have hitherto been rare, especially in those patients who are resistant to first-line cytotoxic therapies. Results from trials in patients with advanced-stage gastro-oesophageal cancer have raised hopes that ICIs will be successful as adjuvant and neoadjuvant treatments in early-stage disease, when the majority of patients relapse after potential curative treatments, and several trials are ongoing. Unfortunately, however, ICI-responding patients appear to constitute a minority subgroup within gastro-oesophageal cancer, and resistance to ICI therapy (whether primary or acquired) is common. Understanding the biological mechanisms of ICI resistance is a current major research challenge and involves investigation of both tumour and patient-specific factors. In this review, we discuss the mechanisms underlying ICI resistance and their potential specific applications of this knowledge towards precision medicine strategies in the management of gastro-oesophageal cancers in clinical practice.

Mining the Gut Microbiota for Microbial-Based Therapeutic Strategies in Cancer Immunotherapy

The past two decades witnessed a revolution in our understanding of host–microbiota interactions that led to the concept of the super-organism consisting of a eukaryotic part and a prokaryotic part. Owing to the critical role of gut microbiota in modulating the host immune system, it is not beyond all expectations that more and more evidence indicated that the shift of gut microbiota influenced responses to numerous forms of cancer immunotherapy. Therapy targeting gut microbiota is becoming a promising strategy to improve cancer immunotherapy. In this review, we discuss the role of the gut microbiota in response to cancer immunotherapy, the mechanisms that the gut microbiota influences cancer immunotherapy, and therapeutic strategies targeting gut microbiota to improve cancer immunotherapy.

Comparison of Different Methods for Defining Hyperprogressive Disease in NSCLC

Introduction

Hyperprogressive disease (HPD) as a consequence of immune checkpoint inhibitors in NSCLC has been reported in multiple studies. However, inconsistent results in incidence and survival outcomes within studies, together with different assessment methods, have led to increasing controversy regarding the concept of HPD.

Methods

Consecutive patients treated with nivolumab (N = 42) or docetaxel (N = 37) were evaluated. HPD was quantified by applying three different methods (tumor growth rate [TGR], tumor growth kinetics [TGK], and Response Evaluation Criteria in Solid Tumors version 1.1 [RECIST 1.1]). HPD rates were compared between and within both cohorts using the different methods.

Results

Using TGR, TGK, and RECIST 1.1, we identified seven (16.7%), seven (16.7%), and six (14.3%) patients with HPD in the nivolumab cohort and three (8.1%), four (10.8%), and five (13.6%) in the docetaxel cohort, respectively. We observed a higher concordance between TGR and TGK (90.1%) compared with RECIST 1.1 (31.3% and 37.5% with TGR and TGK, respectively). We found no significant differences in the overall survival between patients with progressive disease and HPD in either cohort.

Conclusions

TGR and TGK revealed high concordance rates for identifying patients with HPD in NSCLC. The incidence of HPD was numerically higher in patients treated with immune checkpoint inhibitors. Standardization of methods for measuring HPD and its exploration in larger studies are needed to establish its clinical meaning in NSCLC.

Identification of CCNB2 as A Potential Non-Invasive Breast Cancer Biomarker in Peripheral Blood Mononuclear Cells Using The Systems Biology Approach

OBJECTIVE

Breast cancer (BC) still remains an imperative clinical issue, despite advances in the diagnosis, prognosis and treatment modalities of this malignancy. Hence, progress has been made to identify non-invasive, high sensitive and specific biomarkers. Since immune system affects development of breast cancer, peripheral blood mononuclear cells (PBMCs) -a subpopulation of immune cells- can be considered as a promising tool in the field of BC biomarker research. In the current study, we initially attempted to use concept of the present shared biomarkers in solid tumors and systemic immune profile and then evaluate correlation of these biomarkers to clinical use in cancer research.

MATERIALS AND METHODS

In this experimental study, available microarray gene expression datasets of BC as well as the related PBMCs were retrieved and downloaded from the Gene Expression Omnibus (GEO) database, followed by analysis using GEO2R along with affylmGUI, a R-based package, to obtain differentially expressed genes (DEGs). Signature genes from 20 types of cancer were also applied to validate DEGs. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was carried out to assess mRNA level of CCNB2 in PBMC of the BC patients and healthy subjects.

RESULTS

DEGs analysis for the transcription profile of BC cells and PBMCs showed two shared targets, CCNB2 and PGK1. Validation with systems biology using reweighted 20 types of cancer signature genes revealed that CCNB2 is the only common target in BC and its related PBMCs, which was further validated by qRT-PCR implying a significant increase in the level of CCNB2 in the BC patients.

CONCLUSION

Results of this study demonstrated that PBMCs are affected by BC cells and CCNB2 may be of value as a diagnostic biomarker for breast cancer. However, verification would require future detailed experimental plans.

The Combiome Hypothesis: Selecting Optimal Treatment for Cancer Patients

Existing approaches for cancer diagnosis are inefficient in the use of diagnostic tissue, and decision-making is often sequential, typically resulting in delayed treatment initiation. Future diagnostic testing needs to be faster and optimize increasingly complex treatment decisions. We envision a future where comprehensive testing is routine. Our approach, termed the "combiome," combines holistic information from the tumor, and the patient's immune system. The combiome model proposed here advocates synchronized up-front testing with a panel of sensitive assays, revealing a more complete understanding of the patient phenotype and improved targeting and sequencing of treatments. Development and eventual adoption of the combiome model for diagnostic testing may provide better outcomes for all cancer patients, but will require significant changes in workflows, technology, regulations, and administration. In this review, we discuss the current and future testing landscape, targeting of personalized treatments, and technological and regulatory advances necessary to achieve the combiome.

Overcoming microenvironmental resistance to PD-1 blockade in genetically engineered lung cancer models

Immune checkpoint blockade (ICB) with PD-1 or PD-L1 antibodies has been approved for the treatment of non-small cell lung cancer (NSCLC). However, only a minority of patients respond, and sustained remissions are rare. Both chemotherapy and antiangiogenic drugs may improve the efficacy of ICB in mouse tumor models and patients with cancer. Here, we used genetically engineered mouse models of Kras ^G12D/+;p53 ^-/- NSCLC, including a mismatch repair-deficient variant (Kras ^G12D/+;p53 ^-/-;Msh2 ^-/-) with higher mutational burden, and longitudinal imaging to study tumor response and resistance to combinations of ICB, antiangiogenic therapy, and chemotherapy. Antiangiogenic blockade of vascular endothelial growth factor A and angiopoietin-2 markedly slowed progression of autochthonous lung tumors, but contrary to findings in other cancer types, addition of a PD-1 or PD-L1 antibody was not beneficial and even accelerated progression of a fraction of the tumors. We found that antiangiogenic treatment facilitated tumor infiltration by PD-1⁺ regulatory T cells (T_regs), which were more efficiently targeted by the PD-1 antibody than CD8⁺ T cells. Both tumor-associated macrophages (TAMs) of monocyte origin, which are colony-stimulating factor 1 receptor (CSF1R) dependent, and TAMs of alveolar origin, which are sensitive to cisplatin, contributed to establish a transforming growth factor-β-rich tumor microenvironment that supported PD-1⁺ T_regs Dual TAM targeting with a combination of a CSF1R inhibitor and cisplatin abated T_regs, redirected the PD-1 antibody to CD8⁺ T cells, and improved the efficacy of antiangiogenic immunotherapy, achieving regression of most tumors.

Lung Cancer Surgery after Neoadjuvant Immunotherapy

In early-stage lung cancer, recurrences are observed even after curative resection. Neoadjuvant immunotherapy might be a promising approach to eliminate micrometastasis and to potentially reduce recurrence rates and improve survival. Early trials have shown encouraging rates of pathologic response to neoadjuvant therapy and have demonstrated that surgery can be safely performed after neoadjuvant immunotherapy with various agents and in combination with chemo-(radio)therapy. However, whether these response rates translate into improved disease-free survival rates and overall survival rates remains to be determined by ongoing phase III studies.

Hyperprogressive disease in patients with advanced renal cell carcinoma: a new pattern of post-treatment cancer behavior

Renal cell carcinoma (RCC) is among the most common cancers of the genitourinary system. Once RCC has progressed to a high tumor stage, surgery is no longer the optimal option, and treatment with drugs is more suitable. However, a proportion of patients with advanced RCC (aRCC) experience accelerated progression following targeted therapy or immunotherapy, a condition known as hyperprogressive disease (HPD). There is a growing body of literature that recognizes the importance of HPD. In the present review, thousands of studies that describe a variety of treatments for aRCC were identified in PubMed, Web of Science, and Cochrane Library and analyzed to establish the severity of clinical outcomes. Therefore, we managed to perform a review related to HPD of aRCC in these databases. It was found that 7~74% of patients advanced into progressive disease, 0~45% of patients died during post-treatment assessment, possibly due to fatal HPD. However, risk factors, mechanisms, and predictive factors are still not entirely clear. It is suggested that combination therapies might play a pivotal role in preventing HPD. Additional light needs to be shed on customization of therapies for aRCC after more data is collected and analyzed for HPD.

Leveraging NKG2D Ligands in Immuno-Oncology

Immune checkpoint inhibitors (ICI) revolutionized the field of immuno-oncology and opened new avenues towards the development of novel assets to achieve durable immune control of cancer. Yet, the presence of tumor immune evasion mechanisms represents a challenge for the development of efficient treatment options. Therefore, combination therapies are taking the center of the stage in immuno-oncology. Such combination therapies should boost anti-tumor immune responses and/or target tumor immune escape mechanisms, especially those created by major players in the tumor microenvironment (TME) such as tumor-associated macrophages (TAM). Natural killer (NK) cells were recently positioned at the forefront of many immunotherapy strategies, and several new approaches are being designed to fully exploit NK cell antitumor potential. One of the most relevant NK cell-activating receptors is NKG2D, a receptor that recognizes 8 different NKG2D ligands (NKG2DL), including MICA and MICB. MICA and MICB are poorly expressed on normal cells but become upregulated on the surface of damaged, transformed or infected cells as a result of post-transcriptional or post-translational mechanisms and intracellular pathways. Their engagement of NKG2D triggers NK cell effector functions. Also, MICA/B are polymorphic and such polymorphism affects functional responses through regulation of their cell-surface expression, intracellular trafficking, shedding of soluble immunosuppressive isoforms, or the affinity of NKG2D interaction. Although immunotherapeutic approaches that target the NKG2D-NKG2DL axis are under investigation, several tumor immune escape mechanisms account for reduced cell surface expression of NKG2DL and contribute to tumor immune escape. Also, NKG2DL polymorphism determines functional NKG2D-dependent responses, thus representing an additional challenge for leveraging NKG2DL in immuno-oncology. In this review, we discuss strategies to boost MICA/B expression and/or inhibit their shedding and propose that combination strategies that target MICA/B with antibodies and strategies aimed at promoting their upregulation on tumor cells or at reprograming TAM into pro-inflammatory macrophages and remodeling of the TME, emerge as frontrunners in immuno-oncology because they may unleash the antitumor effector functions of NK cells and cytotoxic CD8 T cells (CTL). Pursuing several of these pipelines might lead to innovative modalities of immunotherapy for the treatment of a wide range of cancer patients.

Cancer Immunotherapies: From Efficacy to Resistance Mechanisms - Not Only Checkpoint Matters

The immunotherapeutic treatment of various cancers with an increasing number of immune checkpoint inhibitors (ICIs) has profoundly improved the clinical management of advanced diseases. However, just a fraction of patients clinically responds to and benefits from the mentioned therapies; a large proportion of patients do not respond or quickly become resistant, and hyper- and pseudoprogression occur in certain patient populations. Furthermore, no effective predictive factors have been clearly screened or defined. In this review, we discuss factors underlying the elucidation of potential immunotherapeutic resistance mechanisms and the identification of predictive factors for immunotherapeutic responses. Considering the heterogeneity of tumours and the complex immune microenvironment (composition of various immune cell subtypes, disease processes, and lines of treatment), checkpoint expression levels may not be the only factors underlying immunotherapy difficulty and resistance. Researchers should consider the tumour microenvironment (TME) landscape in greater depth from the aspect of not only immune cells but also the tumour histology, molecular subtype, clonal heterogeneity and evolution as well as micro-changes in the fine structural features of the tumour area, such as myeloid cell polarization, fibroblast clusters and tertiary lymphoid structure formation. A comprehensive analysis of the immune and molecular profiles of tumour lesions is needed to determine the potential predictive value of the immune landscape on immunotherapeutic responses, and precision medicine has become more important.

Circulating regulatory T cells predict efficacy and atypical responses in lung cancer patients treated with PD-1/PD-L1 inhibitors

Background

Immune checkpoint inhibitors (ICIs) have become the standard of care for a variety of cancers, including non-small cell lung cancer (NSCLC). In this study, we investigated the frequency of pseudoprogression and hyperprogression in lung cancer patients treated with ICIs in the real world and aimed to discover a novel candidate marker to distinguish pseudoprogression from hyperprogression soon after ICI treatment.

Methods

This study included 74 patients with advanced NSCLC who were treated with PD-1/PD-L1 inhibitors at Chungnam National University Hospital (CNUH) between January 2018 and August 2020. Chest X-rays were examined on day 7 after the first ICI dose to identify changes in the primary mass, and the response was assessed by computed tomography (CT). We evaluated circulating regulatory T (Treg) cells using flow cytometry and correlated the findings with clinical outcomes.

Results

The incidence of pseudoprogression was 13.5%, and that of hyperprogression was 8.1%. On day 7 after initiation of treatment, the frequency of CD4⁺CD25⁺CD127^loFoxP3⁺ Treg cells was significantly decreased compared with baseline (P = 0.038) in patients who experienced pseudoprogression and significantly increased compared with baseline (P = 0.024) in patients who experienced hyperprogression. In the responder group, the frequencies of CD4⁺CD25⁺CD127^loFoxP3⁺ Treg cells and PD-1⁺CD4⁺CD25⁺CD127^loFoxP3⁺ Treg cells were significantly decreased 7 days after commencement of treatment compared with baseline (P = 0.034 and P < 0.001, respectively).

Conclusion

Circulating Treg cells represent a promising potential dynamic biomarker to predict efficacy and differentiate atypical responses, including pseudoprogression and hyperprogression, after immunotherapy in patients with NSCLC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00262-021-03018-y.

Hyperprogressive Disease in Cancers Treated With Immune Checkpoint Inhibitors

Immunotherapy, which takes advantage of the immune system to eliminate cancer cells, has been widely studied and applied in oncology. Immune checkpoint inhibitors (ICIs) prevent the immune system from being turned off before cancer cells are eliminated. They have proven to be among the most promising and effective immunotherapies, with significant survival benefits and durable responses in diverse tumor types. However, an increasing number of retrospective studies have found that some patients treated with ICIs experience unusual responses, including accelerated proliferation of tumor cells and rapid progression of the disease, with poor outcomes. Such unexpected adverse events are termed hyperprogressive disease (HPD), and their occurrence suggests that ICIs are detrimental to a subset of cancer patients. HPD is common, with an incidence ranging between 4 and 29% in several cancer types. However, the mechanisms of HPD remain poorly understood, and no clinical predictive factors of HPD have been identified. In this review, we summarize current findings, including retrospective studies and case reports, and focus on several key issues including the defining characteristics, predictive biomarkers, potential mechanisms of HPD, and strategies for avoiding HPD after ICI treatment.

A Phase 2 Study of Camrelizumab for Advanced Hepatocellular Carcinoma: Two-Year Outcomes and Continued Treatment beyond First RECIST-Defined Progression

INTRODUCTION

In a multicenter, open-label, parallel-group, randomized, phase 2 study for pretreated advanced hepatocellular carcinoma (HCC), camrelizumab showed potent antitumor activity and acceptable safety profile. The aim of this report was to provide long-term data and evaluate potential benefit of treatment with camrelizumab beyond progression.

METHODS

From November 15, 2016, to November 16, 2017, 217 patients received camrelizumab 3 mg/kg intravenously every 2 or 3 weeks. Treatment beyond first Response Evaluation Criteria in Solid Tumors (RECIST)-defined progression (TBP) with camrelizumab was allowed.

RESULTS

At data cutoff of December 16, 2019 (>2 years after the last patient enrollment; median duration of follow-up, 13.2 months [IQR 5.7-25.8]), 14 (43.8%) of the 32 responses per blinded independent central review were ongoing. The median duration of response was not reached (range 2.5-30.5 + months). The ongoing response rates at 12, 18, and 24 months were 68.3% (95% confidence interval [CI] 47.7-82.2), 59.8% (95% CI 38.8-75.6), and 53.1% (95% CI 31.0-71.0), respectively. The median overall survival (OS) was 14.2 months (95% CI 11.5-16.3). The 18- and 24-month OS rates were 41.3% (95% CI 34.6-47.9) and 33.7% (95% CI 27.3-40.2), respectively. Of the 172 patients who experienced RECIST-defined progression per investigator, 102 received TBP, while 70 did not (non-TBP). The median OS was 16.9 months (95% CI 13.3-22.6) in the TBP group versus 9.4 months (95% CI 5.8-14.8) in the non-TBP group, and the 18- and 24-month OS rates were 47.5% (95% CI 37.3-56.9) versus 33.1% (95% CI 22.3-44.3) and 38.8% (95% CI 29.2-48.4) versus 23.2% (95% CI 13.8-34.1), respectively. No new safety signals of camrelizumab were observed.

CONCLUSIONS

With prolonged follow-up, camrelizumab continues to demonstrate the durable response and long survival in pretreated advanced HCC patients with manageable toxicities, especially in those who continued the treatment beyond first RECIST-defined progression.

Selecting the optimal immunotherapy regimen in driver-negative metastatic NSCLC

The treatment landscape of driver-negative non-small-cell lung cancer (NSCLC) is rapidly evolving. Immune-checkpoint inhibitors, specifically those targeting PD-1 or PD-L1, have demonstrated durable efficacy in a subset of patients with NSCLC, and these agents have become the cornerstone of first-line therapy. Approved immunotherapeutic strategies for treatment-naive patients now include monotherapy, immunotherapy-exclusive regimens or chemotherapy-immunotherapy combinations. Decision making in this space is complex given the absence of head-to-head prospective comparisons, although a thorough analysis of long-term efficacy and safety data from pivotal clinical trials can provide insight into the optimal management of each subset of patients. Indeed, histological subtype and the extent of tumour cell PD-L1 expression are paramount to regimen selection, although other clinicopathological factors and patient preferences might also be relevant in certain scenarios. Finally, several emerging biomarkers and novel therapeutic strategies are currently under investigation, and these might further refine the current treatment paradigm. In this Review, we discuss the current treatment landscape and detail our approach to first-line immunotherapy regimen selection for patients with advanced-stage, driver-negative NSCLC.

Advancing to the era of cancer immunotherapy

Cancer greatly affects the quality of life of humans worldwide and the number of patients suffering from it is continuously increasing. Over the last century, numerous treatments have been developed to improve the survival of cancer patients but substantial progress still needs to be made before cancer can be truly cured. In recent years, antitumor immunity has become the most debated topic in cancer research and the booming development of immunotherapy has led to a new epoch in cancer therapy. In this review, we describe the relationships between tumors and the immune system, and the rise of immunotherapy. Then, we summarize the characteristics of tumor‐associated immunity and immunotherapeutic strategies with various molecular mechanisms by showing the typical immune molecules whose antibodies are broadly used in the clinic and those that are still under investigation. We also discuss important elements from individual cells to the whole human body, including cellular mutations and modulation, metabolic reprogramming, the microbiome, and the immune contexture. In addition, we also present new observations and technical advancements of both diagnostic and therapeutic methods aimed at cancer immunotherapy. Lastly, we discuss the controversies and challenges that negatively impact patient outcomes.

Hyperprogressive Disease Caused by PD-1 Inhibitors for the Treatment of Pan-Cancer

Background

Nowadays, PD-1/PD-L1 inhibitors are widely used to treat various malignant tumors. However, during the immunotherapy in a few patients, a flare-up of tumor growth occurred. This new pattern of progression is called hyperprogressive disease (HPD). Patients and Methods. The retrospective study included 377 patients with various malignant tumors treated with PD-1 inhibitors (nivolumab or pembrolizumab) in the Chinese PLA General Hospital from January 2015 to January 2019. Clinicopathologic variables, tumor growth rate (TGR), and treatment outcomes were analyzed in patients with pan-cancer treated with PD-1 inhibitors. HPD was defined as the difference of TGR before and during immunotherapy exceeding 50%.

Results

In 38 of 377 patients (10.08%), HPD occurred after treatment with PD-1 inhibitors. Patients with HPD had lower overall survival (OS) than those without HPD (median OS, 3.6months (95% CI, 3.0-4.2) vs. 7.3 months (95% CI, 5.9-8.7); P < 0.01). Factors related to HPD include more than 2 metastatic sites, ECOG performance status ≥ 2, hepatic metastases, and lactate dehydrogenase level greater than normal upper limit. KRAS status was significantly associated with HPD in patients with colorectal cancer. In the exploratory predictors' analysis, the rapid increase of characteristic tumor markers (such as CEA in colorectal cancer, CA199 in pancreatic cancer and cholangiocarcinoma) within one month was found to be associated with the occurrence of HPD.

Conclusions

HPD was developed with different rates in a variety of malignant tumor patients treated with PD-1 inhibitors and related to some clinicopathological features and poor prognosis. Tumor markers, especially CA199, might be served as early predictors of HPD.

Differences in treatment effect size between progression-free survival and overall survival in anti-PD-1/PD-L1 inhibitors-based trials in advanced NSCLC: a systematic review and meta-analysis

Background

To investigate the differences in treatment effect sizes between progression-free survival (PFS) and overall survival (OS) in advanced non-small cell lung cancer (NSCLC) treated with programmed cell death 1 (PD-1) and its ligand (PD-L1) blockade-based treatments.

Methods

The differences in treatment effect sizes between PFS and OS were assessed by using a ratio of hazard ratio (rHR): the HR for PFS to that for OS. A random effects meta-analysis across trials was conducted to generate the combined rHR. We also evaluated the feasibility of adopting PFS as the surrogate of OS by using Spearman correlation coefficient (R) between logHR_PFS and logHR_OS.

Results

A total of 27 randomized controlled trials (RCTs) with 15,590 patients were included. Treatment effect sizes were comparable, on average, for OS than for PFS (pooled rHR, 0.98; 95% CI, 0.91 to 1.08). Subgroup analysis revealed that treatment effect sizes were greater for OS than for PFS for trials with immunotherapy as second or above line treatment (rHR, 1.17; 95% CI, 1.06 to 1.29), while the differences were greater for PFS than for OS for trials with immunotherapy as first-line setting (rHR, 0.91; 95% CI, 0.84 to 0.99; P_interaction<0.01). The coefficient of determination was 40% and R was 0.63 between logHR_PFS and logHR_OS. Subgroup analysis showed that coefficient of determination and R were 62% and 0.79 in trials with immunotherapy as first-line setting, 22% and 0.47 in trials with immunotherapy as second or above line treatment, respectively.

Discussion

Treatment effect sizes between PFS and OS were roughly consistent in trials with different anti-PD-(L)1 inhibitor-based therapies. PFS could be a potential alternative endpoint for OS in trials with immunotherapy as first-line setting, but PFS should be cautiously interpreted without OS data for trials with immunotherapy as second or above line treatment.

TGF-β inhibition can overcome cancer primary resistance to PD-1 blockade: A mathematical model

Immune checkpoint inhibitors have demonstrated, over the recent years, impressive clinical response in cancer patients, but some patients do not respond at all to checkpoint blockade, exhibiting primary resistance. Primary resistance to PD-1 blockade is reported to occur under conditions of immunosuppressive tumor environment, a condition caused by myeloid derived suppressor cells (MDSCs), and by T cells exclusion, due to increased level of T regulatory cells (Tregs). Since TGF-β activates Tregs, TGF-β inhibitor may overcome primary resistance to anti-PD-1. Indeed, recent mice experiments show that combining anti-PD-1 with anti-TGF-β yields significant therapeutic improvements compared to anti-TGF-β alone. The present paper introduces two cancer-specific parameters and, correspondingly, develops a mathematical model which explains how primary resistance to PD-1 blockade occurs, in terms of the two cancer-specific parameters, and how, in combination with anti-TGF-β, anti-PD-1 provides significant benefits. The model is represented by a system of partial differential equations and the simulations are in agreement with the recent mice experiments. In some cancer patients, treatment with anti-PD-1 results in rapid progression of the disease, known as hyperprogression disease (HPD). The mathematical model can also explain how this situation arises, and it predicts that HPD may be reversed by combining anti-TGF-β to anti-PD-1. The model is used to demonstrate how the two cancer-specific parameters may serve as biomarkers in predicting the efficacy of combination therapy with PD-1 and TGF-β inhibitors.

Novel patterns of progression upon immunotherapy in other thoracic malignancies and uncommon populations

In the immunotherapy era, considering the prolonged survival benefit and responses observed with immunecheckpoint inhibitors (ICI) in many cancer types, the identification of patients with rapid progression (PD) and deaths upon ICI has found some skepticism and resistance among the scientific community. Nevertheless, an acceleration of tumour during ICI, defined as hyperprogressive disease (HPD), has been recognized across different cancer types and evidence regarding rapid PDs and deaths are emerging in patients with malignant pleural mesothelioma (MPM), small cell lung cancer (SCLC) and thymic malignancies and in uncommon non-small cell lung cancer (NSCLC) populations. Of note, PD and early deaths (ED) rates upon single agent ICI were up to 60% and 30% in MPM and 70% and 38% in SCLC patients, respectively. Similarly, rapid PDs and deaths were observed in clinical trials and retrospective studies including patients with poor performance status (PS), HIV infection and rare NSCLC histologies. Atypical patterns of response, such as pseudoprogression (PsPD) may also occur in other thoracic malignancies (MPM) and in some uncommon populations (i.e., HIV patients), however probably at lower rate compared to HPD. The characterizations of HPD and PsPD mechanisms and the identification of common definition criteria are the next future challenges in this area of cancer research.

Excellent Response to Atezolizumab After Clinically Defined Hyperprogression Upon Previous Treatment With Pembrolizumab in Metastatic Triple-Negative Breast Cancer: A Case Report and Review of the Literature

Immunotherapy with immune checkpoint inhibitors (ICIs), including programmed cell death protein-1 (PD-1) and programmed cell death ligand-1 (PD-L1) inhibitors, has revolutionized the systematic treatment of advanced and metastatic solid tumors. However, the response rate to ICIs is unsatisfactory, and unexpected hyperprogressive disease (HPD) is even observed in a small subgroup of patients. Patients with HPD usually have worsening clinical symptoms and poorer survival, and therapeutic strategies are extremely limited. Here, we presented a patient with HPD who had used a PD-L1 inhibitor and was highly responsive to the sequential use of a PD-1 inhibitor. A 67-year-old woman with metastatic triple-negative breast cancer was treated with pembrolizumab plus chemotherapy after progression on previous multiple-line chemotherapy treatments. After 2 cycles of treatments, she rapidly developed HPD, as confirmed by radiological evaluation and worsening symptoms. At that time, pembrolizumab was discontinued, and she switched to the PD-L1 inhibitor atezolizumab plus chemotherapy. This patient partially responded to atezolizumab plus chemotherapy without experiencing severe drug-related adverse effects. This is the first reported case of metastatic breast cancer in a patient with radiologically confirmed HPD after pembrolizumab therapy in which successful rechallenge with atezolizumab relieved clinical symptoms. Further studies with larger sample sizes involving a deeper translational investigation of HPD are needed to confirm the efficacy and mechanism of sequential application of different ICIs for the clinical management of HPD.

Immune response evaluation criteria in solid tumors for assessment of atypical responses after immunotherapy

In 2017, immune response evaluation criteria in solid tumors (iRECIST) were introduced to validate radiologic and clinical interpretations and to better analyze tumor’s response to immunotherapy, considering the different time of following and response, between this new therapy compared to the standard one. However, even if the iRECIST are worldwide accepted, to date, different aspects should be better underlined and well reported, especially in clinical practice. Clinical experience has demonstrated that in a non-negligible percentage of patients, it is challenging to determine the correct category of response (stable disease, progression disease, partial or complete response), and consequently, to define which is the best management for those patients. Approaching radiological response in patients who underwent immunotherapy, a new uncommon kind of target lesions behavior was found. This phenomenon is mainly due to the different mechanisms of action of immunotherapeutic drug. Therefore, new groups of response have been described in clinical practice, defined as “atypical responses,” and categorized into three new groups: pseudoprogression, hyperprogression, and dissociated response. This review summarizes and reports these patterns, helping clinicians and radiologists get used to atypical responses, in order to identify patients that respond best to treatment.

Single or combined immune checkpoint inhibitors compared to first-line platinum-based chemotherapy with or without bevacizumab for people with advanced non-small cell lung cancer

BACKGROUND

Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis have changed the first-line treatment of people with advanced non-small cell lung cancer (NSCLC). Single-agent pembrolizumab (a PD-1 inhibitor) is currently the standard of care as monotherapy in patients with PD-L1 expression ≥ 50%, either alone or in combination with chemotherapy when PD-L1 expression is less than 50%. Atezolizumab (PD-L1 inhibitor) has also been approved in combination with chemotherapy and bevacizumab (an anti-angiogenic antibody) in first-line NSCLC regardless of PD-L1 expression. The combination of first-line PD-1/PD-L1 inhibitors with anti-CTLA-4 antibodies has also been shown to improve survival compared to platinum-based chemotherapy in advanced NSCLC, particularly in people with high tumour mutational burden (TMB). The association of ipilimumab (an anti CTLA4) and nivolumab (PD-1 inhibitor) has been approved by the US Food and Drug Administration (FDA) in all patients with PD-L1 expression ≥1%. Although these antibodies are currently used in clinical practice, some questions remain unanswered, such as the best-treatment strategy, the role of different biomarkers for treatment selection and the effectiveness of immunotherapy according to specific clinical characteristics.

OBJECTIVES

To determine the effectiveness and safety of first-line immune checkpoint inhibitors (ICIs), as monotherapy or in combination, compared to platinum-based chemotherapy, with or without bevacizumab for people with advanced NSCLC, according to the level of PD-L1 expression.

SEARCH METHODS

We performed an electronic search of the main databases (Cochrane Central Register of Controlled Trials, MEDLINE, Embase) from inception until 31 December 2020 and conferences meetings from 2015 onwards.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) reporting on the efficacy or safety of first-line ICI treatment for adults with advanced NSCLC who had not previously received any anticancer treatment. We included trials comparing single- or double-ICI treatment to standard first-line therapy (platinum-based chemotherapy +/- bevacizumab). All data come from 'international multicentre studies involving adults, age 18 or over, with histologically-confirmed stage IV NSCLC.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed the search results and a fourth review author resolved any disagreements. Primary outcomes were overall survival (OS) and progression-free survival (PFS); secondary outcomes were overall objective response rate (ORR) by RECIST v 1.1, grade 3 to 5 treatment-related adverse events (AEs) (CTCAE v 5.0) and health-related quality of life (HRQoL). We performed meta-analyses where appropriate using the random-effects model for hazard ratios (HRs) or risk ratios (RRs), with 95% confidence intervals (95% CIs), and used the I² statistic to investigate heterogeneity.

MAIN RESULTS

Main results We identified 15 trials for inclusion, seven completed and eight ongoing trials. We obtained data for 5893 participants from seven trials comparing first-line single- (six trials) or double- (two trials) agent ICI with platinum-based chemotherapy, one trial comparing both first-line single- and double-agent ICsI with platinum-based chemotherapy. All trials were at low risk of selection and detection bias, some were classified at high risk of performance, attrition or other source of bias. The overall certainty of evidence according to GRADE ranged from moderate-to-low because of risk of bias, inconsistency, or imprecision. The majority of the included trials reported their outcomes by PD-L1 expressions, with PD-L1 ≥ 50 being considered the most clinically useful cut-off level for decision makers. Also, iIn order to avoid overlaps between various PDL-1 expressions we prioritised the review outcomes according to PD-L1 ≥ 50. Single-agent ICI In the PD-L1 expression ≥ 50% group single-agent ICI probably improved OS compared to platinum-based chemotherapy (hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.60 to 0.76, 6 RCTs, 2111 participants, moderate-certainty evidence). In this group, single-agent ICI also may improve PFS (HR: 0.68, 95% CI 0.52 to 0.88, 5 RCTs, 1886 participants, low-certainty evidence) and ORR (risk ratio (RR):1.40, 95% CI 1.12 to 1.75, 4 RCTs, 1672 participants, low-certainty evidence). HRQoL data were available for only one study including only people with PD-L1 expression ≥ 50%, which suggested that single-agent ICI may improve HRQoL at 15 weeks compared to platinum-based chemotherapy (RR: 1.51, 95% CI 1.08 to 2.10, 1 RCT, 297 participants, low-certainty evidence). In the included studies, treatment-related AEs were not reported according to PD-L1 expression levels. Grade 3-4 AEs may be less frequent with single-agent ICI compared to platinum-based chemotherapy (RR: 0.41, 95% CI 0.33 to 0.50, I² = 62%, 5 RCTs, 3346 participants, low-certainty evidence). More information about efficacy of single-agent ICI compared to platinum-based chemotherapy according to the level of PD-L1 expression and to TMB status or specific clinical characteristics is available in the full text. Double-agent ICI Double-ICI treatment probably prolonged OS compared to platinum-based chemotherapy in people with PD-L1 expression ≥50% (HR: 0.72, 95% CI 0.59 to 0.89 2 RCTs, 612 participants, moderate-certainty evidence). Trials did not report data on HRQoL, PFS and ORR according to PD-L1 groups. Treatment related AEs were not reported according to PD-L1 expression levels. The frequency of grade 3-4 AEs may not differ between double-ICI treatment and platinum-based chemotherapy (RR: 0.78, 95% CI 0.55 to 1.09, I² = 81%, 2 RCTs, 1869 participants, low-certainty evidence). More information about efficacy of double-agent ICI according to the level of PD-L1 expression and to TMB status is available in the full text.

AUTHORS' CONCLUSIONS

Authors' conclusions The evidence in this review suggests that single-agent ICI in people with NSCLC and PD-L1 ≥50% probably leads to a higher overall survival rate and may lead to a higher progression-free survival and overall response rate when compared to platinum-based chemotherapy and may also lead to a lower rate of adverse events and higher HRQoL. Combined ICI in people with NSCLC and PD-L1 ≥50% also probably leads to a higher overall survival rate when compared to platinum-based chemotherapy, but its effect on progression-free survival, overall response rate and HRQoL is unknown due to a lack of data. The rate of adverse events may not differ between groups. This review used to be a living review. It is transitioned out of living mode because current research is exploring ICI in association with chemotherapy or other immunotherapeutic drugs versus ICI as single agent rather than platinum based chemotherapy.

A phase 2a clinical study on the safety and efficacy of individualized dosed mebendazole in patients with advanced gastrointestinal cancer

Mebendazole is used extensively for treatment of local gut helminthic and invasive echinococcus infections. Anticancer effects of mebendazole have been shown in experimental cancer models and in case studies in patients with advanced cancer. Given these observations, the aims of this study were to investigate safety and efficacy of individualized dosed mebendazole in the cancer indication. Patients with treatment refractory gastrointestinal cancer were treated with individualized dose adjusted mebendazole up to 4 g/day to target a serum concentration of 300 ng/ml. Efficacy and safety were assessed by CT-scans, clinical surveillance and blood sampling. Eleven patients were included in the study and 10 started the treatment phase. Two patients stopped treatment prior to and the remaining eight after tumour evaluation by CT-scan at 8 weeks, all due to progressive disease. Four patients also fulfilled criteria suggested for hyperprogression. Only five patients reached the target serum-mebendazole concentration. No severe adverse effects were observed. Individualized dose adjusted mebendazole is safe and well tolerated in patients with advanced cancer but all patients experienced rapid progressive disease. New approaches such as prodrug development and combination with other anticancer drugs seem needed for further exploration of mebendazole as an anticancer drug.

Immune Checkpoint Inhibitors in EGFR-Mutated NSCLC: Dusk or Dawn?

Although immune checkpoint inhibitors (ICIs) that target programmed cell death protein-1/programmed cell death ligand-1 axis have significantly shifted the treatment paradigm in advanced NSCLC, clinical benefits of these agents are limited in patients with EGFR-mutated NSCLC. Several predictive biomarkers (e.g., programmed cell death ligand-1 expression, tumor mutation burden), which have been validated in EGFR-wild type NSCLC, however, are not efficacious in EGFR-mutated tumors, suggesting the unique characteristics of tumor microenvironment of EGFR-mutated NSCLC. Here, we first summarized the clinical evidence on the efficacy of ICIs in patients with EGFR-mutated NSCLC. Then, the cancer immunogram features of EGFR-mutated NSCLC was depicted to visualize the state of cancer-immune system interactions, including tumor foreignness, tumor sensitivity to immune effectors, metabolism, general immune status, immune cell infiltration, cytokines, and soluble molecules. We further discussed the potential subpopulations with EGFR mutations that could benefit from ICI treatment. Lastly, we put forward future strategies to adequately maximize the efficacy of ICI treatment in patients with EGFR-mutated NSCLC in the upcoming era of combination immunotherapies.

Investigation on potential biomarkers of hyperprogressive disease (HPD) triggered by immune checkpoint inhibitors (ICIs)

PURPOSE

This project aimed to survey the clinical characteristics and survivals of hyperprogressive disease (HPD) mediated by immune checkpoint inhibitors (ICIs) in an attempt to explore the potential predictors.

METHODS

After searching PubMed, MEDLINE, Google Scholar and Cochrane Library databases, 12 studies incorporating 1766 individuals were enrolled. The data were analyzed with Review manager 5.3 software.

RESULTS

The results revealed HPD correlated with previous metastatic sites > 2 (OR = 1.86, 95% CI 1.33-2.59, P = 0.0003), liver metastasis (OR = 3.35, 95% CI 2.09-5.35, P < 0.00001), Royal Marsden Hospital (RMH) score ≥ 2 (OR = 2.80, 95% CI 1.85-4.23, P < 0.00001), higher ECOG PS (OR = 1.60, 95% CI 1.13-2.27, P = 0.008) and LDH > upper limits of normal (ULN) (OR = 2.32, 95% CI 1.51-3.58, P = 0.0001). Instead, HPD was unrelated to gender, age, smoking status, PD-L1 expression, therapy, neutrophil-to-lymphocyte ratio, the histology, the status of EGFR, ALK and KRAS in non-small cell lung cancer and HER-2 expression in advanced gastric cancer. Moreover, HPD was evidently correlated with a shorter OS (HR = 2.92, 95% CI 1.79-4.76, P < 0.0001) and PFS (HR = 3.62, 95% CI 2.79-4.68, P < 0.00001). The same phenomena existed in stratified studies based on study regions and tumor types.

CONCLUSIONS

This study demonstrated that HPD was related to the number of prior metastatic sites > 2, liver metastasis, RMH score ≥ 2, higher ECOG PS score and LDH > ULN. Moreover, HPD was correlated with a poor OS and PFS in patients following ICI therapy.

Combination immunotherapy with ipilimumab and nivolumab in patients with advanced adrenocortical carcinoma: a subgroup analysis of CA209-538

Background: Adrenocortical carcinoma is a rare malignancy, with poor prognosis and limited treatment options for patients with advanced disease. Chemotherapy is the current standard first-line treatment, providing only a modest survival benefit. There is only limited treatment experience with immunotherapy using single-agent anti-PD-1/PD-L1 therapy. To date no clinical trials have been reported using combination immunotherapy with anti-CTLA-4 and anti-PD-1 blockade in this patient population. Methods: CA209-538 is a prospective multicentre clinical trial in patients with advanced rare cancers. Participants received the anti-PD-1 antibody nivolumab (3 mg/kg IV) and the anti-CTLA-4 antibody ipilimumab (1 mg/kg IV) every three weeks for four doses, followed by nivolumab (3 mg/kg IV) every two weeks and continued for up to 96 weeks, until disease progression or unacceptable toxicity. Response was assessed every 12 weeks by RECIST version 1.1. Primary endpoint was clinical benefit rate (complete response, partial response, stable disease at 12 weeks). Results: Six patients with adrenocortical carcinoma were enrolled and received treatment. Two patients (33%) have an ongoing partial response (10 and 25 months +) and two patients (33%) stable disease leading to a disease control rate of 66%. Both responders had tumors with a microsatellite instable phenotype. One patient rapidly progressed shortly after enrollment into the trial and did not undergo restaging. Immunotherapy-related toxicity was reported in all patients, with four patients (67%) experiencing grade 3/4 hepatitis leading to discontinuation of treatment. Conclusions: This is the first treatment experience using ipilimumab and nivolumab combination immunotherapy in patients with advanced adrenocortical carcinoma. Durable responses have been observed in a subset of patients suggesting that this treatment regimen should be further investigated in this patient population.

Newly diagnosed follicular lymphoma during pembrolizumab treatment for lung cancer

Malignant lymphoma developing during anti-PD-1 antibody treatment is extremely rare. A 74-year-old female was admitted with left hypochondrial pain. She was diagnosed with squamous cell carcinoma of the right upper lobe of the lung, and had undergone surgery and postoperative chemotherapy three years prior. Needle biopsy of a mediastinal lymph node revealed recurrent lung cancer (LC). Pembrolizumab (PEM) monotherapy was started as salvage treatment. Although her lymphadenopathy improved, thrombocytopenia and splenomegaly developed during treatment with nine doses of PEM. Laboratory findings included anemia, increased lactate dehydrogenase, and soluble interleukin-2 receptor levels of 6379 U/mL. Flow cytometry of peripheral blood and bone marrow showed CD20⁺, κ ≪  λ cell populations. IGH-BCL2 fusion was detected by fluorescence in situ hybridization in bone marrow. Positron emission tomography showed abnormal uptake in tonsils, both cervical lymph nodes, mediastinum (different location from the recurrent LC), spleen, and abdominal cavity. Follicular lymphoma (FL) grade 1/2 was histologically diagnosed by tonsillar biopsy. She achieved a complete metabolic response (CMR) after rituximab monotherapy on PEM discontinuation. Relapsed FL was diagnosed by submandibular gland biopsy four months after restarting PEM and she achieved a second CMR after rituximab-containing chemotherapy. We describe the first case of newly diagnosed FL during PEM treatment.

Expression of PD-L1 in EBV-associated malignancies

Epstein-Barr virus infection is closely related to the occurrence and development of a variety of malignant tumors. Tumor immunotherapy has been combined with modern biological high-tech technology, and has become the fourth cancer treatment mode after surgery, chemotherapy and radiotherapy. In 2013, immunotherapy was named the first of ten scientific breakthroughs by science. It aims to control and destroy tumor cells by stimulating and enhancing autoimmune function. In recent years, immune checkpoint inhibitors (ICIs) targeting PD-L1 have become a research hotspot in the field of cancer. Recent studies have shown that EBV infection can upregulate PD-L1 through complex mechanisms. Further understanding of these mechanisms and prevention of hyperprogressive disease (HPD) can make PD-L1 immune checkpoint inhibitors an effective way of immunotherapy for EBV related malignant tumors.

Fast progression in non-small cell lung cancer: results from the randomized phase III OAK study evaluating second-line atezolizumab versus docetaxel

Background

Treatment-induced accelerated tumor growth is a progression pattern reported with immune checkpoint inhibitors that has never been evaluated in randomized phase III studies because it requires two pretreatment scans. This study aimed to develop clinically relevant and applicable criteria for fast progression (FP), incorporating tumor growth kinetics and early death from disease progression to analyze data from the randomized phase III OAK study.

Methods

The OAK study evaluated the efficacy and safety of atezolizumab versus docetaxel as second-line or third-line treatment for stage IIIb/IV non–small cell lung cancer. FP rates and associated baseline factors were analyzed. FP was defined as either a ≥50% increase in the sum of largest diameters (SLDs) within 6 weeks of treatment initiation or death due to cancer progression within 12 weeks (absent post-baseline scan).

Results

Forty-two of 421 patients (10%) receiving atezolizumab and 37 of 402 (9%) receiving docetaxel had FP. Twenty patients with FP (48%) receiving atezolizumab versus 12 (30%) receiving docetaxel had a ≥50% SLD increase within 6 weeks. FP was significantly associated with an ECOG (Eastern Cooperative Oncology Group) performance status of 1 (vs 0), ≥3 metastatic sites at baseline, and failure of preceding first-line treatment within 6 months, but not with epidermal growth factor receptor mutation, programmed cell death 1 ligand 1 or tumor mutational burden. Overall survival in patients with FP and a ≥50% SLD increase at week 6 was similar with atezolizumab and docetaxel (unstratified HR 0.89 (95% CI 0.41 to 1.92)).

Conclusions

FP rates were similar with atezolizumab and docetaxel in the OAK study, suggesting that FP may not be unique to checkpoint inhibitors, although the underlying mechanisms may differ from those of chemotherapy. Applying the FP criteria to other phase III checkpoint inhibitor trials may further elucidate the risk factors for FP.

Trial registration number

NCT02008227.

Immunotherapy, cancer and PET

The treatment of cancer by immunotherapy has been a revolution, as it is the first strategy that manages to control the disease for prolonged periods of time. Its efficacy is associated with different imaging response patterns and the appearance of new toxicities. We would highlight two patterns of tumour response: pseudoprogression, or growth of tumour lesions after the start of immunotherapy treatment, followed by a significant reduction in lesions, and hyperprogression, acceleration of tumour progression and metastasis early after the start of treatment. The emergence of such patterns has generated new metabolic response criteria, such as PECRIT, PERCIMT, imPERCIST and IPERCIST. Of particular interest are the new immunoPET-specific biomarkers, as they allow the identification of patients presenting the tumour target and are useful for predicting response to immunotherapy.

Definition, Incidence, and Challenges for Assessment of Hyperprogressive Disease During Cancer Treatment With Immune Checkpoint Inhibitors: A Systematic Review and Meta-analysis

IMPORTANCE

Hyperprogressive disease (HPD) is a recognized pattern of rapid tumor progression during immune checkpoint inhibitor (ICI) treatment. Definitions of HPD have not been standardized, posing the risk of capturing different tumoral behaviors.

OBJECTIVES

To provide a systematic summary of definitions and the incidence of HPD in patients undergoing ICI treatment and discuss the challenges of current assessment of HPD.

DATA SOURCES

Articles that evaluated HPD published before March 3, 2020, were identified from MEDLINE and EMBASE.

STUDY SELECTION

Clinical trials and observational studies providing the incidence and definition of HPD from patients with cancer treated with ICIs.

DATA EXTRACTION AND SYNTHESIS

Factors included in the analysis comprised authors, year of publication, cancer type, ICI type, number of previous treatment lines, definition of HPD, time frame used to assess HPD, number of patients with HPD, onset of HPD, and prognosis of patients with HPD. Quantitative and qualitative syntheses for the incidence of HPD were performed.

MAIN OUTCOMES AND MEASURES

Definitions of HPD were categorized and the range of incidence of HPD was evaluated. Subgroup analysis on the incidence of HPD according to the category was performed and the challenges associated with current HPD assessment were evaluated.

RESULTS

Twenty-four studies with 3109 patients were analyzed. The incidence of HPD varied from 5.9% to 43.1%. The definitions were divided into 4 categories based on the calculation of tumor growth acceleration: tumor growth rate ratio (pooled incidence of HPD, 9.4%; 95% CI, 6.9%-12.0%), tumor growth kinetics ratio (pooled incidence, 15.8%; 95% CI, 8.0%-23.7%), early tumor burden increase (pooled incidence, 20.6%; 95% CI, 9.3%-31.8%), and combinations of the above (pooled incidence, 12.4%; 95% CI, 7.3%-17.5%). Hyperprogressive disease could be overestimated or underestimated if the assessment was limited to tumor growth rate or tumor growth kinetics ratio, target lesions, or response evaluation criteria in solid tumors (RECIST)-defined progressors, or if the assessment time frame conformed to RECIST. Study results on clinical outcome were heterogeneous on discriminating patients with HPD from those with natural progressive disease.

CONCLUSIONS AND RELEVANCE

Definitions of HPD appear to be diverse, with the incidence of HPD varying from 5.9% to 43.1% across studies examined in this meta-analysis. Varying incidence and definitions of HPD indicate the need for establishing its uniform and clinically relevant criteria based on currently available evidence.

Radiological dynamics and SITC-defined resistance types of advanced melanoma during anti-PD-1 monotherapy: an independent single-blind observational study on an international cohort

BACKGROUND

Although the Society for Immunotherapy of Cancer (SITC) Immunotherapy Resistance Taskforce recently defined primary and secondary resistance to anti-programmed cell death protein 1 (anti-PD-1) therapy, there is lack of real-world data regarding differences in these resistance subtypes with respect to radiological dynamics and clinical manifestations.

METHODS

We performed single-blind re-evaluations of radiological images by independent radiologists on a retrospectively assembled cohort of patients with advanced melanoma (n=254, median follow-up 31 months) receiving anti-PD-1 monotherapy at Massachusetts General Hospital and Peking University Cancer Hospital. Radiological characteristics and timing at multiple crucial time points were analyzed and correlated with each other and with survival. Primary and secondary resistance was defined as per the SITC Immunotherapy Resistance Taskforce definitions.

RESULTS

The most significant target lesion measurement change took place within the first 3 months after anti-PD-1 initiation. Patients with stable disease with versus without tumor shrinkage at the initial evaluation exhibited distinct disease trajectory, as the rate of further upgrade to a partial or complete remission (CR/PR) was 44% and 0%, respectively. Eleven per cent of PR patients ultimately achieved a CR. In multivariate analyses, deeper response depth was independently associated with a more limited progression pattern, fewer involved organs, lower tumor burden, slower growth rate at disease progression (PD) (all p≤0.001), and longer post-progression survival (PPS) (bivariate analysis, p=0.005). Compared with primary resistance, secondary resistance was associated with less widespread PD pattern, lower tumor burden and slower tumor growth (all p≤0.001). Patients with secondary resistance were less likely to receive further systemic therapy (28% vs 57%, p<0.001) yet had significantly better PPS (HR 0.503, 95% CI 0.288 to 0.879, p=0.02).

CONCLUSIONS

Radiological dynamics were variable, yet significantly correlated with survival outcomes. SITC-defined primary and secondary resistance are distinct clinical manifestations in patients with melanoma, suggesting the possibility of resistance-type-based therapeutic decision-making and clinical trial design, once further validated by future prospective studies.

Efficacy and safety of anti-PD-1/PD-L1 combinations versus standard of care in cancer: a systematic review and meta-analysis

Immune checkpoint inhibitors (ICIs) as monotherapy in different solid tumors showed an early detrimental effect in a subset of patients reflected by the early crossover of the progression-free survival (PFS) curves. Currently, combination therapies with ICIs added to chemotherapy or targeted therapy are expanding the landscape of metastatic solid tumors. We have examined the benefits and risks of adding ICIs to the standard of care (SOC) versus SOC alone.

A search of randomized clinical trials (RCTs) comparing ICIs combinations versus the corresponding SOC in different metastatic tumors according to the PRISMA guidelines was performed. Selected endpoints included PFS, time-to-response (TTR), overall survival (OS), overall response rate (ORR), and ≥ grade 3 adverse events (AEs). Subgroup analyses based on backbone treatment and tumor type were included.

A total of 10536 patients (19 studies) were included (ICIs-arm: 5596 patients; SOC-arm: 4940 patients). Globally, PFS, OS, and ORR results favored ICIs-arm. No differences in terms of TTR were found between arms. ICI-arm was associated with a slight increase of ≥ G3 AEs (relative risk: 1.07). The results in multiple myeloma patients are controversial in favor of ICIs combinations.

Adding ICIs to SOC benefits a greater number of patients, prolonging survival with no early detrimental effect. The toxicity profile is safe, with a mild increase of high-grade manageable AEs.

Non-canonical PD-1 signaling in cancer and its potential implications in clinic

Programmed cell death 1 (PD-1)-based immunotherapy has revolutionized the treatment of various cancers. However, only a certain group of patients benefit from PD-1 blockade therapy and many patients succumb to hyperprogressive disease. Although, CD8 T cells and conventional T cells are generally considered to be the primary source of PD-1 in cancer, accumulating evidence suggests that other distinct cell types, including B cells, regulatory T cells, natural killer cells, dendritic cells, tumor-associated macrophages and cancer cells, also express PD-1. Hence, the response of patients with cancer to PD-1 blockade therapy is a cumulative effect of anti-PD-1 antibodies acting on a myriad of cell types. Although, the contribution of CD8 T cells to PD-1 blockade therapy has been well-established, recent studies also suggest the involvement of non-canonical PD-1 signaling in blockade therapy. This review discusses the role of non-canonical PD-1 signaling in distinct cell types and explores how the available knowledge can improve PD-1 blockade immunotherapy, particularly in identifying novel biomarkers and combination treatment strategies.

Imaging challenges of immunotherapy and targeted therapy in patients with brain metastases: response, progression, and pseudoprogression

The advent of immunotherapy using immune checkpoint inhibitors (ICIs) and targeted therapy (TT) has dramatically improved the prognosis of various cancer types. However, following ICI therapy or TT-either alone (especially ICI) or in combination with radiotherapy-imaging findings on anatomical contrast-enhanced MRI can be unpredictable and highly variable, and are often difficult to interpret regarding treatment response and outcome. This review aims at summarizing the imaging challenges related to TT and ICI monotherapy as well as combined with radiotherapy in patients with brain metastases, and to give an overview on advanced imaging techniques which potentially overcome some of these imaging challenges. Currently, major evidence suggests that imaging parameters especially derived from amino acid PET, perfusion-/diffusion-weighted MRI, or MR spectroscopy may provide valuable additional information for the differentiation of treatment-induced changes from brain metastases recurrence and the evaluation of treatment response.

Evaluation of Combination Nivolumab and Ipilimumab Immunotherapy in Patients With Advanced Biliary Tract Cancers: Subgroup Analysis of a Phase 2 Nonrandomized Clinical Trial

Importance

Biliary tract cancers represent a rare group of malignant conditions with very limited treatment options. Patients with advanced disease have a poor outcome with current therapies.

Objective

To evaluate the efficacy and safety of combination immunotherapy with nivolumab and ipilimumab in patients with advanced biliary tract cancers.

Design, Setting, and Participants

The CA209-538 prospective multicenter phase 2 nonrandomized clinical trial included patients with advanced rare cancers including patients with biliary tract cancers. This subgroup analysis evaluated 39 patients from CA209-538 with biliary tract cancers who were enrolled from December 2017 to December 2019. Most of the patients (n = 33) had experienced disease progression after 1 or more lines of therapy and had tumor tissue available for biomarker research.

Interventions

Patients received treatment with nivolumab at a dose of 3 mg/kg and ipilimumab at 1 mg/kg every 3 weeks for 4 doses, followed by nivolumab 3 mg/kg every 2 weeks and continued for up to 96 weeks until disease progression or the development of unacceptable toxic events.

Main Outcomes and Measures

The primary end point was disease control rate (complete remission, partial remission, or stable disease) as assessed by RECIST 1.1.

Results

Among the 39 patients included in this subgroup analysis of a phase 2 clinical trial (20 men, 19 women; mean [range] age, 65 [37-81] years), the objective response rate was 23% (n = 9) with a disease control rate of 44% (n = 17); all responders had received prior chemotherapy, and none had a microsatellite unstable tumor. Responses were exclusively observed in patients with intrahepatic cholangiocarcinoma and gallbladder carcinoma. The median duration of response was not reached (range, 2.5 to ≥23 months). The median progression-free survival was 2.9 months (95% CI, 2.2-4.6 months), and overall survival was 5.7 months (95% CI, 2.7-11.9 months). Immune-related toxic events were reported in 49% of patients (n = 19), with 15% (n = 6) experiencing grade 3 or 4 events.

Conclusions and Relevance

This subgroup analysis of a phase 2 clinical trial found that combination immunotherapy with nivolumab and ipilimumab was associated with substantial positive outcomes patients with advanced biliary tract cancers. This treatment compares favorably to single-agent anti-programmed cell death protein 1 (anti-PD-1) therapy and warrants further investigation. Ongoing translational research is focused on identifying biomarkers that can predict treatment response.

Trial Registration

ClinicalTrials.gov Identifier: NCT02923934.

Modulation of PD-1/PD-L1 axis in myeloid-derived suppressor cells by anti-cancer treatments

Immuno checkpoint blockade (ICB) targeting the PD-1/PD-L1 axis is the main breakthrough for the treatment of several cancers. Nevertheless, not all patients benefit from this treatment and clinical response not always correlates with PD-L1 expression by tumor cells. The tumor microenvironment, including myeloid derived suppressor cells (MDSCs), can influence therapeutic resistance to ICB. MDSCs also express PD-L1, which contributes to their suppressive activity. Moreover, anticancer therapies including chemotherapy, radiotherapy, hormone- and targeted- therapies can modulate MDSCs recruitment, activity and PD-L1 expression. Such effects can be induced also by innovative anticancer treatments targeting metabolism and lifestyle. The outcome on cancer progression can be either positive or negative, depending on tumor type, treatment schedule and possible combination with ICB. Further studies are needed to better understand the effects of cancer therapies on the PD-1/PD-L1 axis, to identify patients that could benefit from combinatorial regimens including ICB or that rather should avoid it.

The cutting-edge progress of immune-checkpoint blockade in lung cancer

Great advances in immune checkpoint blockade have resulted in a paradigm shift in patients with lung cancer. Immune-checkpoint inhibitor (ICI) treatment, either as monotherapy or combination therapy, has been established as the standard of care for patients with locally advanced/metastatic non-small cell lung cancer without EGFR/ALK alterations or extensive-stage small cell lung cancer. An increasing number of clinical trials are also ongoing to further investigate the role of ICIs in patients with early-stage lung cancer as neoadjuvant or adjuvant therapy. Although PD-L1 expression and tumor mutational burden have been widely studied for patient selection, both of these biomarkers are imperfect. Due to the complex cancer-immune interactions among tumor cells, the tumor microenvironment and host immunity, collaborative efforts are needed to establish a multidimensional immunogram to integrate complementary predictive biomarkers for personalized immunotherapy. Furthermore, as a result of the wide use of ICIs, managing acquired resistance to ICI treatment remains an inevitable challenge. A deeper understanding of the underlying biological mechanisms of acquired resistance to ICIs is helpful to overcome these obstacles. In this review, we describe the cutting-edge progress made in patients with lung cancer, the optimal duration of ICI treatment, ICIs in some special populations, the unique response patterns during ICI treatment, the emerging predictive biomarkers, and our understanding of primary and acquired resistance mechanisms to ICI treatment.

Comparative incidence of immune-related adverse events and hyperprogressive disease in patients with non-small cell lung cancer receiving immune checkpoint inhibitors with and without chemotherapy

Immune-related adverse events (irAEs) and hyperprogressive disease (HPD) are serious problems arising in the early period of monotherapy (MT) with programmed cell death protein 1 (PD-1) and programmed cell death ligand1 (PD-L1) inhibitors. However, the frequency and clinical features of these problems in patients receiving combination therapy (CT) with cytotoxic chemotherapy in addition to these agents remain unclear. We retrospectively screened patients with pathologically confirmed advanced or recurrent non-small cell lung cancer (NSCLC) who had received PD-1/PD-L1 inhibitors at Kurume University Hospital between February 2016 and March 2020. We recruited 210 patients, of whom 172 (81.9%) had received PD-1/PD-L1 inhibitor MT and 38 (18.1%) had received CT. The incidence of irAE during the 3 months after treatment initiation was significantly higher in the MT group (57 of 172, 33.1%) than in the CT group (6 of 38, 15.8%) (p = 0.049). During the same period, the incidence of pneumonitis was also higher in the MT group (18 of 172, 10.9%) than in the CT group (0 of 38) (p = 0.049). A similar trend was observed in patients who had received these treatments on a first line basis. The HPD rate was significantly lower in the CT group (1 of 34, 2.9%) than in the MT group (25 of 142, 17.6%) (p = 0.031). The incidences of HPD and irAE, especially pneumonitis, during 3 months after treatment initiation were relatively lower in the CT group than in the MT group. The mechanisms underlying these differences warrant further study.