Management of Oncogene Driven Locally Advanced Unresectable Non-small Cell Lung Cancer.

INTRODUCTION: The current standard of care of locally advanced non-small cell lung cancer (LA-NSCLC) is concurrent chemoradiation, followed by consolidation durvalumab. However, there is evidence that the efficacy of chemoradiation and also immunotherapy in many oncogene-positive LA-NSCLC are attenuated, and dependent on the subgroup. AREAS COVERED: We will firstly review the outcomes of standard-of-care therapy in oncogene-driven LA-NSCLC. We looked at various oncogene driven subgroups and the tumor microenvironment that may explain differential response. Finally, we review the role of targeted therapy in the treatment of LA-NSCLC. EXPERT OPINION: Each oncogene-positive subgroup should be treated as its own entity, and continued efforts should be undertaken to incorporate targeted therapy, which is likely to yield superior survival outcomes if trial design can be optimized and toxicities can be managed.

Expression of EGFR and conformational forms of EGFR in malignant pleural mesothelioma and its impact on survival.

AIM: Conformational forms of the epidermal growth factor receptor (EGFR) are pro-tumorigenic. The prevalence and impact of conformational forms of EGFR in malignant mesothelioma (MM) is unknown. We investigated expression of EGFR and conformational forms of EGFR by immunohistochemistry using EGFR-targeting monoclonal antibodies (mAb). In addition, EGFR gene amplification was investigated by fluorescent in-situ hybridization (FISH). Findings were correlated with survival. METHODS: Patients treated between 1988 and 2014 were identified from the thoracic surgery database of the Austin Hospital, Melbourne, Australia. Tissue microarrays (TMAs) were constructed, subjected to wild type (wt) EGFR IHC staining and FISH analysis. Conformational and mutation forms of EGFR were detected by IHC using mAb806, and LMH-151 which detects EGFRVIII. `H-scores` were derived and EGFR expression correlated with survival by Kaplan-Meier and log rank analysis. RESULTS: WtEGFR expression was seen in 93 % (299/321) of cases with overexpression (defined as an H-score ≥200) seen in more than half of cases (64 %). EGFR overexpression in MM was seen more commonly in the epithelioid subtype. EGFR overexpression was not associated with true EGFR amplification, although multiple copies were appreciated in samples with polysomy. EGFR expression did not correlate with survival. A conformational form of EGFR associated with EGFR dysregulation was found in 8.2 % of cases, and patients with these tumors had a trend towards a poorer outcome. No cases of the EGFRVIII mutation were identified. CONCLUSION: MM consistently demonstrated high expression of EGFR, with a subset of tumors showing conformational EGFR forms consistent with EGFR dysregulation, but withoutEGFR amplification or EGFR VIII mutation. wtEGFR expression did not influence survival. The impact of EGFR conformation on survival warrants further investigation.

Targeting and Efficacy of Novel mAb806-Antibody-Drug Conjugates in Malignant Mesothelioma.

Epidermal growth factor receptor (EGFR) is highly overexpressed in malignant mesothelioma (MM). MAb806 is a novel anti-EGFR antibody that selectively targets a tumor-selective epitope. MAb806-derived antibody drug conjugates (ADCs), ABT-414, ABBV-221 and ABBV-322, may represent a novel therapeutic strategy in MM. EGFR and mAb806 epitope expressions in mesothelioma cell lines were evaluated using an array of binding assays, and the in vitro cell effects of ABT-414 and ABBV-322 were determined. In vivo therapy studies were conducted in mesothelioma xenograft and patient-derived xenograft (PDX) tumor models. We also performed biodistribution and imaging studies to allow the quantitative targeting of MM by mAb806 using a 89Zr-labeled immunoconjugate-ch806. A high EGFR expression was present in all mesothelioma cell lines evaluated and mAb806 binding present in all cell lines, except NCIH-2452. ABT-414 and ABBV-322 resulted in significant tumor growth inhibition in MM models with high EGFR and mAb806 epitope expressions. In contrast, in an EGFR-expressing PDX model that was negative for the mAb806 epitope, no growth inhibition was observed. We demonstrated the specific targeting of the mAb806 epitope expressing MM tumors using 89Zr-based PET imaging. Our data suggest that targeting EGFR in MM using specific ADCs is a valid therapeutic strategy and supports further investigation of the mAb806 epitope expression as a predictive biomarker.

Analysis of angiogenic and stromal biomarkers in a large malignant mesothelioma cohort.

BACKGROUND: Malignant mesothelioma (MM) is an aggressive malignancy of the pleura and other mesothelial membranes. Agents targeting vascular endothelial growth factor (VEGF) such as bevacizumab; and multi-kinase inhibitors such as nintedanib [angiokinase inhibitor of VEGF, platelet-derived growth factor (PDGF) receptor and fibroblast growth factor receptor (FGFR)] have recently demonstrated efficacy in MM. METHODS: Tissue microarrays (TMAs) were created from formalin-fixed, paraffin-embedded tissue samples obtained from 326 patients with MM who were treated surgically. PDGF-CC, FGFR-1, VEGF and CD31 expression were analysed by immunohistochemical (IHC) staining. The H-score method assigned a score of 0-300 to each sample, based on the percentage of cells stained at different intensities. CD31 was evaluated via Chalkley's method to evaluate microvessel density. We evaluated the association between expression of the biomarkers, clinicopathological factors and outcomes, in patients with MM. RESULTS: CD31 high (≥5) was seen in only 31/302 (10.3%) irrespective of histology. PDGF-CC high (≥150) was seen in 203 /310 (65%) of all samples. VEGF high (≥80) was seen in 219/322 (68%) of all MM with 143/209 (68%) of epithelioid histology. FGFR-1 high (≥40) was seen in 127/310 (41%) of all MM. There was no association of VEGF and FGFR-1 IHC with survival nor differences between histological subtypes. There was a non-significant trend towards poorer survival in epithelioid tumours with increased PDGF-CC expression (OS 18.5 vs 13.2 months; HR 0.7928; 95% CI 0.5958 to 1.055, P = 0.1110). High CD31 score was associated with significantly poorer survival (OS 12 vs 8.6 months; HR 0.48; 95% CI 0.2873 to 0.7941, P = 0.0044). Of the 31 patients with high CD31 scores; 23/31 (74%) were also high for PDGF-CC and 20/31 (64%) with high VEGF scores. CD31 was found to be an independent prognostic factor in multivariate analysis (HR 1.540; 95% CI 1.018 to 2.330; p = 0.041). CONCLUSIONS: High CD31 was an independent poor prognostic factor and high PDGF-CC expression was associated with poor survival in MM. Abrogating these pathways may have prognostic implications.

Targeting Multiple EGFR-expressing Tumors with a Highly Potent Tumor-selective Antibody-Drug Conjugate.

ABBV-321 (serclutamab talirine), a next-generation EGFR-targeted antibody-drug conjugate (ADC) incorporates a potent pyrrolobenzodiazepine (PBD) dimer toxin conjugated to the EGFR-targeting ABT-806 affinity-matured AM1 antibody. ABBV-321 follows the development of related EGFR-targeted ADCs including depatuxizumab mafodotin (depatux-m, ABT-414), ABT-806 conjugated to monomethyl auristatin F (MMAF), and ABBV-221 (losatuxizumab vedotin), AM1 antibody conjugated to monomethyl auristatin E (MMAE). The distinct tumor selectivity of ABBV-321 differentiates it from many previous highly active antibody PBD conjugates that lack a therapeutic window. Potency of the PBD dimer, combined with increased binding of AM1 to EGFR-positive tumor cells, opens the possibility to target a wide array of tumors beyond those with high levels of EGFR overexpression or amplification, including those insensitive to auristatin-based ADCs. ABBV-321 exhibits potent antitumor activity in cellular and in vivo studies including xenograft cell line and patient-derived xenograft glioblastoma, colorectal, lung, head and neck, and malignant mesothelioma tumor models that are less sensitive to depatux-m or ABBV-221. Combination studies with ABBV-321 and depatux-m suggest a promising treatment option permitting suboptimal, and potentially better tolerated, doses of both ADCs while providing improved potency. Collectively, these data suggest that ABBV-321 may offer an extended breadth of efficacy relative to other EGFR ADCs while extending utility to multiple EGFR-expressing tumor indications. Despite its highly potent PBD dimer payload, the tumor selectivity of ABBV-321, coupled with its pharmacology, toxicology, and pharmacokinetic profiles, support continuation of ongoing phase I clinical trials in patients with advanced EGFR-expressing malignancies.

Epidermal growth factor receptor (EGFR)-targeted therapies in mesothelioma.

INTRODUCTION: Malignant mesothelioma (MM) is an aggressive malignancy arising from the mesothelial cells lining the pleura and other serosal membranes. It is associated with an extremely poor prognosis and has limited therapeutic options. AREAS COVERED: Epidermal growth factor receptor (EGFR) is known to be highly overexpressed in mesothelioma with reported EGFR overexpression between 44 to 97%. Given this, several anti-EGFR agents have been trialed in mesothelioma. In this review, we provide an overview of the current available data on anti-EGFR therapies in MM and future directions of investigation with these targeted agents in MM. EXPERT OPINION: While many anti-EGFR therapies have failed to show significant efficacy in the management of MM, the pathway is biologically active and its abrogation preclinically points toward it being a valid target. Toward targeting the pathway, many novel EGFR-based therapies are still being investigated. Current ongoing research of interest in MM include EGFR-targeted nanotechnology approach for drug delivery, antibodies targeting the extracellular EGFR and potentially anti-EGFR antibody drug conjugates.

Timing of brain metastases development in metastatic renal cell cancer patients treated with targeted therapies and survival outcomes: An Australian multicenter study.

AIM: Targeted therapy (TT) has improved survival for metastatic renal cell carcinoma (mRCC). However, survival is usually limited if brain metastases (BMs) develop. We aimed to evaluate survival outcomes in mRCC patients based on timing of BM diagnosis. METHODS: We conducted a multicenter, retrospective study of mRCC patients with BM who received TT at any point between 2005 and 2014. We determined overall survival (OS) from stage IV diagnosis, TT initiation and BM diagnosis, and prognostic factors. Patients were grouped into three categories: synchronous-BM, metachronous-BM diagnosed while conservatively managed (metachronous-BM before TT) and metachronous-BM diagnosed during TT. Survival was calculated by Kaplan-Meier method and predictors were calculated using Cox hazards regression. RESULTS: Incidence of BM was 17% in mRCC patients treated with TT (two centers). Fifty-four mRCC-BM patients were identified from five tertiary centers. Twenty-eight percentage (15/54) had synchronous-BM, 28% (15/54) had metachranous-BM before TT and 44% (24/54) had metachronous-BM during TT. Most had central nervous system (CNS) symptoms at BM diagnosis (78%; 42/54). Median OS from stage IV diagnosis, TT commencement and BM diagnosis was 28 months (95% confidence interval [CI] 16-43), 19 months (95% CI 9-26) and 9 months (95% CI 5-16), respectively. Synchronous-BM group trended toward poorer survival from TT commencement (P = 0.06). Metachronous-BM during TT group had lower survival from BM diagnosis than synchronous-BM and metachronous-BM before TT group (P < 0.001). Eight of 50 deaths (16%) were from neurological complications. The presence of CNS symptoms did not predict worse survival from stage IV diagnosis (P = 0.73). CONCLUSION: In patients with mRCC, the development of BM while on TT portends shorter prognosis compared with synchronous diagnosis of BM at stage IV disease or metachronous BM developed prior to commencing TT. The presence of CNS symptoms does not predict worse survival.

Personalized Chemosensitivity Assays for Mesothelioma: Are They Worth the Effort?

Cell lines formed from an individual's tumor can be used to predict response to specific therapies and determine genomic predictors. For mesothelioma, where chemotherapy remains the backbone of current therapeutic paradigms, such assays could be used to treat patients with the most effective agents specific to their "chemical profile." Clin Cancer Res; 24(7); 1513-5. ©2018 AACRSee related article by Schunselaar et al., p. 1761.

The utility of routine pre-chemotherapy screening with cardiac gated blood pool scan for patients at low risk of anthracycline toxicity.

Background Anthracycline-based chemotherapy is used in many malignancies. Current recommendations by several groups suggest cardiac monitoring prior to and during anthracycline therapy. We aim to review the usefulness of baseline cardiac screening for left ventricular ejection fraction to assess if it had any impact on chemotherapy decisions in patients to be treated with anthracycline-based regimens or any beneficial effect upon outcomes. Methods We conducted a retrospective three-year audit of cancer patients who underwent GBPS prior to anthracycline (doxorubicin) chemotherapy. Subjects were identified via records from the Department of Nuclear Medicine. Pharmacy dispensing records identified those who received doxorubicin. Patient demographics, cancer type, cardiac risk factors, GBPS ejection fraction (EF), and cumulative anthracycline dose were collected. Results From 1 August 2009 to 31 July 2012, 179 patients underwent GBPS pre-doxorubicin chemotherapy. The mean age was 59 years (range 21-89 years), with 51% being males. Only two patients (1.1%) had an abnormal EF < 50%, while 33 patients (18%) had an EF 51-59% and 144 patients (80%) had EF ≥ 60%. The two patients with reduced baseline EF still received anthracycline-based chemotherapy. All 135 patients without any known cardiovascular risk factors had normal EFs. The total number of patients who received anthracycline chemotherapy during the same period was 207. Thus 28 patients (13%) commenced anthracycline without a prior GBPS. Conclusion Only 1.1% of the screened patients had EF < 50%. These two patients still received doxorubicin chemotherapy despite a compromised EF, as their treating clinicians believed that the benefits of chemotherapy outweighed the risk of potential cardiac toxicity. Our audit questions the practice of routine cardiac evaluation pre-anthracycline screening with GBPS. We propose that routine screening only be requested if cardiac risk factors are present.

Targeting the vasculature: anti-angiogenic agents for malignant mesothelioma.

INTRODUCTION: Malignant mesothelioma (MM) is an aggressive malignancy of the pleura and other serosal membranes originating from mesothelial cells that, despite decades of research, continues to have limited therapeutic options and is associated with a poor prognosis. Areas covered: MMs induce a strong inflammatory response that is also associated with neoangiogenesis and activation of proangiogenic factors. Given this, several anti-angiogenic agents have been trialled in a variety of malignancies including mesothelioma. Herein we summarise the role of angiogenesis in MM and the current available data targeting these pathways. Expert commentary: The addition of bevacizumab to cisplatin/pemetrexed chemotherapy is currently a therapeutic option with a proven 2.7 month overall survival benefit in fit patients less than 75. Other antiangiogenics such as nintedinib show early promise, although the Phase III trial results are eagerly awaited before this therapy enters treatment paradigms. Beyond this, it is likely that combinations of antiangiogenics with immunotherapies will be investigated in future studies.

Temporal changes of EGFR mutations and T790M levels in tumour and plasma DNA following AZD9291 treatment.

AZD9291, a T790M specific epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), has demonstrated impressive response rates in tumours harbouring the EGFR T790M resistance mutation. Emergence of resistance to AZD9291 has been shown to occur through several different mechanisms including the development of new mutations (e.g. C797S) in the EGFR tyrosine kinase domain. We studied two patients with paired tumour biopsies and blood samples pre- and post-progression on AZD9291 to explore possible resistance mechanisms. Pre- and Post-AZD9291 tumour biopsies as well as serial plasma samples were collected from two patients on the AURA clinical study (AZD9291 First Time in Patients Ascending Dose study). Droplet digital PCR (ddPCR) assays were used to quantify T790M, the driver EGFR mutation, and the C797S mutation in genomic DNA from paired tumour biopsies and plasma cell-free DNA. In the first patient, both EGFR T790M and L858R became undetectable in the plasma within 1 month after treatment with AZD9291. However, the T790M and the original L858R mutation re-emerged with radiologically confirmed resistance to AZD9291. In patient two, the levels of T790M were undetectable at the time of radiological resistance to AZD9291 but increasing levels of the original EGFR exon 19 deletion was detected. MET amplification was detected in a biopsy performed on progression. The EGFR C797S mutation was not detected in either patient at the time of relapse. ddPCR of cell free DNA enables real time monitoring of patients on 3rd generation TKIs. As resistance mechanisms are variable, monitoring levels of the initial activating EGFR mutation may facilitate more reliable detection of progression.

Current and Evolving Methods to Visualize Biological Data in Cancer Research.

Although the measurements of clinical outcomes for cancer treatments have become diverse and complex, there remains a need for clear, easily interpreted representations of patients' experiences. With oncology trials increasingly reporting non-time-to-event outcomes, data visualization has evolved to incorporate parameters such as responses to therapy, duration and degree of response, and novel representations of underlying tumor biology. We review both commonly used and newly developed methods to display outcomes in oncology, with a focus on those that have evolved to represent complex datasets.

Severe Psoriasis Flare After Anti-Programmed Death Ligand 1 (PD-L1) Therapy for Metastatic Non-Small Cell Lung Cancer (NSCLC).

Immunomodulatory agents that target PD-1 and its ligand (PD-L1) are being increasingly used in the management of lung cancer. Potential immune-related adverse events include dermatological complications which mostly are of low grade severity. The use of immune checkpoint inhibitors may lead to the exacerbation of autoimmune conditions. We report a case of a documented psoriasis flare with anti-PD-1 treatment for lung cancer.

Prevalence and natural history of ALK positive non-small-cell lung cancer and the clinical impact of targeted therapy with ALK inhibitors.

Improved understanding of molecular drivers of carcinogenesis has led to significant progress in the management of lung cancer. Patients with non-small-cell lung cancer (NSCLC) with anaplastic lymphoma kinase (ALK) gene rearrangements constitute about 4%-5% of all NSCLC patients. ALK+ NSCLC cells respond well to small molecule ALK inhibitors such as crizotinib; however, resistance invariably develops after several months of treatment. There are now several newer ALK inhibitors, with the next generation of agents targeting resistance mutations. In this review, we will discuss the prevalence and clinical characteristics of ALK+ lung cancer, current treatment options, and future directions in the management of this subset of NSCLC patients.