A heterogeneous tumor immune microenvironment of uncommon epidermal growth factor receptor mutant non-small cell lung cancer.

Common epidermal growth factor receptor (EGFR) mutations are usually not considered for immunotherapy in non-small cell lung cancer (NSCLC) due to poor efficacy. However, whether uncommon EGFR mutations are suitable for immunotherapy has not been thoroughly studied. Thus, we explored the tumor immune microenvironment (TME) features in uncommon EGFR mutant NSCLC. In this study, a total of 41 patients with EGFR mutations were included, the majority (85.4%) of whom were stage I. Among them, 22 patients harbored common mutations, while 19 patients presented with uncommon mutations. Compared with common mutations, uncommon mutations exhibited more infiltrating T cells and fewer M2 macrophages, upregulated expression of antigen processing and a presentation pathway. Unsupervised clustering based on the mIF profile identified two classes with heterogeneous TME in uncommon mutations. Class 1 featured the absence of PD-1+ cytotoxic T cell infiltration, and class 2 displayed a hotter TME because of the downregulated expression of hypoxia (p < 0.001), oxidative phosphorylation (p = 0.009), and transforming growth factor beta signaling (p = 0.01) pathways as well as increased expression of CTLA4 (p = 0.001) and PDCD1 (p = 0.004). The association of CTLA4 and PDCD1 with TME profiles was validated in a TCGA lung adenocarcinoma cohort with uncommon EGFR mutations. Our study reveals the distinct and heterogeneous TME features in uncommon EGFR mutant NSCLC.

Non-small cell lung cancer: an update on emerging EGFR-targeted therapies.

INTRODUCTION: Current research in EGFR-mutated NSCLC focuses on the management of drug resistance and uncommon mutations, as well as on the opportunity to extend targeted therapies' field of action to earlier stages of disease. AREAS COVERED: We conducted a review analyzing literature from the PubMed database with the aim to describe the current state of art in the management of EGFR-mutated NSCLC, but also to explore new strategies under investigation. To this purpose, we collected recruiting phase II-III trials registered on Clinicaltrials.govand conducted on EGFR-mutated NSCLC both in early and advanced stage. EXPERT OPINION: With this review, we want to provide an exhaustive overview of current and new potential treatments in EGFR-mutated NSCLC, with emphasis on the most promising newly investigated strategies, such as association therapies in the first-line setting involving EGFR-TKIs and chemotherapy (FLAURA2) or drugs targeting different driver pathways (MARIPOSA). We also aimed at unearthing challenges to achieve in this field, specifically the need to fully exploit already available compounds while developing new ones, the management of new emerging toxicities and the necessity to improve our biological understanding of the disease to design trials with a solid scientific rationale and to allow treatment personalization such in case of uncommon mutations.

Identification and antifungal susceptibility profile of uncommon yeast species at Fattouma Bourguiba University Hospital in Tunisia.

Despite the severe impact of uncommon yeast fungal infections and the pressing need for more research on the topic, there are still few studies available on the identification, epidemiology, and susceptibility profile of those pathogens. The aims of the current study were to define the profile of uncommon yeast species at Fattouma Bourguiba University Hospital using phenotypic, molecular, and proteomic methods and to study their antifungal susceptibility profile. Pre-identified uncommon yeast species were collected from 2018 to 2021. These isolates were further identified using phenotypic methods (ID32C® system and Vitek2® YST), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), and sequencing. The antifungal susceptibility profile was studied using the reference CLSI broth microdilution method. In total, 30 strains were collected during the study period. Referring to the sequencing, the most isolated uncommon species were Saprochaete capitata, Candida lusitaniae, Candida kefyr, Candida inconspicua, and Candida guilliermondii. A total of 90% of isolates were correctly identified by MALDI-TOF MS compared to 76.7% and 63.3% by ID32® C and VITEK® 2 YST, respectively. The isolated species showed variable responses to antifungals. Candida guilliermondii showed increased azole minimum inhibitory concentrations. Misidentification of uncommon yeast species was common using commercial phenotypic methods. The high percentage of concordance of MALDI-TOF results with sequencing highlights its high performance and usefulness as a routine diagnosis tool.

There is still little information on the epidemiology of uncommon emergent yeasts, although their implication in severe diseases and mainly invasive infections. Thus, the importance of an accurate identification and antifungal susceptibility testing for a better monitoring of related infections.

Genomic characterization of an uncommon Delftia acidovorans isolate obtained from a Bulgarian immunocompetent outpatient diagnosed with bronchitis.

Delftia acidovorans is an aerobic, non-fermenting Gram-negative bacterium (NFGNB), found in soil, water and hospital environments. It is rarely clinically significant, most commonly affecting hospitalized or immunocompromised patients. The present study aimed to explore the genomic characteristics of a Bulgarian clinical D. acidovorans isolate (designated Dac759) in comparison to all strains of this species with available genomes in the NCBI Genome database (n = 34). Dac759 was obtained in 2021 from the sputum of a 65-year-old female immunocompetent outpatient with bronchitis. Species identification using MALDI-TOF mass spectrometry, antimicrobial susceptibility testing, whole-genome sequencing (WGS), and phylogenomic analysis were performed. The isolate demonstrated high-level resistance to colistin (16 mg L-1); resistance to gentamicin; reduced susceptibility to piperacillin, piperacillin-tazobactam, ceftazidime, cefepime, ciprofloxacin, and levofloxacin; and susceptibility to imipenem, meropenem, amikacin, and tobramycin. The observed genome size (6.43 Mb) and GC content (66.76%) were comparable with the accessible data from sequenced D. acidovorans genomes. A limited number of resistance determinants were identified in the assembled genome as follows: blaOXA-459, emrE, oqxB, and mexCD-oprJ. The phylogenomic analysis indicated a high heterogenicity of the included D. acidovorans genomes. In conclusion, to the best of our knowledge, this is the first documented case of a clinically relevant D. acidovorans isolate in Bulgaria. Unlike the majority of reports in the literature, Dac759 affected a patient with no malignancies or other preexisting comorbidities. With this in mind, its genome sequence is a valuable resource for the fundamental study of uncommon bacterial pathogens of public health importance.

A patient with anti-f in India identified by extensive immunohematologic workup.

Anti-f is produced by exposure to the compound antigen ce (f) on red blood cells (RBCs), expressed when both c and e are present on the same protein (cis position). Although anti-f was discovered in 1953, there are few cases reported worldwide because the presence of anti-f is often masked by anti-c or anti-e and is not generally found as a single antibody. In the present case, anti-f was identified by using three-cell screening and 11-cell identification panels. The identification of anti-f was further supported by additional testing, including (1) Rh antigen typing; (2) antibody identification panels (enzyme-treated panel [ficin] and an in-house-constructed Rh panel); (3) look-back and phenotyping of donor RBC units, which were responsible for alloimmunization; and (4) molecular testing of the patient's RBCs.

Real-world clinical analysis in 190 advanced NSCLC patients with uncommon EGFR mutations: A multi-center study.

Differently from epidermal growth factor receptor (EGFR) 19Del and L858R mutations, the panoramic description of uncommon EGFR mutations is far from mature. Our understanding of its population characteristics, treatment response, and drug resistance mechanisms needs urgent expansion and deepening. Our study enrolled 437 patients with non-small-cell lung cancer from four clinical centers and who had uncommon EGFR mutations. The clinical characteristics of all patients and the treatment outcomes of 190 advanced patients who received pharmacotherapy were analyzed. Moreover, the acquired resistance mechanisms were explored based on 53 tissue or liquid re-biopsy data in 45 patients. Patients with EGFR 20ins had a shorter survival time compared with patients with non-20ins mutations. In total, 149 cases had received EGFR-tyrosine kinase inhibitors (TKI); afatinib was significantly superior to other EGFR-TKIs both in ORR and mPFS in all uncommon mutations and especially in the L861Q group. The most common acquired drug resistance mechanism was MET amplification, followed by EGFR T790M, which was significantly different from common EGFR mutations.

Clinical Outcomes of Afatinib Versus Osimertinib in Patients With Non-Small Cell Lung Cancer With Uncommon EGFR Mutations: A Pooled Analysis.

BACKGROUND: The purpose of this analysis was to investigate the effectiveness of afatinib compared to that of osimertinib in patients with non-small cell lung cancer (NSCLC) who harbored uncommon epidermal growth factor receptor (EGFR) mutations. METHODS: A PubMed database-based literature review was conducted to retrieve related studies. Patients harboring EGFR mutations besides the deletion in exon 19 (19del) and point mutation of L858R were included in this analysis. The primary outcome events were the objective response rate (ORR) and progression-free survival (PFS). Propensity score matching (PSM) at a ratio of 1:1 was used between afatinib and osimertinib groups to control the confounding factors. Uncommon EGFR mutations were categorized into 4 groups: insertion in exon 20 (ex20ins), non-ex20ins single uncommon EGFR mutations, compound EGFR mutations that with 19del or L858R, and compound EGFR mutations without 19del or L858R. RESULTS: After PSM, 71 patients in either the afatinib or osimertinib group were matched. The afatinib group had an ORR of 60.6%, slightly higher than the osimertinib group's (50.3%), the difference was not statistically significant (P = .610). However, the afatinib group showed a significantly superior PFS benefit than the osimertinib group (11.0 vs. 7.0 months, P = .044). In addition, patients harboring non-ex20ins single uncommon EGFR mutations yield the best ORR and PFS, following treatment of either afatinib (ORR: 76.7%, mPFS: 14.1 months) or osimertinib (ORR: 68.8%, mPFS: 15.1 months). Moreover, there was no significant difference in terms of ORR or PFS between the cohort of patients treated with afatinib or osimertinib, regardless of whether or not the patients had brain metastases. CONCLUSIONS: Both afatinib and osimertinib displayed favorable clinical activities toward uncommon EGFR mutations. Afatinib showed a more profound and durable PFS benefit than osimertinib, although no efficacy advantage was observed.

Efficacy and safety of dacomitinib in treatment-naïve patients with advanced NSCLC harboring uncommon EGFR mutation: an ambispective cohort study.

BACKGROUND: About 10% of non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations are harbored as uncommon mutations. This study aimed to explore the efficacy and safety of dacomitinib, a second-generation EGFR tyrosine kinase inhibitor (EGFR-TKIs), in treating uncommon EGFR-mutated advanced NSCLC. METHODS: Treatment-naïve advanced NSCLC patients treated with dacomitinib at Hunan Cancer Hospital with uncommon EGFR mutations were evaluated. The primary endpoint was progression-free survival (PFS). Secondary end points included overall survival (OS), objective response rate (ORR), disease control rate (DCR) and safety. RESULT: Between December 2019 and December 2021, a total of 16 patients was included. Median PFS was 14.0 (95% CI 4.32-23.7) months, and median OS was not reached. ORR was 68.8% (95% CI 41.3 to 89.0%) and DCR was 93.8% (95%CI 69.8 to 99.8%), including three achieving complete remission (CR) and eight achieving partial remission (PR). Median PFS for patients with brain metastasis was 9.0 (95%CI 6.9 to 11.1) months. Intracranial ORR was 100%, including 2 CR and 4 PR. Major treatment-related adverse events (TRAEs) included rash (87.5%), paronychia (62.5%), oral ulcers (50.0%), and diarrhea (50.0%), none of which were ≥ grade 3 TRAEs. CONCLUSIONS: Dacomitinib showed good activity and manageable toxicity in NSCLC patients with uncommon EGFR mutations.

Prevalence and species distribution of Candida bloodstream infection in children and adults in two teaching university hospitals in Egypt: first report of Candida kefyr.

BACKGROUND: Candidemia is a pervasive problem associated with significant morbidity and mortality in health care settings. This study aimed to determine the changing distribution of Candida species and the emergence of uncommon species. METHODS: This was a cross-sectional study performed in two Cairo University hospitals between 2019 and 2020. All Candida species isolates recovered from blood cultures of adults and pediatrics patients admitted to the hospitals were included. Candida isolates were identified by chromogenic Candida agar and Vitek2 YST identification card. Candida kefyr was confirmed by chip array. RESULTS: Candida species were responsible for 1.6% of bloodstream infections in adults and 10.8% in pediatric patients. C. albicans was the most prevalent species representing 27.8% in adults and 48.3% in pediatrics. Non-albicans species (NAC) represented the most isolated Candida species among adults and pediatrics (72.2% and 51.6%, respectively) with the predominance of C. tropicalis (27.8% and 22.5%, respectively) followed by C. parapsilosis (16.7% and 10.8%, respectively). The uncommon Candida, which is Candida species other than C. albicans, C. parapsilosis, C. tropicalis, C. glabrata, and C. krusei, represents 16.6% and 14% of all candidemia in adults and pediatrics, respectively. Only one of each of C. lusitaniae, C. utilis, and C. kefyr were detected in adults. C. lusitaniae was the most frequently recovered uncommon Candida among pediatrics resulting in 6.4% of candidemia followed by C. famata (4.3%), C. utilis (2.2%), and C. kefyr (1.1%). CONCLUSIONS: C. albicans is still the primary species isolated from pediatrics and adults with candidemia despite the considerable shift to the non-albicans species. C. tropicalis and C. parapsilosis are the most prevalent NAC. The increased prevalence of uncommon Candida species is alarming and necessitates a prompt stewardship program.

Advances in Management of the Stroke Etiology One-Percenters.

PURPOSE OF REVIEW: Uncommon causes of stroke merit specific attention; when clinicians have less common etiologies of stoke in mind, the diagnosis may come more easily. This is key, as optimal management will in many cases differs significantly from "standard" care. RECENT FINDINGS: Randomized controlled trials (RCT) on the best medical therapy in the treatment of cervical artery dissection (CeAD) have demonstrated low rates of ischemia with both antiplatelet and vitamin K antagonism. RCT evidence supports the use of anticoagulation with vitamin K antagonism in "high-risk" patients with antiphospholipid antibody syndrome (APLAS), and there is new evidence supporting the utilization of direct oral anticoagulation in malignancy-associated thrombosis. Migraine with aura has been more conclusively linked not only with increased risk of ischemic and hemorrhagic stroke, but also with cardiovascular mortality. Recent literature has surprisingly not provided support the utilization of L-arginine in the treatment of patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS); however, there is evidence at this time that support use of enzyme replacement in patients with Fabry disease. Additional triggers for reversible cerebral vasoconstriction syndrome (RCVS) have been identified, such as capsaicin. Imaging of cerebral blood vessel walls utilizing contrast-enhanced MRA is an emerging modality that may ultimately prove to be very useful in the evaluation of patients with uncommon causes of stroke. A plethora of associations between cerebrovascular disease and COVID-19 have been described. Where pertinent, authors provide additional tips and guidance. Less commonly encountered conditions with updates in diagnosis, and management along with clinical tips are reviewed.

Treatment of Non-Small Cell Lung Cancer with Atypical EGFR Mutations.

OPINION STATEMENT: EGFR tyrosine kinase inhibitors (TKI) should always be considered when treating advanced/metastatic non-small cell lung cancer (NSCLC) with atypical EGFR mutations. The first choice of TKI depends on the specific mutation(s) present and its effect on structure and function of the EGFR protein. Afatinib is the only EGFR TKI currently FDA approved for atypical EGFR mutations and has the strongest data to support its use in PACC mutations, a subgroup of atypical EGFR mutations which includes G719X and S7681. Dacomitinib may also be an option for these mutations given similar efficacy to afatinib. In contrast, for classical-like mutations such as L861Q, osimertinib should be considered the first choice given that their behavior mimics that of the classical mutations exon 19 deletion and L858R. Osimertinib should also be utilized in the setting of a concurrent T790M mutation. Superior CNS penetrance and well managed toxicity profile may also be reasons to consider osimertinib. Given that the choice of TKI may depend on the specific mutation, it is crucial that every patient diagnosed with NSCLC undergo comprehensive sequencing to identify these mutations.

Vascular anomalies: diagnostic features and step-wise approach.

The first part of this review article emphasized correct nomenclature, classification systems, and imaging algorithm of vascular anomalies. The second part of the review discusses the individual entities, highlighting the characteristic clinico-radiological features of the commonly encountered ones. A step-wise algorithmic approach is also proposed for the evaluation of a suspected case of vascular anomaly.

Overview on Therapeutic Options in Uncommon EGFR Mutant Non-Small Cell Lung Cancer (NSCLC): New Lights for an Unmet Medical Need.

The majority of epidermal growth factor receptor (EGFR) mutations (85-90%) are exon 19 deletions and L858R point mutations of exon 21, characterized by high sensitivity to EGFR-tyrosine kinase inhibitors (TKIs). Less is known about uncommon mutations (10-15% of EGFR mutations). The predominant mutation types in this category include exon 18 point mutations, exon 21 L861X, exon 20 insertions, and exon 20 S768I. This group shows a heterogeneous prevalence, partly due to different testing methods and to the presence of compound mutations, which in some cases can lead to shorter overall survival and different sensitivity to different TKIs compared to simple mutations. Additionally, EGFR-TKI sensitivity may also vary depending on the specific mutation and the tertiary structure of the protein. The best strategy remains uncertain, and the data of EGFR-TKIs efficacy are based on few prospective and some retrospective series. Newer investigational agents are still under study, and there are no other approved specific treatments targeting uncommon EGFR mutations. Defining the best treatment option for this patient population remains an unmet medical need. The objective of this review is to evaluate existing data on the outcomes, epidemiology, and clinical characteristics of lung cancer patients with rare EGFR mutations, with a focus on intracranial activity and response to immunotherapy.

The Plasma Membrane Purinoreceptor P2K1/DORN1 Is Essential in Stomatal Closure Evoked by Extracellular Diadenosine Tetraphosphate (Ap4A) in Arabidopsis thaliana.

Dinucleoside polyphosphates (NpnNs) are considered novel signalling molecules involved in the induction of plant defence mechanisms. However, NpnN signal recognition and transduction are still enigmatic. Therefore, the aim of our research was the identification of the NpnN receptor and signal transduction pathways evoked by these nucleotides. Earlier, we proved that purine and pyrimidine NpnNs differentially affect the phenylpropanoid pathway in Vitis vinifera suspension-cultured cells. Here, we report, for the first time, that both diadenosine tetraphosphate (Ap4A) and dicytidine tetraphosphate (Cp4C)-induced stomatal closure in Arabidopsis thaliana. Moreover, we showed that plasma membrane purinoreceptor P2K1/DORN1 (does not respond to nucleotide 1) is essential for Ap4A-induced stomata movements but not for Cp4C. Wild-type Col-0 and the dorn1-3 A. thaliana knockout mutant were used. Examination of the leaf epidermis dorn1-3 mutant provided evidence that P2K1/DORN1 is a part of the signal transduction pathway in stomatal closure evoked by extracellular Ap4A but not by Cp4C. Reactive oxygen species (ROS) are involved in signal transduction caused by Ap4A and Cp4C, leading to stomatal closure. Ap4A induced and Cp4C suppressed the transcriptional response in wild-type plants. Moreover, in dorn1-3 leaves, the effect of Ap4A on gene expression was impaired. The interaction between P2K1/DORN1 and Ap4A leads to changes in the transcription of signalling hubs in signal transduction pathways.

Afatinib treatment in a large real-world cohort of nonsmall cell lung cancer patients with common and uncommon epidermal growth factor receptor mutation.

The epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) afatinib improves survival in nonsmall cell lung cancer (NSCLC) patients with EGFR mutation. We analysed the outcome between EGFR mutation subtypes in a large afatinib-treated cohort in which 516 EGFR-mutated NSCLC patients receiving afatinib as front-line treatment. EGFR uncommon mutations include exon 20 insertion, de novo T790M of high or low allele frequency (dT790MHAF /dT790MLAF ), non-T790M compound mutation and others, where EGFR exon 20 insertion and dT790MHAF were defined as type-I and the rest as type-II uncommon mutation. Four hundred and sixty-one (89.3%) and 55 (10.7%) patients were common and uncommon mutation, respectively. Exon 20 insertion and dT790MHAF patients demonstrated a significantly shortened progression-free survival (PFS) (2.6 and 4.1 months) compared to EGFR common mutation, dT790MLAF and other uncommon mutation patients (15.1, 27.0 and 18.4 months; P = 3 × 10-8 ). Type-I uncommon mutation was an independent predictor of PFS (HR 4.46 [95% CI, 2.60-7.64]; P < .001) and OS (HR 2.56 [95% CI, 1.37-4.75]; P = .003). EGFR L858R patients demonstrated a significantly higher CNS progression (cause-specific HR, 3.16; 95% CI 1.24-8.08; P = .016), and type-I uncommon mutation patients exhibited a significantly higher systemic progression (cause-specific HR, 4.95; 95% CI 2.30-10.60; P = 4.3 × 10-5 ). Tendencies of higher CNS and lower systemic progression were observed in type-II uncommon mutation patients. A PFS ≥ 12 months (OR 2.38 [95% CI, 1.18-4.89]; P = .016) and uncommon EGFR mutation (OR 0.08 [95% CI, 0.01-0.48]; P = .021) were independent predictors of secondary T790M. Afatinib-treated NSCLC patients presented an EGFR genotype-specific pattern of disease progression and outcome.

Efficacy and potential resistance mechanisms of afatinib in advanced non-small cell lung cancer patients with EGFR G719X/L861Q/S768I.

BACKGROUND: Afatinib is the only currently approved EGFR-tyrosine kinase inhibitors for advanced non-small cell lung cancer (NSCLC) patients with EGFR G719X/L861Q/S768I. However, there are limited real-world data concerning the benefits and resistance mechanisms of afatinib in patients with these nonclassical mutations. To fill this gap, the present study was conducted. METHODS: All NSCLC patients treated with afatinib were screened, and patients with EGFR G719X/L861Q/S768I were enrolled into the analysis. Either tumor tissue or blood specimens were detected by the commercial next-generation sequencing (NGS) panels or amplification-refractory mutation system (ARMS)-polymerase chain reaction (PCR) to figure out the mutation genotype. RESULTS: A total of 106 advanced NSCLC patients with EGFR G719X/L861Q/S768I received afatinib treatment. The benefits of afatinib exhibited heterogeneity in different mutation genotypes. Notably, at baseline, NGS testing was performed in 59 patients, and TP53 was the most frequently coexisting mutation. Patients with TP53 mutations obtained fewer survival benefits than those with TP53 wild-type. A total of 68 patients ultimately experienced progression, and 27 patients received NGS testing to clarify the potential resistance mechanisms. EGFR-T790M, CDK4 amplification, FGFR1 amplification, PIK3CA, MET amplification, RET fusions, HER2, and BRAF mutations were identified in three (11.1%), three (11.1%), three (11.1%), three (11.1%), three (11.1%), one (3.7%), one (3.7%), and one (3.7%) of the cases, respectively. Five patients underwent ARMS-PCR testing for detecting EGFR-T790M mutation, and only one patient was T790M-positive. CONCLUSIONS: The present study elucidated the differential benefits of afatinib within different mutation genotypes and first revealed the spectrum of potential resistance mechanisms in patients with EGFR G719X/L861Q/S768I. The results of this study may provide practical clinical information that can guide optimal treatment in this setting.

Tyrosine Kinase Inhibitor Activity in Patients with NSCLC Harboring Uncommon EGFR Mutations: A Retrospective International Cohort Study (UpSwinG).

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are standard of care for patients with EGFR mutation-positive non-small-cell lung cancer (NSCLC) with common mutations (Del19 or L858R); however, 7%-23% of NSCLC tumors harbor uncommon EGFR mutations. These mutations are highly heterogeneous, and developments in detection techniques are helping to identify mutations with little or no clinical data. PATIENTS AND METHODS: In this retrospective, global, multi-center study (NCT04179890), existing health records were identified for consecutive EGFR TKI-naïve patients with uncommon EGFR mutations (T790M, ex20ins, major uncommon [G719X, L861Q, or S768I], or "other" mutations; compound mutations) treated with erlotinib, gefitinib, afatinib, or osimertinib in first or second line. Endpoints included time-to-treatment failure (TTF), objective response rate (ORR), and overall survival (OS). RESULTS: Overall, 246 patients (median age: 69.5 years; Asian: 84%) were included from 9 countries. Most patients (92%) received an EGFR TKI as first-line therapy; 54%, 43% and 3% received afatinib, first-generation TKIs, and osimertinib, respectively. Median TTF and OS with EGFR TKIs were 9.9 and 24.4 months; ORR was 43%. In patients treated with first-line chemotherapy (n = 20), median TTF and ORR were 6.6 months and 41%. Outcomes were most favorable in patients with major uncommon or compound mutations. Overall, TTF was 11.3 months with afatinib and 8.8 months with first-generation EGFR TKIs across mutation categories. In most mutation categories, median OS was >2 years. CONCLUSION: In a real-world setting, EGFR TKIs were the preferred treatment option in patients with uncommon EGFR mutations; strongest outcomes were seen in patients with major uncommon and compound mutations.

Long-term response in a patient with adenocarcinoma harboring both common and uncommon EGFR mutations.

Recently, we read a paper "Dacomitinib overcomes afatinib-refractory carcinomatous meningitis in a lung cancer patient harbouring EGFR Ex.19 deletion and G724S mutation" published in Investigational New Drugs. Their patient had a very rare compound EGFR mutation. To share our experience, we present a case of 58-year-old man with a long-term response to afatinib in a patient with previously unreported compound EGFR mutation. In patients with rare compound EGFR mutations, afatinib might be one of the treatment option.

Estimated sensitivity profiles of lung cancer specific uncommon BRAF mutants towards experimental and clinically approved kinase inhibitors.

Current experimental and clinical data are inadequate to conclusively predict the oncogenicity of uncommon BRAF mutants and their sensitivity towards kinase inhibitors. Therefore, the present study aims at estimating sensitivity profiles of uncommon lung cancer specific BRAF mutations towards clinically approved as well as experimental therapeutics based on computationally derived direct binding energies. Based on the data derived from cBioportal, BRAF mutants displayed significant mutual exclusivity with KRAS and EGFR mutants indicating them as potential drivers in lung cancer. Predicted sensitivity of BRAF-V600E conformed to published experimental and clinical data thus validating the usefulness of computational approach. The BRAF-V600K displayed higher sensitivity to most inhibitors as compared to that of the BRAF-V600E. All the uncommon mutants displayed higher sensitivity than both the wild type and BRAF-V600E towards PLX 8394 and LSN3074753. While V600K, G469R and N581S displayed favorable sensitivity profiles to most inhibitors, V600L/M, G466A/E/V and G469A/V displayed resistance profiles to a variable degree. Notably, molecular dynamic (MD) simulation revealed that increased number of interactions caused enhanced sensitivity of G469R and N581S towards sorafenib. RAF kinase inhibitors were further classified into two groups as per their selectivity (Group I: BRAF-V600E-selective and Group II: CRAF-selective) based on which potential mutation-wise combinations of RAF kinase inhibitors were proposed to overcome resistance. Based on computational inhibitor sensitivity profiles, appropriate treatment strategies may be devised to prevent or overcome secondary drug resistance in lung cancer patients with uncommon mutations.

Rationale and design of a phase II trial of dacomitinib in advanced non-small cell lung cancer patients with uncommon epidermal growth factor receptor mutations: a prospective and single arm study (DANCE study).

BACKGROUND: Dacomitinib is a second-generation, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). ARCHER-1050 showed that this agent can improve progression-free survival and overall survival in advanced non-small cell lung cancer patients with sensitive EGFR mutation compared to gefitinib. However, it is unclear whether dacomitinib is effective in patients with sensitizing uncommon EGFR mutations in exon 18-21. The aim of this study is to investigate the safety and efficacy of dacomitinib in these patients. METHODS: This is a single arm, prospective, open label and phase II trial. Sample size will be calculated by a minimax two-stage design method based on the following parameters: α = 0.075, 1-ß = 0.9, P0 = 0.20, P1 = 0.45 and a dropout rate of 10%. A total of 30 eligible patients will be included. Patients will receive continuous oral therapy with dacomitinib (45 mg/day) until disease progression, withdrawal of consent, or unacceptable toxicity, whichever occurs first. The primary endpoint is objective response rate (ORR) per RECIST version 1.1, as assessed by investigators' review. The second endpoint is disease control rate (DCR), PFS, OS, and safety. DISCUSSION: We conduct a single arm, phase II study to investigate the safety and efficacy of dacomitinib in advanced NSCLC patients with sensitizing uncommon EGFR mutations. The results of the DANCE study will provide new data regarding efficacy and safety of these patients. TRIAL REGISTRATION: NCT04504071.