Acute onset of constrictive pericarditis due to acute myelomonocytic leukemia: A case and literature review.

We herein present a fatal case of constrictive pericarditis (CP) due to acute myelomonocytic leukemia (AMML) in a patient who initially complained of an acute onset of chest pain two days after COVID-19 vaccination. An autopsy revealed pericardial infiltration of leukemic cells. CP is rarely associated with leukemia and only 14 cases have been reported in the literature. The etiology of CP in previous reports included leukemic infiltration, graft-versus-host disease, drug-induced, post-radiation, autoimmune, and otherwise unidentified. This case indicates that leukemic infiltration can cause CP and that clinicians should include leukemia in the differential diagnosis of CP.

Evaluation of Prediabetes in Cisplatin-induced Nephrotoxicity in the Short Hydration Method: A Subgroup Analysis.

BACKGROUND/AIM: Cisplatin-induced nephrotoxicity (CIN) is one of the most attention-requiring adverse effects. We have reported that diabetes mellitus significantly increases the incidence of CIN in a short hydration method in real-world lung cancer treatment. However, the effect of prediabetes on CIN development remains unclear. This study investigated whether patients with prediabetes exhibit CIN at a greater rate during real-world cisplatin-including treatments as a subgroup analysis. PATIENTS AND METHODS: This retrospective observational study enrolled patients with lung cancer receiving cisplatin treatment (≥75 mg/m2) from May 2014 to January 2021 (n=169). Patients were divided into a prediabetes group (baseline HbA1c 5.7-6.4%) and a control group (baseline HbA1c <5.7%). The primary endpoint of this study was the incidence of CIN in all treatment cycles between the two groups. We also assessed variations in serum creatinine (SCr) levels and creatinine clearance (CCr). RESULTS: CIN occurred in 4.7% of controls and 8.3% of patients with prediabetes in all cycles, with no significant difference (p=0.37). In contrast, variation of SCr levels and CCr was significantly worse in the prediabetes group [median variation level (range) 0.11 mg/dl (-0.11-0.46 mg/dl) and 0.12 mg/dl (-0.02-1.08 mg/d) in controls and prediabetes, p=0.04 for SCr; -12.9 ml/min (-54.1-4.9 ml/min) and -16.3 ml/min (-49.4-3.0 ml/min), p=0.02 for CCr, respectively]. These results were also confirmed during the first cycle of treatment. CONCLUSION: Patients with prediabetes did not develop problematic CIN, although they exhibited significant increases in SCr and decreases in CCr.

Artemis: A Multicenter, Open-Label, Single-Arm, Phase II Study to Evaluate the Efficacy and Safety of First-Line Carboplatin/Paclitaxel/Lenvatinib/Pembrolizumab Combination for Previously Untreated Advanced or Recurrent Thymic Carcinomas.

BACKGROUND: Thymic carcinoma is a rare cancer with an aggressive clinical presentation and no organotypic symptoms. Despite using platinum-based chemotherapy as first-line treatment, the prognosis remains poor, necessitating a novel therapeutic strategy. METHODS: The artemis trial is a Phase II, single-arm, multicenter study designed to evaluate the efficacy and safety of carboplatin, paclitaxel, lenvatinib, and pembrolizumab as first-line chemotherapy for patients with advanced or recurrent thymic carcinoma. A total of 35 patients will be enrolled in this study and will receive induction therapy every 3 weeks for up to 4 cycles, followed by pembrolizumab every 3 weeks, and daily lenvatinib as maintenance therapy for up to 31 cycles (for 2 years). Lenvatinib will be continued until disease progression or unacceptable toxicity based on the discretion of the attending physician. CONCLUSION: The primary endpoint of the study is the objective response rate, with secondary endpoints including progression-free survival, overall survival, duration of response, disease control rate, and safety profile. TRIAL REGISTRATION: ClinicalTrials.gov NCT05832827 Registered on April 27, 2023, https://classic. CLINICALTRIALS: gov/ct2/show/NCT05832827. Japan Registry of Clinical Trials (jRCT), jRCT2031230114. Registered on May 22, 2023, https://jrct.niph.go.jp/latest-detail/jRCT2031230114.

Drop finger caused by lung cancer metastasis.

Skeletal muscle metastasis of lung cancer is rare. However, clinicians should be aware that tumour-induced nerve compression symptoms may develop.

Detection of factors related to treatment reduction in docetaxel and ramucirumab for non-small cell lung cancer treatment.

Treatment using docetaxel (DOC) and ramucirumab (RAM) is an effective regimen in second or later line advanced non-small cell lung carcinoma (NSCLC) treatment. However, it induces severe adverse effects, resulting in treatment reduction such as dose reduction and/or discontinuation. This study aimed to reveal the factor(s) associated with treatment reduction in DOC + RAM. We retrospectively evaluated patients with advanced NSCLC (n = 155). Treatment reduction of the second course due to severe adverse effects was conducted in 25.8% of the participants, and relative dose intensity at the second course was 95.7 ± 8.4% for DOC and 91.9 ± 24.8% for RAM. Multivariate logistic regression analyses identified that baseline anemia and prophylactic granulocyte colony-stimulating factor (G-CSF) administration are preventive factors for the reduction (adjusted odds ratio, 0.29; 95% confidence interval, 0.12-0.66; P = 0.004 for baseline anemia, 0.18; 0.08-0.42; P < 0.0001 for prophylactic G-CSF administration). The primary cause of the reduction was febrile neutropenia, and the same factors were identified. Our study revealed that patients with baseline anemia and prophylactic G-CSF administration have less risk for treatment reduction in DOC + RAM for NSCLC treatment.

Risk factor analysis for cisplatin-induced nephrotoxicity with the short hydration method in diabetic patients.

The occurrence of cisplatin (CDDP)-induced nephrotoxicity (CIN) has decreased with advancements in supportive care. In contrast, we reported that baseline diabetes mellitus (DM) complications significantly worsen CIN. This study aimed to determine further risk factors associated with CIN development in DM patients. Patients with thoracic cancer requiring DM pharmacotherapy, who received CDDP (≥ 60 mg/m2)-containing regimens using the short hydration method (n = 140), were enrolled in this retrospective multicenter observational study. The primary endpoint of the present study was the elucidation of risk factors (patient factors, DM medication influence, and treatment-related factors) associated with CIN development in patients with DM. Cisplatin-induced nephrotoxicity occurred in 22.1% of patients with DM. The median worst variation of serum creatinine levels and creatinine clearance (worst level - baseline level) was 0.16 mg/dL (range: - 0.12-1.41 mg/dL) and - 15.9 mL/min (- 85.5-24.3 mL/min), respectively. Multivariate logistic regression analyses identified female sex as the singular risk factor for CIN development in the DM population (adjusted odds ratio; 2.87, 95% confidence interval; 1.08-7.67, P = 0.04). Diabetes mellitus medication and treatment-related factors did not affect CIN development. In conclusion, our study revealed that female sex is significantly associated with CIN development in patients with DM and thoracic cancer.

Inhibition of non-homologous end joining mitigates paclitaxel resistance resulting from mitotic slippage in non-small cell lung cancer.

Mitotic slippage, which enables cancer cells to bypass cell death by transitioning from mitosis to the G1 phase without undergoing normal cytokinesis, is one likely mechanism of paclitaxel (PTX) resistance. DNA double-strand breaks (DSBs) in the G1 phase are mainly repaired through non-homologous end joining (NHEJ). Therefore, inhibiting NHEJ could augment the PTX-induced cytotoxicity by impeding the repair of PTX-induced DSBs during the G1 phase following mitotic slippage. We aimed to evaluate the effects of NHEJ inhibition on mitotic slippage after PTX treatment in non-small cell lung cancer (NSCLC). H1299, A549, H1975, and H520 NSCLC cell lines were employed. In addition, A-196 and JQ1 were used as NHEJ inhibitors. H1299 cells were PTX-resistant and exhibited an increased frequency of mitotic slippage upon PTX treatment. NHEJ inhibitors significantly augmented the PTX-induced cytotoxicity, DSBs, and apoptosis in H1299 cells. The newly generated PTX-resistant cells were even more prone to mitotic slippage following PTX treatment and susceptible to the combined therapy. Docetaxel further demonstrated synergistic effects with the NHEJ inhibitor in PTX-resistant cells. NHEJ inhibition may overcome intrinsic or acquired PTX resistance resulting from mitotic slippage by synergistically increasing the cytotoxic effects of antimitotic drugs in NSCLC.

Angiogenic inhibitor pre-administration improves the therapeutic effects of immunotherapy.

In lung cancer, immune checkpoint inhibitors (ICIs) are often inadequate for tumor growth inhibition. Angiogenic inhibitors (AIs) are required to normalize tumor vasculature for improved immune cell infiltration. However, in clinical practice, ICIs and cytotoxic antineoplastic agents are simultaneously administered with an AI when tumor vessels are abnormal. Therefore, we examined the effects of pre-administering an AI for lung cancer immunotherapy in a mouse lung cancer model. Using DC101, an anti-vascular endothelial growth factor receptor 2 (VEGFR2) monoclonal antibody, a murine subcutaneous Lewis lung cancer (LLC) model was used to determine the timing of vascular normalization. Microvessel density (MVD), pericyte coverage, tissue hypoxia, and CD8-positive cell infiltration were analyzed. The effects of an ICI and paclitaxel after DC101 pre-administration were investigated. On Day 3, increased pericyte coverage and alleviated tumor hypoxia represented the highest vascular normalization. CD8+ T-cell infiltration was also highest on Day 3. When combined with an ICI, DC101 pre-administration significantly reduced PD-L1 expression. When combined with an ICI and paclitaxel, only DC101 pre-administration significantly inhibited tumor growth, but simultaneous administration did not. AI pre-administration, and not simultaneous administration, may increase the therapeutic effects of ICIs due to improved immune cell infiltration.

A Large-Scale Prospective Concordance Study of Plasma- and Tissue-Based Next-Generation Targeted Sequencing for Advanced Non-Small Cell Lung Cancer (LC-SCRUM-Liquid).

PURPOSE: We evaluated plasma cell-free DNA (cfDNA) and tissue-based sequencing concordance for comprehensive oncogenic driver detection in non-small cell lung cancer (NSCLC) using a large-scale prospective screening cohort (LC-SCRUM-Liquid). EXPERIMENTAL DESIGN: Blood samples were prospectively collected within 4 weeks of corresponding tumor tissue sampling from patients with advanced NSCLC to investigate plasma cfDNA sequencing concordance for alterations in 8 oncogenes (EGFR, KRAS, BRAF, HER2, MET, ALK, RET, and ROS1) compared with tissue-based next-generation targeted sequencing. RESULTS: Paired blood and tissue samples were obtained in 1,062/1,112 enrolled patients with NSCLC. Oncogenic alteration was detected by plasma cfDNA sequencing and tissue assay in 455 (42.8%) and 537 (50.5%) patients, respectively. The positive percent agreement of plasma cfDNA sequencing compared with tissue DNA and RNA assays were 77% (EGFR, 78%; KRAS, 75%; BRAF, 85%; HER2, 72%) and 47% (ALK, 46%; RET, 57%; ROS1, 18%; MET, 66%), respectively. Oncogenic drivers were positive for plasma cfDNA and negative for tissue due to unsuccessful genomic analysis from poor-quality tissue samples (70%), and were negative for plasma cfDNA and positive for tissue due to low sensitivity of cfDNA analysis (61%). In patients with positive oncogenic drivers by plasma cfDNA sequencing but negative by tissue assay, the response rate of genotype-matched therapy was 85% and median progression-free survival was 12.7 months. CONCLUSIONS: Plasma cfDNA sequencing in patients with advanced NSCLC showed relatively high sensitivity for detecting gene mutations but low sensitivity for gene fusions and MET exon 14 skipping. This may be an alternative only when tissue assay is unavailable due to insufficient DNA and RNA. See related commentary by Jacobsen Skanderup et al., p. 1381.

Notch pathway regulates osimertinib drug-tolerant persistence in EGFR-mutated non-small-cell lung cancer.

Osimertinib is a third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) that has shown marked antitumor activity in patients with EGFR-mutated non-small-cell lung cancer (NSCLC). However, these effects are transient and most patients develop resistance. Reversible drug-tolerant persister (DTP) cells are defined as a small subpopulation of cells with markedly reduced sensitivity and non-genetic acquired resistance to EGFR-TKIs. Notch is a transmembrane receptor that plays an important role in tumorigenesis. We previously reported that there is significant crosstalk between the Notch and EGFR pathways in NSCLC. Moreover, the Notch pathway is associated with resistance to previous-generation EGFR-TKIs. However, the role of Notch in osimertinib resistance is not fully understood. In this study, we evaluated whether Notch is involved in osimertinib resistance. We show that NOTCH1 and Notch target genes are upregulated in osimertinib DTP cells, and that the addition of a γ-secretase inhibitor (GSI), a Notch inhibitor, impairs drug-tolerant persistence in vitro and in vivo. Compared with osimertinib, combined GSI and osimertinib suppress phospho-ERK partly by enhancing DUSP1 expression. Furthermore, Notch1 and HES1 were upregulated after EGFR-TKI treatment in half of human EGFR-mutated NSCLC tumor tissues. These results suggest that the combination of GSI and osimertinib may be a potential therapy for EGFR-mutated NSCLC.

EGFR inhibition in EGFR-mutant lung cancer cells perturbs innate immune signaling pathways in the tumor microenvironment.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) elicit potent cell cycle arrest in EGFR-mutant non-small-cell lung cancer (NSCLC) cells. However, little is known about the mechanisms through which these drugs alter the tumor phenotype that contributes to the immune escape of EGFR-mutant cells. Using EGFR-mutant NSCLC cell lines and tissue samples from patients, we investigated the changes in immune checkpoints expressed in tumor cells following EGFR inhibition. Subsequently, we also analyzed the role of soluble factors from the dying tumor cells in the activation of immune signaling pathways involved in therapy resistance. Upon EGFR-TKI treatment, we found that EGFR-mutant cells upregulated the expression of innate immune checkpoint CD24 in vitro. We then analyzed biopsy samples from six patients who developed resistance to a first-generation EGFR-TKI without the acquired T790M mutation. Immunohistochemistry revealed that levels of tumor CD24 expression were increased upon treatment compared with those from pre-treatment samples. Monocyte-derived macrophages facilitated antibody-dependent cellular phagocytosis when EGFR-TKI-treated EGFR-mutant cells were incubated with anti-CD24 antibodies in vitro, suggesting that CD24 may be a therapeutical target for EGFR-mutant lung cancer. Moreover, EGFR inhibition accelerated the release of cell-free DNA (cfDNA) from dying tumor cells, which activated the type I interferon signaling pathways in human THP-1 monocytes in a stimulator of interferon genes-dependent manner. Our study indicates that EGFR inhibition in EGFR-mutant NSCLC cells fosters a tumor microenvironment associated with immune escape. Thus, CD24 targeted therapy and cfDNA monitoring may contribute to improved treatment outcomes in patients with EGFR-mutant NSCLC.

Risk of bleeding associated with transbronchial biopsy using flexible bronchoscopy in patients with echocardiographic or chest CT evidence of pulmonary hypertension.

BACKGROUND: Endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) facilitates the diagnosis of various respiratory diseases. The safety of performing EBUS-guided TBB in patients with a finding of pulmonary hypertension (PH) is controversial. Little is known about the relationship between the risk of bleeding associated with EBUS-guided TBB in the presence of PH suspected on echocardiography or chest CT. METHODS: To assess the risk of bleeding associated with EBUS-guided TBB in patients with presumed PH per echocardiography or chest CT, we retrospectively reviewed the medical records of 314 consecutive patients who underwent EBUS-guided TBB using a guide sheath (GS), as well as echocardiography and chest CT. Bleeding complication was defined as over one minute of suctioning; repeated wedging of the bronchoscope; instillation of cold saline, diluted vasoactive substances, or thrombin due to persistent bleeding. Findings of suspected PH were defined as peak tricuspid regurgitation velocity (TRV) > 2.8 m/s on echocardiography or pulmonary artery to aorta ratio (PA:A ratio) > 0.9 on chest CT. RESULTS: In total, 35 (11.1%) patients developed bleeding, and all cases were managed safely. Furthermore, 17 (5.4%) and 59 (18.8%) patients were suspected to have PH based on echocardiography and chest CT, respectively. Among the patients suspected to have PH on echocardiography, five (5/17 = 29.4%) patients developed bleeding. Among the patients suspected to have PH on chest CT, 11 (11/59 = 18.6%) patients developed bleeding. Univariate analysis revealed that long diameter (≥ 30 mm) of the lesion, lesion location (the biopsy site was inner than the segmental bronchus), bronchoscopic diagnosis of malignancy, and additional biopsy were potential predictive factors for bleeding. The finding of suspected PH on echocardiography correlated significantly with bleeding (p = 0.03). On multivariate analysis, long diameter (≥ 30 mm) of the lesion (p = .021) and findings of suspected PH on echocardiography (p = .049) were significantly associated with bleeding. CONCLUSION: All cases of bleeding in the present study were managed safely. The risk of bleeding is moderately elevated when PH is suspected by echocardiography in patients undergoing EBUS-guided TBB using a GS.

Effects of obesity on CC16 and their potential role in overweight/obese asthma.

INTRODUCTION: Club cell secretory protein-16 (CC16) is a major anti-inflammatory protein expressed in the airway; however, the potential role of CC16 on overweight/obese asthma has not been assessed. In this study, we examined whether obesity reduces airway/circulatory CC16 levels using experimental and epidemiological studies. Then, we explored the mediatory role of CC16 in the relationship of overweight/obesity with clinical asthma measures. METHODS: Circulating CC16 levels were assessed by ELISA in three independent human populations, including two groups of healthy and general populations and asthma patients. The percentage of cells expressing club markers in obese vs. non-obese mice and human airways was determined by immunohistochemistry. A causal mediation analysis was conducted to determine whether circulatory CC16 acted as a mediator between overweight/obesity and clinical asthma measures. RESULTS: BMI was significantly and monotonously associated with reduced circulating CC16 levels in all populations. The percentage of CC16-expressing cells was reduced in the small airways of both mice and humans with obesity. Finally, mediation analysis revealed significant contributions of circulatory CC16 in the association between BMI and clinical asthma measures; 21.8% of its total effect in BMI's association with airway hyperresponsiveness of healthy subjects (p = 0.09), 26.4% with asthma severity (p = 0.030), and 23% with the required dose of inhaled corticosteroid (p = 0.042). In logistic regression analysis, 1-SD decrease in serum CC16 levels of asthma patients was associated with 87% increased odds for high dose ICS requirement (p < 0.001). CONCLUSIONS: We demonstrate that airway/circulating CC16, which is inversely associated with BMI, may mediate development and severity in overweight/obese asthma.

The CLIP1-LTK fusion is an oncogenic driver in non-small-cell lung cancer.

Lung cancer is one of the most aggressive tumour types. Targeted therapies stratified by oncogenic drivers have substantially improved therapeutic outcomes in patients with non-small-cell lung cancer (NSCLC)1. However, such oncogenic drivers are not found in 25-40% of cases of lung adenocarcinoma, the most common histological subtype of NSCLC2. Here we identify a novel fusion transcript of CLIP1 and LTK using whole-transcriptome sequencing in a multi-institutional genome screening platform (LC-SCRUM-Asia, UMIN000036871). The CLIP1-LTK fusion was present in 0.4% of NSCLCs and was mutually exclusive with other known oncogenic drivers. We show that kinase activity of the CLIP1-LTK fusion protein is constitutively activated and has transformation potential. Treatment of Ba/F3 cells expressing CLIP1-LTK with lorlatinib, an ALK inhibitor, inhibited CLIP1-LTK kinase activity, suppressed proliferation and induced apoptosis. One patient with NSCLC harbouring the CLIP1-LTK fusion showed a good clinical response to lorlatinib treatment. To our knowledge, this is the first description of LTK alterations with oncogenic activity in cancers. These results identify the CLIP1-LTK fusion as a target in NSCLC that could be treated with lorlatinib.

A phase I/II study of osimertinib in EGFR exon 20 insertion mutation-positive non-small cell lung cancer.

OBJECTIVES: Several preclinical data proposed a potential efficacy of osimertinib, a third-generation EGFR tyrosine kinase inhibitor, for EGFR exon 20 insertion (EGFR ex20ins)-positive non-small cell lung cancer (NSCLC). However, reported case series and a retrospective study proposed controversial efficacy. The efficacy of osimertinib in EGFR ex20ins-positive NSCLC have not been well evaluated in prospective clinical trials. In this study, we performed a prospective, single-arm, multi-center, open-label, non-randomized phase I/II study to evaluate efficacy of osimertinib for EGFR ex20ins-positive NSCLC. MATERIALS AND METHODS: From August 2018 to January 2020, 14 NSCLC patients with EGFR ex20ins were enrolled, of whom 2 were excluded because they did not meet the inclusion criteria. Efficacy and safety of 80 mg osimertinib were evaluated. In addition, we performed a translational exploratory study to clarify the association of mutation type-specific drug sensitivity, osimertinib pharmacokinetic data, and clinical efficacy. RESULTS: Of the evaluated patients, none experienced objective response, 7 experienced stable disease (58.3%), and 5 experienced disease progression (41.7%). The median progression free survival (PFS) was 3.8 months, and the median overall survival was 15.8 months. Interestingly, the exploratory study demonstrated statistically significant positive correlation between plasma osimertinib concentration/in vitro IC50 ratio and PFS (R = 0.9912, P = 0.0001), highlighting the mutation type-specific concentration-dependent efficacy of osimertinib for EGFR ex20ins-positive NSCLC. CONCLUSIONS: Regular dose, 80 mg/day, of osimertinib has limited clinical activity in NSCLC patients with EGFR ex20ins. The translational study proposed the potential efficacy of higher dose osimertinib in a subgroup of EGFR ex20ins-positive NSCLC.

Randomized phase II trial of uracil/tegafur and cisplatin versus pemetrexed and cisplatin with concurrent thoracic radiotherapy for locally advanced unresectable stage III non-squamous non-small cell lung cancer: NJLCG1001.

BACKGROUND: The optimal regimen for concurrent chemoradiotherapy (CCRT) of locally advanced non-squamous non-small cell lung cancer (NSCLC) was not definitive. We conducted randomized phase II study, NJLCG0601, and chemoradiotherapy with uracil/tegafur (UFT) and cisplatin achieved promising efficacy without severe toxicities. Here, we evaluated between this regimen and pemetrexed plus cisplatin in chemoradiotherapy for stage III non-squamous NSCLC. METHODS: Patients with inoperable stage III non-squamous NSCLC were randomly assigned in a 1:1 ratio to UFT 400 mg/m2 on days 1-14 and 29-42, and cisplatin 80 mg/m2 on days 8 and 36 (UP), or cisplatin 75 mg/m2 and pemetrexed 500 mg/m2 on days 1, 22, and 43 (PP). Involved-field radiotherapy (IFRT) underwent from day 1 to a total dose of 66 Gy in 33 fractions. Consolidation chemotherapy after CCRT was prohibited for this study. The primary endpoint was defined as 2-year overall survival (OS). This trial was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN000003948). RESULTS: From November 2010 to June 2017, 86 patients were entered from 11 institutions. Median follow-up was 54 months. Of the 85 eligible patients, the 2-year OS rate was 78.6% (95% CI, 62.8-88.3%) in UP and 85.5% (95% CI, 70.5-93.2%) in PP. Median PFS and OS was 12.3 and 64.2 months in UP, 26.2 months and not reached in PP, respectively. Grade 3/4 febrile neutropenia was more frequent in the UP group (14.0% vs. 2.0%). CONCLUSIONS: Both UP and PP with IFRT achieved the expected 2-year OS. PP engendered more favorable OS and PFS compared to UP in terms.

A case of radio-insensitive SMARCA4-deficient thoracic undifferentiated carcinoma with severe right heart failure.

SMARCA4-deficient thoracic sarcomatoid tumors were characterized by inactivating mutations of SMARCA4 and often found in the chest of young and middle-aged males with a smoking history. Recently, SMARCA4-deficient thoracic sarcomatoid tumors were reported to represent primarily smoking-associated undifferentiated/de-differentiated carcinomas rather than primary thoracic sarcomas. The main complication of this tumor is compression of the respiratory tract and/or blood vessels. A 39-year-old man presented with a 2-month history of fever and dyspnea. Computed tomography revealed a mediastinal tumor invading the right and left pulmonary arteries. Because of severe right heart failure, we considered him ineligible for bronchoscopy. We scheduled palliative irradiation with 40 Gy/20 Fr to improve hemodynamics and perform endobronchial ultrasound transbronchial needle aspiration later. However, irradiation was ineffective, and his general condition deteriorated quickly and he died after a 7-week hospitalization. An autopsy revealed that the diagnosis was SMARCA4-deficient thoracic undifferentiated carcinoma. It has been reported that this tumor is insensitive to radiotherapy and there were some cases which responded to an immune checkpoint inhibitor. Therefore, when caring for patients with mediastinal tumors that invade and compress the trachea and large vessels, it is important to consider this tumor as a differential diagnosis and try to make a pathological diagnosis as soon as possible.

Delta-like 1 homolog (DLK1) as a possible therapeutic target and its application to radioimmunotherapy using 125I-labelled anti-DLK1 antibody in lung cancer models (HOT1801 and FIGHT004).

OBJECTIVES: Delta-like 1 homolog (DLK1) is a non-canonical Notch ligand known to be expressed in several cancers but whose role in lung cancer is not yet fully understood. We sought to confirm DLK1 expression in small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC), and to examine DLK1's clinical significance. Furthermore, we examined the possible utility of DLK1 as a novel target in radioimmunotherapy (RIT). METHODS: We retrospectively assessed the correlation between clinical features and DLK1 expression by immunohistochemistry in resected specimens from 112 patients with SCLC and 101 patients with NSCLC. Moreover, we performed cell and animal experiments, and examined the possibility of RIT targeting DLK1 in SCLC using iodine-125 (125I) -labeled anti-DLK1 antibody, knowing that 125I can be replaced with the alpha-particle-emitter astatine-211 (211At). RESULTS: In SCLC and NSCLC, 20.5 % (23/112) and 16.8 % (17/101) of patients (respectively) had DLK1-positive tumors. In NSCLC, DLK1 expression was associated with recurrence-free survival (P < 0.01) but not with overall survival. In SCLC, there was no association between DLK1 expression and survival. In addition, 125I-labeled anti-DLK1 antibody specifically targeted DLK1 on human SCLC tumor cell lines. Furthermore, 125I-labeled anti-DLK1 antibody was incorporated into tumor tissue in a mouse model. CONCLUSION: A proportion of SCLC and NSCLC exhibits DLK1 expression. As a clinical feature, DLK1 expression could be a promising prognostic factor for recurrence in patients with resected NSCLC. In addition, DLK1 could serve as a new therapeutic target, including RIT, as suggested by our pilot study using a radiolabeled anti-DLK1 antibody in SCLC.

Immune checkpoint inhibitor-induced enteritis assessed using capsule endoscopy.

We performed capsule endoscopy for a patient with immune checkpoint inhibitor-induced enteritis and found multiple erosions or small ulcers in the small intestine. No reports demonstrated the effectiveness of capsule endoscopy for immune checkpoint inhibitor-induced gastrointestinal adverse events, and our case suggests that capsule endoscopy may be useful to evaluate immune checkpoint inhibitor-induced enteritis.

Nivolumab-induced immune thrombocytopenia in a patient with malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) is a rare and highly aggressive tumor. Nivolumab showed durable antitumor effect in patients with recurrent MPM and was approved for those patients in Japan in 2018. Immune related adverse event (irAE) is occurred in various organs and is suggestive to be related to better outcome of nivolumab. Frequency of hematological irAE is low and there are few reports about hematological irAE and association between irAE and outcome of nivolumab in patients with MPM. We present a case of recurrent MPM who responded to nivolumab treatment and experienced nivolumab-induced immune thrombocytopenia (ITP). Although high dose dexamethasone was administered and platelet count increased transiently, re-administration of dexamethasone was required to maintain normal count of platelet. The careful and intensive management of ITP treatment is necessary in cases who show no response or relapse to initial glucocorticoids treatment. This is the first report about nivolumab-induced ITP and association with response to nivolumab in MPM.