AIMS:Accurate diagnosis of lung adenocarcinoma (LUAD), particularly in small biopsy specimens, can be challenging due to limited tissue availability and the presence of histological mimickers. Claudin-18 (Cldn18), a tight junction protein with a lung-specific isoform (Cldn18.1), is normally expressed in alveolar epithelium and is implicated in maintaining alveolar integrity. Loss of Cldn18 has been linked to LUAD development through dysregulated YAP signalling. This study evaluated Cldn18 expression across lung cancer subtypes, with particular focus on LUAD. METHODS AND RESULTS:Cldn18 immunohistochemical expression was retrospectively assessed in 391 lung resection specimens and 53 small biopsy samples. Normal alveoli and reactive pneumocytes consistently expressed Cldn18, whereas LUADs, especially non-mucinous LUADs (NM-LUADs), typically showed marked loss. Complete absence of Cldn18 was observed in 83% of NM-LUAD resections and 84.8% of NM-LUAD biopsies. ROC analysis demonstrated excellent diagnostic accuracy (AUC 0.992), with sensitivity of 98.4% and specificity of 100%. Lepidic NM-LUAD components, a frequent diagnostic pitfall especially in small specimens, showed low expression in most cases (>50% of tumour cells in 24/26). Similarly, 6/7 atypical adenomatous hyperplasia (AAH) cases exhibited low expression, while all reactive pneumocyte proliferations retained staining. By contrast, mucinous LUADs (M-LUADs) preserved Cldn18 expression in 35/54 cases, providing a clear distinction from NM-LUADs with mucin production. CONCLUSIONS:Cldn18 loss is a promising diagnostic biomarker for NM-LUAD. Complete loss of Cldn18 expression could serve as an ancillary tool for distinguishing malignant lesions from NM-LUAD mimickers and for differentiating NM-LUADs with mucin production from true M-LUADs, particularly in small or challenging biopsies.

INTRODUCTION:The aim of this project is to assess interobserver agreement for programmed death-ligand 1 (PD-L1) scoring on of non-small cell lung cancer (NSCLC) on cytological specimens in a large-scale multicenter study, by exploiting the cell block-derived tissue microarray (cbTMA) approach. METHODS:A total of 65 cell blocks (CB) diagnosed as NSCLC were retrospectively collected and selected for TMA preparation. Hematoxylin-eosin and PD-L1 stained slides were digitized and uploaded on a free web sharing platform. Participants were asked to provide PD-L1 assessment by using the clinically relevant cutoff of tumor proportion score (TPS) (<1%; 1%-49%; >50%). Interobserver agreement was calculated using Fleiss's κ. RESULTS:Of 65 CBs, 11 were deemed not suitable; therefore, an overall number of 54 cores were used for the preparation of four TMAs. A total of 1674 evaluations were provided by 31 cytopathologists from 21 different institutions in nine countries. The statistical analysis showed a moderate overall agreement (κ = 0.49). The highest agreement was achieved in the TPS >50% category (κ = 0.57); moderate agreement was observed in TPS <1% category (κ = 0.51) and the lowest κ value was obtained for TPS 1%-49% category (k = 0.32). CONCLUSIONS:The overall moderate agreement observed showed that there is still room for improvement in inter-pathologist agreement for PD-L1 evaluation on cytological samples, highlighting the need for standardization in sample preparation, focused training in PD-L1 evaluation on cytological material, and the integration of machine learning tools to improve interobserver consistency.

Liver fibrosis is a major health problem worldwide and currently available treatments are only supportive. The microRNA-34 (miR-34) family is upregulated in response to chronic liver injuries, and miR-34b/c downregulates the platelet-derived growth factor signaling receptors. Mice deleted of miR-34b/c were found to be more susceptible to liver fibrosis. Adeno-associated viral (AAV) vector-mediated hepatocyte-specific expression of miR-34b/c ameliorated liver fibrosis/cirrhosis in mice. Interestingly, expression of miR-34b/c into hepatocytes inhibited hepatic stellate cell activation, although no evidence of miR-34b/c expression or transfer from hepatocytes was found into hepatic stellate cells. In conclusion, these findings support delivery of miR-34b/c as anti-fibrotic treatment and may pave the way toward the development of novel microRNA (miRNA)-based therapies against hepatic fibrosis.

Metastases to the pancreas (PM), although rare, have been increasingly identified in recent years, especially among high-volume pancreatic centers. They are often asymptomatic and incidentally detected during follow-up examinations, even several years after the treatment of the primary tumor. In this scenario, endoscopic ultrasound (EUS) has emerged as a crucial diagnostic tool for PM, being capable of providing a detailed morphological characterization and safe and effective tissue acquisition for cytohistological examination. The aim of our study was to extensively review the current evidence concerning the role of EUS in the diagnosis of PM, specifically focusing on its morphological features, contrast-enhancement patterns, and tissue acquisition techniques.

Liver fibrosis, characterized by scar tissue accumulation due to liver injury, poses significant barriers to liver-targeted gene therapy. Current clinical trials exclude patients with fibrosis, as intact liver architecture is considered essential for efficient and safe adeno-associated viral vector (AAV)-mediated gene delivery. Here, we show that liver fibrosis reduces the efficiency of hepatocyte transduction by AAV8 vectors across three mouse models with diverse fibrotic patterns. This inefficiency stems primarily from decreased vector uptake by the liver rather than loss of vector genomes due to hepatocyte turnover. Additionally, fibrosis alters blood vector clearance and redistributes AAV particles to extra-hepatic organs, such as spleen, lung, and kidney. At the cellular level, fibrosis decreases AAV genome content in hepatocytes while increasing it in non-parenchymal liver cells and splenic immune cells. Importantly, the capsid variant AAV-KP1 retains transduction efficiency in fibrotic livers, highlighting its potential for expanding gene therapy applications to fibrotic diseases.

Pancreatic ductal adenocarcinoma (PDAC), a neoplasm of the gastrointestinal tract, is the most common pancreatic malignancy (90%) and the fourth highest cause of cancer mortality worldwide. Surgery intervention is currently the only strategy able to offer an advantage in terms of overall survival, but prognosis remains poor even for operated patients. Therefore, the development of robust biomarkers for early diagnosis and prognostic stratification in clinical practice is urgently needed. In this work, we investigated deregulated microRNAs (miRNAs) in tissues from PDAC patients with high (G3) or low (G2) histological grade and with (N+) or without (N−) lymph node metastases. miRNA expression profiling was performed by a comprehensive PCR array and subsequent validation by RT-qPCR. The results showed a significant increase in miR-1-3p, miR-31-5p, and miR-205-5p expression in G3 compared to G2 patients (** p < 0.01; *** p < 0.001; *** p < 0.001). miR-518d-3p upregulation and miR-215-5p downregulation were observed in N+ compared to N− patients. A statistical analysis performed using OncomiR program showed the significant involvement (p < 0.05) of two miRNAs (miR-31 and miR-205) in the histological grade of PDAC patients. Also, an expression analysis in PDAC patients showed that miR-31 and miR-205 had the highest expression at grade 3 compared with normal and other tumor grades. Overall, survival plots confirmed that the overexpression of miR-31 and miR-205 was significantly correlated with decreased survival in TCGA PDAC clinical samples. A KEGG pathway analysis showed that all three miRNAs are involved in the regulation of multiple pathways, including the Hippo signaling, adherens junction and microRNAs in cancer, along with several target genes. Based on in silico analysis and experimental validation, our study suggests the potential role of miR-1-3p, miR-31-5p, and miR-205-5p as useful clinical biomarkers and putative therapeutic targets in PDAC, which should be further investigated to determine the specific molecular processes affected by their aberrant expression.

Pancreatic cystic lesions (PCLs) have been increasingly identified in recent years, encompassing a wide spectrum ranging from benign non-evolutive to malignant invasive lesions. Despite various clinical, laboratory, imaging, endoscopic ultrasound, and cytohistological features that may aid clinicians in the complex differential diagnosis of PCLs, only a few pathognomic signs distinctive to specific PCLs have been identified. Although rarely encountered, their proper recognition is crucial for the appropriate management of PCLs. The aim of our review is to extensively discuss and illustrate pathognomic signs in the setting of PCLs.

Thymic epithelial tumors (TETs) are rare malignant neoplasms arising in the thymus gland. Nevertheless, TETs, including thymomas (TMs), thymic carcinomas (TCs), and thymic neuroendocrine neoplasms (TNENs), are the most common mediastinal malignancies overall. A multidisciplinary approach is required for the appropriate diagnostic and therapeutic management of TETs. To date, the main therapeutic strategies are largely depended on the stage of the tumor and they include surgery with or without neoadjuvant or adjuvant therapy, represented by platinum-based chemotherapy, radiotherapy or chemoradiotherapy. Immune checkpoint inhibitors (ICIs) are ongoing under evaluation in the advanced or metastatic diseases despite the challenges related to the very low tumor mutation burden (TMB) and the high incidence of immune-related adverse events in TETs. In this regard, predictive impact of tissue biomarkers expression such as programmed cell death ligand-1 (PD-L1), and other emerging biomarkers, as well as their optimal and shared interpretation are currently under evaluation in order to predict response rates to ICIs in TETs.

Primary malignant brain tumours are more than one-third of all brain tumours and despite the molecular investigation to identify cancer driver mutations, the current therapeutic options available are challenging due to high intratumour heterogeneity. In addition, an immunosuppressive and inflammatory tumour microenvironment strengthens cancer progression. Therefore, we defined an immune and inflammatory profiling of meningioma and glial tumours to elucidate the role of the immune infiltration in these cancer types. Using tissue microarrays of 158 brain tumour samples, we assessed CD3, CD4, CD8, CD20, CD138, Granzyme B (GzmB), 5-Lipoxygenase (5-LOX), Programmed Death-Ligand 1 (PD-L1), O-6-Methylguanine-DNA Methyltransferase (MGMT) and Transglutaminase 2 (TG2) expression by immunohistochemistry (IHC). IHC results were correlated using a Spearman correlation matrix. Transcript expression, correlation, and overall survival (OS) analyses were evaluated using public datasets available on GEPIA2 in Glioblastoma (GBM) and Lower Grade Glioma (LGG) cohorts. Seven out of ten markers showed a significantly different IHC expression in at least one of the evaluated cohorts whereas CD3, CD4 and 5-LOX were differentially expressed between GBMs and astrocytomas. Correlation matrix analysis revealed that 5-LOX and GzmB expression were associated in both meningiomas and GBMs, whereas 5-LOX expression was significantly and positively correlated to TG2 in both meningioma and astrocytoma cohorts. These findings were confirmed with the correlation analysis of TCGA-GBM and LGG datasets. Profiling of mRNA levels indicated a significant increase in CD3 (CD3D, CD3E), and CD138 (SDC1) expression in GBM compared to control tissues. CD4 and 5-LOX (ALOX5) mRNA levels were significantly more expressed in tumour samples than in normal tissues in both GBM and LGG. In GBM cohort, GzmB (GZMB), SDC1 and MGMT gene expression predicted a poor overall survival (OS). Moreover, in LGG cohort, an increased expression of CD3 (CD3D, CD3E, CD3G), CD8 (CD8A), GZMB, CD20 (MS4A1), SDC1, PD-L1, ALOX5, and TG2 (TGM2) genes was associated with worse OS. Our data have revealed that there is a positive and significant correlation between the expression of 5-LOX and GzmB, both at RNA and protein level. Further evaluation is needed to understand the interplay of 5-LOX and immune infiltration in glioma progression.

Objective. ALK, ROS1, NTRK, and RET gene fusions and MET exon 14 skipping alterations represent fundamental predictive biomarkers for advanced non-small cell lung cancer (NSCLC) patients to ensure the best treatment choice. In this scenario, RNA-based NGS approach has emerged as an extremely useful tool for detecting these alterations. In this study, we report our NGS molecular records on ALK, ROS1, NTRK, and RET gene fusions and MET exon 14 skipping alterations detected by using a narrow RNA-based NGS panel, namely SiRe fusion. Methods. We retrospectively reviewed data on 201 advanced stage NSCLC patients who were referred to our laboratory for RNA-based molecular evaluation of ALK, ROS1, RET, NTRK gene rearrangements as well as MET exon 14 skipping. Results. Overall, 23 (11.4%) positive cases were retrieved. Regarding molecular assessment, 11 (5.5%), 2 (1.0%), 9 (4.5%), and 1 (0.5%) out of 201 harbored an ALK, ROS1, RET gene rearrangement, or MET exon 14 skipping, respectively. Conclusions. In this study, we provide real-world experience on RNA-based NGS analysis in patients with advanced stage NSCLC.

Application of classic liver-directed gene replacement strategies is limited in genetic diseases characterized by liver injury due to hepatocyte proliferation, resulting in decline of therapeutic transgene expression and potential genotoxic risk. Wilson disease (WD) is a life-threatening autosomal disorder of copper homeostasis caused by pathogenic variants in copper transporter ATP7B and characterized by toxic copper accumulation, resulting in severe liver and brain diseases. Genome editing holds promise for the treatment of WD; nevertheless, to rescue copper homeostasis, ATP7B function must be restored in at least 25% of the hepatocytes, which surpasses by far genome-editing correction rates. We applied a liver-directed, nuclease-free genome editing approach, based on adeno-associated viral vector-mediated (AAV-mediated) targeted integration of a promoterless mini-ATP7B cDNA into the albumin (Alb) locus. Administration of AAV-Alb- mini-ATP7B in 2 WD mouse models resulted in extensive liver repopulation by genome-edited hepatocytes holding a proliferative advantage over nonedited ones, and ameliorated liver injury and copper metabolism. Furthermore, combination of genome editing with a copper chelator, currently used for WD treatment, achieved greater disease improvement compared with chelation therapy alone. Nuclease-free genome editing provided therapeutic efficacy and may represent a safer and longer-lasting alternative to classic gene replacement strategies for WD.

BACKGROUND/AIM:Lung cancer is one of the most common malignant neoplastic diseases and by far the leading cause of cancer death worldwide. Recently, immune checkpoint inhibitors (ICIs) have received increasing attention for playing a crucial role in non-small cell lung cancer (NSCLC). Biomarkers, such as programmed cell death-ligand 1 (PD-L1) and tumor mutational burden (TMB), seemed to be helpful in selecting patients who are more likely to benefit from ICI treatment: however, their role has not yet been fully clarified.PATIENTS AND METHODS:In this retrospective study, we evaluated the relationship between pre-treatment peripheral blood neutrophil-to-lymphocyte ratio (NLR) and survival in 252 patients suffering from advanced NSCLC who had received pembrolizumab as their first-line immunotherapy.RESULTS:Compared to their NLR low counterparts who had a median overall survival (OS) of 34.8 months, patients with NLRs above 4.8 had a median OS of 7.6 months (HR=3.26, 95%Cl=2.3-4.6, p-value<0.0000001). In multivariate Cox regression analysis, alongside other variables, such as metastatic sites, age, and sex, NLR and PD-L1 predicted progression-free survival and OS; furthermore, a very high NLR - over 10 - seemed to forecast a very dismal prognosis in patients undergoing immunotherapy, with sudden deaths in the days immediately following therapy (median OS=3.8 months).CONCLUSION:NLR acts as a valuable and reliable prognostic factor in non-small cell lung carcinoma patients undergoing first line immunotherapy with pembrolizumab. Additional investigation is necessary to fully elucidate the underlying biological rationale, which can be found in myeloid derived suppressor cells, a heterogeneous population of cells with neutrophil-like immunophenotypic features.

Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common gastroenterological emergency associated with significant morbidity and mortality. Gastroenterologists and other involved clinicians are generally assisted by international guidelines in its management. However, NVUGIB due to peptic ulcer disease only is mainly addressed by current guidelines, with upper gastrointestinal endoscopy being recommended as the gold standard modality for both diagnosis and treatment. Conversely, the management of rare and extraordinary rare causes of NVUGIB is not covered by current guidelines. Given they are frequently life-threatening conditions, all the involved clinicians, that is emergency physicians, diagnostic and interventional radiologists, surgeons, in addition obviously to gastroenterologists, should be aware of and familiar with their management. Indeed, they typically require a prompt diagnosis and treatment, engaging a dedicated, patient-tailored, multidisciplinary team approach. The aim of our review was to extensively summarize the current evidence with regard to the management of rare and extraordinary rare causes of NVUGIB.

IntroductionAn accurate histological evaluation of invasive lung adenocarcinoma is essential for a correct clinical and pathological definition of the tumour. Different grading systems have been proposed to predict the prognosis of invasive lung adenocarcinoma.Areas coveredInvasive non mucinous lung adenocarcinoma is often morphologically heterogeneous, consisting of complex combinations of architectural patterns with different proportions. Several grading systems for non-mucinous lung adenocarcinoma have been proposed, being the main based on architectural differentiation and the predominant growth pattern. Herein we perform a thorough review of the literature using PubMed, Scopus and Web of Science and we highlight the peculiarities and the differences between the main grading systems and compare the data about their prognostic value. In addition, we carried out an evaluation of the proposed grading systems for less common histological variants of lung adenocarcinoma, such as fetal adenocarcinoma and invasive mucinous adenocarcinoma.Expert opinionThe current IASLC grading system, based on the combined score of predominant growth pattern plus high-grade histological pattern, shows the stronger prognostic significance than the previous grading systems in invasive non mucinous lung adenocarcinoma.

Background: Large Cell Neuroendocrine Carcinoma (LCNEC) is a rare subtype of lung cancer with poor clinical outcomes. Data on recurrence-free survival (RFS) in early and locally advanced pure LCNEC after complete resection (R0) are lacking. This study aims to evaluate clinical outcomes in this subgroup of patients and to identify potential prognostic markers. Methods: Retrospective multicenter study including patients with pure LCNEC stage I-III and R0 resection. Clinicopathological characteristics, RFS, and disease-specific survival (DSS) were evaluated. Univariate and multivariate analyses were performed. Results: 39 patients (M:F = 26:13), with a median age of 64 years (44–83), were included. Lobectomy (69.2%), bilobectomy (5.1%), pneumonectomy (18%), and wedge resection (7.7%) were performed mostly associated with lymphadenectomy. Adjuvant therapy included platinum-based chemotherapy and/or radiotherapy in 58.9% of cases. After a median follow-up of 44 (4–169) months, the median RFS was 39 months with 1-, 2- and 5-year RFS rates of 60.0%, 54.6%, and 44.9%, respectively. Median DSS was 72 months with a 1-, 2- and 5-year rate of 86.8, 75.9, and 57.4%, respectively. At multivariate analysis, age (cut-off 65 years old) and pN status were independent prognostic factors for both RFS (HR = 4.19, 95%CI = 1.46–12.07, p = 0.008 and HR = 13.56, 95%CI 2.45–74.89, p = 0.003, respectively) and DSS (HR = 9.30, 95%CI 2.23–38.83, p = 0.002 and HR = 11.88, 95%CI 2.28–61.84, p = 0.003, respectively). Conclusion: After R0 resection of LCNEC, half of the patients recurred mostly within the first two years of follow-up. Age and lymph node metastasis could help to stratify patients for adjuvant therapy.

The global coronavirus 2019 (COVID-19) pandemic required vaccination even in children to reduce infection. We report on the development of acute kidney injury (AKI) and minimal change disease (MCD) nephrotic syndrome (NS), shortly after the first injection BNT162b2 COVID-19 vaccine (Pfizer-BioNTech). A 12-year-old previously healthy boy was referred to our hospital with complaints of peripheral edema and nephrotic range proteinuria. Nine days earlier he had received his first injection BNT162b2 COVID-19 vaccine (Pfizer-BioNTech). Seven days after injection, he developed leg edema, which rapidly progressed to anasarca with significant weight gain. On admission, serum creatinine was 1.3 mg/dL and 24-hour urinary protein excretion was 4 grams with fluid overload. As kidney function continued to decline over the next days, empirical steroid treatment and renal replacement therapy with ultrafiltration were started and kidney biopsy was performed. Seven days after steroid therapy, kidney function began to improve, gradually returning to normal. The association of MCD, nephrotic syndrome and AKI hasn't been previously described following the Pfizer-BioNTech COVID-19 vaccine in pediatric population, but this triad has been reported in adults. We need further similar case reports to establish the real incidence of this possible vaccine side effect.

Drug-induced acute pancreatitis (DIP) is a recognised but underreported entity in the literature. Immunotherapy drugs have been described as one possible emerging cause, although the pathogenic mechanism is still largely unclear. To date, only a few cases have been reported, even if in recent times there is an over-increasing awareness of this pathologic entity. The imaging-based diagnosis of DIP can be difficult to establish, representing a real challenge for a radiologist, especially when the inflammatory disease appears as a focal mass suspicious for a malignancy. Case report: We herein report the case of a 71-year-old man with a known history of partially responsive lung adenocarcinoma subtype with high programmed cell death ligand 1 (PD-L1) expression, who underwent positron emission tomography (PET)/computed tomography (CT) imaging follow-up after one year of immunotherapy. The exam revealed a stocky/packed lesion in the pancreatic body, with increased 18F-fluorodeoxyglucose (FDG) accumulation highly suggestive of pancreatic cancer, which finally was proven to be a DIP induced by immunotherapy. Conclusion: Distinguishing between focal DIP and pancreatic neoplasm is, therefore, crucial for timely therapeutic management and prognostic stratification. A deep knowledge of possible imaging pitfalls coupled with a comprehensive clinical and laboratory assessment is pivotal to avoid any delays in diagnosis.