Combination immunohistochemistry for CK5/6, p63, GATA6, and HNF4a predicts clinical outcome in treatment-naïve pancreatic ductal adenocarcinoma.

Although sequence-based studies show that basal-like features lead to worse prognosis and chemotherapy-resistance compared to the classical subtype in advanced pancreatic ductal adenocarcinoma (PDAC), a surrogate biomarker distinguishing between these subtypes in routine diagnostic practice remains to be identified. We aimed to evaluate the utility of immunohistochemistry (IHC) expression subtypes generated by unsupervised hierarchical clustering based on staining scores of four markers (CK5/6, p63, GATA6, HNF4a) applied to endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB) materials. EUS-FNAB materials taken from 190 treatment-naïve advanced PDAC patients were analyzed, and three IHC patterns were established (Classical, Transitional, and Basal-like pattern). Basal-like pattern (high co-expression of CK5/6 and p63 with low expression of GATA6 and HNF4a) was significantly associated with squamous differentiation histology (p < 0.001) and demonstrated the worst overall survival among our cohort (p = 0.004). IHC expression subtype (Transitional, Basal vs Classical) was an independent poor prognosticator in multivariate analysis [HR 1.58 (95% CI 1.01-2.38), p = 0.047]. Furthermore, CK5/6 expression was an independent poor prognostic factor in histological glandular type PDAC [HR 2.82 (95% CI 1.31-6.08), p = 0.008]. Our results suggest that IHC expression patterns successfully predict molecular features indicative of the Basal-like subgroup in advanced PDAC. These results provide the basis for appropriate stratification for therapeutic selection and prognostic estimation of advanced PDAC in a simplified manner.

Decoding the DNA methylome of central nervous system tumors: An emerging modality for integrated diagnosis.

The definitive diagnosis and classification of individual cancers are crucial for patient care and cancer research. To achieve a robust diagnosis of central nervous system (CNS) tumors, a genotype-phenotype integrated diagnostic approach was introduced in recent versions of the World Health Organization classification, followed by the incorporation of a genome-wide DNA methylome-based classification. Microarray-based platforms are widely used to obtain DNA methylome data, and the German Cancer Research Center (Deutsches Krebsforschungszentrum [DKFZ]) has a webtool for a DNA methylation-based classifier (DKFZ classifier). Integration of DNA methylome will further enhance the precision of CNS tumor classification, especially in diagnostically challenging cases. However, in the clinical application of DNA methylome-based classification, challenges related to data interpretation persist, in addition to technical caveats, regulations, and limited accessibility. Dimensionality reduction (DMR) can complement integrated diagnosis by visualizing a profile and comparing it with other known samples. Therefore, DNA methylome-based classification is a highly useful research tool for auxiliary analysis in challenging diagnostic and rare disease cases, and for establishing novel tumor concepts. Decoding the DNA methylome, especially by DMR in addition to DKFZ classifier, emphasizes the capability of grasping the fundamental biological principles that provide new perspectives on CNS tumors.

Epstein-Barr virus-positive monoclonal lymphoplasmacytic proliferation associated with neurosyphilis in an immunocompetent patient: A case report.

Syphilis is an infectious disease caused by the spirochete bacterium Treponema pallidum. Neurosyphilis results from the infection of the nervous system with Treponema pallidum, which can occur at any stage of syphilis. Neurosyphilis is often overlooked because of its rarity. Early-stage neurosyphilis with brain mass formation is rare. We present a case of early-stage neurosyphilis with prominent Epstein-Barr virus (EBV)-positive monoclonal lymphoplasmacytic proliferation in an immunocompetent patient. A 36-year-old man presented with a chief complaint of a progressively worsening headache, a newly developed skin rash, and a fever. Magnetic resonance imaging showed a mass lesion, which measured 18 mm in diameter, in the left frontal lobe of the cerebrum. The patient underwent an emergency operation to remove the abscess. A pathological investigation revealed complex findings. There was an abscess in the cerebrum. Lymphoplasmacytic meningitis was also noted. In addition, a vaguely nodular lesion, which was composed of plasmacytoid and lymphoid cells, was observed around the abscess. Immunohistochemically, an anti-Treponema pallidum antibody revealed numerous Treponemas around the abscess. In situ hybridization revealed that the plasmacytoid and lymphoid cells were Epstein-Barr encoding region (EBER)-positive; κ-positive cells were significantly more prevalent than λ-positive cells, suggesting light-chain restriction. Postoperatively, parenteral antibiotics were administered for four weeks. The patient has been free of recurrence for two years since the surgery. No association between neurosyphilis and EBV-positive lymphoplasmacytic proliferation has ever been reported. Mass formation in early-stage neurosyphilis is an exceptionally rare event. The present case indicates that in syphilis patients, lymphoproliferative disorders that lead to mass formation may be caused by concomitant EBV reactivation. Furthermore, when treating patients with mass lesions of the central nervous system, it is important to check their medical history and perform laboratory screening for infectious diseases to avoid overlooking syphilis infections.

RAS Family Gene Mutations, Clinicopathological Features, and Spread Patterns of Inverted Urothelial Papilloma of the Bladder.

Inverted urothelial papilloma (IUP) is a benign neoplasm characterized by a downgrowth of the urothelium beneath the surface of morphologically normal urothelial cells; however, the molecular features of IUP and their association with clinicopathological characteristics are unclear. In this study, we aimed to investigate the mutational landscape, clinicopathological features, genotype-phenotype associations, and spread patterns of IUP. We performed targeted next-generation sequencing of 39 consecutive IUP cases, the largest series investigated to date, and identified oncogenic driver mutations in RAS family genes in 34 cases (87%). HRAS mutations were the most prevalent (28 cases), which included Q61R (15 cases), followed by KRAS (5 cases) and NRAS (1 case) mutations. Characteristic mutations observed in urothelial carcinoma, including those in FGFR3 , TP53 , or the TERT promoter, were absent. HRAS -mutated IUPs were associated with a history of smoking ( P = 0.017) and streaming morphology ( P < 0.001), corresponding to the trabecular subtype. In contrast, all KRAS -mutated IUPs occurred in never-smoking patients ( P = 0.001) and showed cystic changes in morphology ( P = 0.005), corresponding to the glandular subtype. RAS Q61R immunohistochemistry visually revealed the neoplastic nature of the overlying cells and distinct spread patterns of IUP cells within the surface, including pseudoinfiltrative spread. No recurrence or carcinoma development was observed in any of the IUP cases during the follow-up period. Thus, we confirmed the importance of RAS pathway activation in IUP pathogenesis, an association between RAS family gene mutations and IUP subtypes, and the spread patterns of IUP cells within the surface.

Immuno-genomic analysis reveals eosinophilic feature and favorable prognosis of female non-smoking esophageal squamous cell carcinomas.

Most of esophageal squamous cell carcinoma (ESCC) develop in smoking males in Japan, but the genomic etiology and immunological characteristics of rare non-smoking female ECSS remain unclear. To elucidate the genomic and immunological features of ESCC in non-smoking females, we analyzed whole-genome or transcriptome sequencing data from 94 ESCCs, including 20 rare non-smoking female cases. In addition, 31,611 immune cells were extracted from four ESCC tissues and subject to single-cell RNA-seq. We compared their immuno-genomic and microbiome profiles between non-smoking female and smoking ESCCs. Non-smoking females showed much better prognosis. Whole-genome sequencing analysis showed no significant differences in driver genes or copy number alterations depending on smoking status. The mutational signatures specifically observed in non-smoking females ESCC could be attributed to aging. Immune profiling from RNA-seq revealed that ESCC in non-smoking females had high tumor microenvironment signatures and a high abundance of eosinophils with a favorable prognosis. Single-cell RNA-sequencing of intratumor immune cells revealed gender differences of eosinophils and their activation in female cases. ESCCs in non-smoking females have age-related mutational signatures and gender-specific tumor immune environment with eosinophils, which is likely to contribute to their favorable prognosis.

Endoscopic Treatment of Colo-Colonic Intussusception in a Patient with Peutz-Jeghers Syndrome.

A 19-year-old man with a history of Peutz-Jeghers syndrome (PJS) and two previous partial small bowel resections because of intussusception presented with lower abdominal pain. Computed tomography (CT) showed concentric multilayer and cord-like structures in the transverse colon. Colo-colonic intussusception was suspected and he was hospitalized. After two therapeutic enemas were unsuccessful, a colonoscopy was performed. The intussusception was reduced and a 40-mm transverse colon polyp with a thick stalk was resected. After the procedure, his abdominal pain was relieved and he was discharged on the sixth hospital day. This case and several previous reports suggest that PJS polyps with tumor diameter exceeding 30 mm and location in the transverse or sigmoid colon can cause intussusception. Endoscopic treatment should be considered for these lesions.

Pulmonary inflammatory leiomyosarcoma represents a potential diagnostic pitfall of DNA methylation-based classification of sarcomas: a case report.

BACKGROUND: Pulmonary inflammatory leiomyosarcoma (PILMS) is a rare type of myogenic tumor with prominent lymphohistiocytic infiltration. Despite their histological similarities, PILMS is immunohistochemically and genetically distinct from soft tissue inflammatory leiomyosarcoma, and its clinicopathological picture including DNA methylome data remains still unknown. CASE PRESENTATION: Here we present a case of PILMS in an 18-year-old male who underwent lobectomy. As reported previously, the current case demonstrated spindle myoid cell proliferation with smooth muscle differentiation within a prominent lymphohistiocytic infiltration and a diploid genome with a MUC3A gene alteration. DNA methylation analysis predicted this case to be an "inflammatory myofibroblastic tumor" (IMT) according to the Deutsches Krebsforschungszentrum (DKFZ) classifier. The data was analyzed by t-distributed stochastic neighbor embedding, which plotted the case tumor in the vicinity of IMT, however, there were no IMT histological features. These discordant results could be due to background non-neoplastic inflammatory cells. CONCLUSIONS: As the DNA methylation classification of PILMS might be a potential diagnostic pitfall, an integrative histological and genetic approach is required for its accurate diagnosis.

A case of low-grade intestinal-type mucinous neoplasm of the fallopian tube with KRAS exon 2 mutation.

Several types of mucinous lesions of the fallopian tube have been reported, including metaplastic and neoplastic lesions, most of which exhibit gastric phenotypes. Here, we report a unique case of a mucinous tumor arising in the right fallopian tube of a 36-year-old female who presented with refractory abdominal pain for approximately one year. Abdominal CT and MRI found a cystic lesion leading to the diagnosis of hematosalpinx, thus right salpingo-oophorectomy and appendectomy were performed. Macroscopic findings included cystic dilatation of the distal portion of the right fallopian tube, filled with gelatinous mucin. Histologically, mucinous columnar cells proliferated in papillary configurations in the cystic region without invasion, resembling low-grade appendiceal mucinous neoplasms. Immunohistochemical analysis revealed that the neoplastic cells expressed CDX-2 and SATB2, but not WT-1, PAX8, ER, PgR, or claudin 18. Sanger sequencing of the mucinous lesion identified a KRAS exon 2 mutation (p.G12A), confirming similar pathologic and genetic characteristics to ovarian mucinous borderline tumors. This rare low grade intestinal-type mucinous tumor indicates the fallopian tube epithelium can give rise to tumors resembling low-grade appendiceal mucinous neoplasms and cause pseudomyxoma peritonei without appendiceal lesions.

Increased PDGFRB and NF-κB signaling caused by highly prevalent somatic mutations in intracranial aneurysms.

Intracranial aneurysms (IAs) are a high-risk factor for life-threatening subarachnoid hemorrhage. Their etiology, however, remains mostly unknown at present. We conducted screening for sporadic somatic mutations in 65 IA tissues (54 saccular and 11 fusiform aneurysms) and paired blood samples by whole-exome and targeted deep sequencing. We identified sporadic mutations in multiple signaling genes and examined their impact on downstream signaling pathways and gene expression in vitro and an arterial dilatation model in mice in vivo. We identified 16 genes that were mutated in at least one IA case and found that these mutations were highly prevalent (92%: 60 of 65 IAs) among all IA cases examined. In particular, mutations in six genes (PDGFRB, AHNAK, OBSCN, RBM10, CACNA1E, and OR5P3), many of which are linked to NF-κB signaling, were found in both fusiform and saccular IAs at a high prevalence (43% of all IA cases examined). We found that mutant PDGFRBs constitutively activated ERK and NF-κB signaling, enhanced cell motility, and induced inflammation-related gene expression in vitro. Spatial transcriptomics also detected similar changes in vessels from patients with IA. Furthermore, virus-mediated overexpression of a mutant PDGFRB induced a fusiform-like dilatation of the basilar artery in mice, which was blocked by systemic administration of the tyrosine kinase inhibitor sunitinib. Collectively, this study reveals a high prevalence of somatic mutations in NF-κB signaling pathway-related genes in both fusiform and saccular IAs and opens a new avenue of research for developing pharmacological interventions.

Cytological characteristics of histological types of lung cancer by cytomorphometric and flow cytometric analyses using liquid-based cytology materials.

BACKGROUND: Distinguishing the histological types of lung cancer is essential for determining treatment strategies in clinical practice. In this study, cytomorphological characteristics and proliferative activities were compared among histological types of lung cancer by cytomorphometric and flow cytometric analyses using liquid-based cytology (LBC) samples. METHODS: Scraped LBC samples from 73 surgically resected specimens were collected between August 2018 and November 2019. Papanicolaou-stained and paired Ki-67-stained slides were used for cytomorphometric analyses. Another sample for each case was analyzed using a flow cytometric system (LC-1000). The cell proliferation index (CPIx) was calculated to evaluate proliferative activity. RESULTS: In total, 73 cases, including cases of adenocarcinoma (n = 53), squamous cell carcinoma (n = 14), small cell carcinoma (n = 1), large cell neuroendocrine carcinoma (NEC; n = 3), and pleomorphic carcinoma (n = 2) were evaluated. Small cell carcinoma and large cell NEC were categorized into a single group, NEC. The adenocarcinoma group tended to have a larger nuclear area and longer perimeter than other histological types. The NEC group had a considerably higher Ki-67 labeling index and significantly higher CPIx than other histological types (p = .030). A significant positive correlation was observed between the Ki-67 labeling index and CPIx for all cases (r = 0.362, p = .002). CONCLUSION: The Ki-67 labeling index and flow cytometric analyses focus on proliferative activity for the distinction of histological types of lung cancer, thereby guiding clinical decision-making.

Right Atrial Appendage Thrombus in a Patient Undergoing Thoracoscopic Left Atrial Appendectomy for Atrial Fibrillation.

Left atrial appendage (LAA) closure may prevent atrial fibrillation (AF)-induced thromboembolism. We describe a rare case of right atrial (RA) thrombus after thoracoscopic left atrial appendectomy and pulmonary vein isolation. Careful evaluation for the presence of RA thrombus in patients with persistent AF after LAA occlusion may be necessary. (Level of Difficulty: Intermediate.).

A Prospective Study of Neoadjuvant Gemcitabine Plus Nab-paclitaxel in Patients with Borderline-resectable Pancreatic Cancer.

Objectives Neoadjuvant therapy followed by radical resection improves the borderline-resectable pancreatic cancer (BRPC) prognosis; however, the optimal therapeutic regimen remains unclear. Gemcitabine plus nab-paclitaxel (GnP) showed a high anti-tumor effect in primary lesions in a prospective study for metastatic disease. However, evidence concerning its feasibility is still lacking in patients with BRPC. We therefore evaluated the tolerability of neoadjuvant GnP (NAC-GnP) for BRPC. Methods This single-center prospective study evaluated 10 patients with BRPC who were treated with two cycles of NAC-GnP. The primary endpoint was feasibility for NAC-GnP. Treatment feasibility was defined as a successful outcome in at least eight patients. Results Ten patients who had BRPC in contact with the celiac artery (n=5), superior mesenteric artery (n=3), or hepatic artery (n=2) were enrolled. The median age was 75 (range, 40-82) years old. Grade 3 anorexia and grade 2 pneumonia occurred in one patient each, so treatment was feasible in eight patients. The median primary tumor reduction and response rates were 33% (range, 0-68%) and 60%, respectively. Six of eight patients who had abnormal CA19-9 levels at the time of enrolment showed a decrease in CA19-9 levels, with a median decrease of 72%. Five patients underwent radical resection, including R0 resection in four. Postoperative grade IIIa Clavien-Dindo complications occurred in one patient (upper gastrointestinal bleeding and pancreatic fistula). Conclusion Two-cycle NAC-GnP is a feasible treatment for patients with BRPC. Further studies on NAC-GnP in patients with BRPC are warranted.