Interobserver agreement of pathologic classification and grading of tumoral intraductal pre-invasive neoplasms of the bile duct.

Current WHO terminology and recent publications have classified tumoral (grossly visible) intraductal pre-invasive neoplasms of bile duct (TIDN) into three categories: intraductal papillary neoplasm of bile duct (IPNB), intraductal papillary oncocytic neoplasm (IOPN), and intraductal tubulopapillary neoplasm (ITPN). A total of 227 cases of TIDN and related lesions ≥3 mm in height were examined by 10 biliary pathologists referring to these 3 categories and two pathologic gradings: two-tiered system (low- and high-grade dysplasia) and modified types 1 and 2 subclassification. Among them, IPNB was the most frequent (183 cases), followed by IOPN (28 cases), while ITPN was rare (2 cases), and interobserver agreement in this classification was "substantial" (κ-value, 0.657). The interobserver agreement of two-tiered grading system of TIDN was "slight" (κ-value, 0.201), while that of modified types 1 and 2 subclassification was "moderate" (κ-value, 0.515), and 42 % were of type 1, and 58 % were of type 2. Type 1 TIDN showed occasional stromal invasion (6.7 %), whereas type 2 TIDN was frequently associated with stromal invasion (49.6 %) (p < 0.01). In conclusion, the classification of TIDN into three categories and modified types 1 and 2 subclassification are a practically applicable classification and grading system for TIDN.

Effectiveness of radiation therapy on brain invasion by human papillomavirus-related multiphenotypic sinonasal carcinoma: A case report.

Human papillomavirus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC) is newly suggested and characterized by HPV-related tumors. HMSC has a relatively good prognosis. No cases of brain invasion have been reported to date. We encountered a case of brain invasion by HMSC, in which we assessed the effectiveness of radiotherapy in comparison with biopsy and autopsy. A 69-year-old man was referred to a hospital three months after intracerebral hemorrhage (ICH). Contrast magnetic resonance imaging revealed a tumor in the ethmoid sinus involving the brain. We performed transnasal biopsy and intensity-modulated radiotherapy for sinonasal and intracranial lesions. Despite radiotherapy, the patient died on day 41 after radiation. Biopsy specimens displayed mixed findings of epithelial and mesenchymal components. The tumor was immunoreactive for p16, and the RNA in situ hybridization for HPV was positive. Finally, we diagnosed the patient as having HMSC. Autopsy of the sinonasal tissue revealed a reduction in the number of tumor cells. There was a marked reduction in the number of tumor cells in the sinonasal tissue compared to that in the invaded brain tissue. The effectiveness of radiotherapy could depend on the histopathological components and location of the lesion, even in the same patient.

Semaphorin signaling via MICAL3 induces symmetric cell division to expand breast cancer stem-like cells.

Cancer stem-like cells (CSCs) are expanded in the CSC niche by increased frequency of symmetric cell divisions at the expense of asymmetric cell divisions. The symmetric division of CSCs is important for the malignant properties of cancer; however, underlying molecular mechanisms remain largely elusive. Here, we show a cytokine, semaphorin 3 (Sema3), produced from the CSC niche, induces symmetric divisions of CSCs to expand the CSC population. Our findings indicate that stimulation with Sema3 induced sphere formation in breast cancer cells through neuropilin 1 (NP1) receptor that was specifically expressed in breast CSCs (BCSCs). Knockdown of MICAL3, a cytoplasmic Sema3 signal transducer, greatly decreased tumor sphere formation and tumor-initiating activity. Mechanistically, Sema3 induced interaction among MICAL3, collapsin response mediator protein 2 (CRMP2), and Numb. It appears that activity of MICAL3 monooxygenase (MO) stimulated by Sema3 is required for tumor sphere formation, interaction between CRMP2 and Numb, and accumulation of Numb protein. We found that knockdown of CRMP2 or Numb significantly decreased tumor sphere formation. Moreover, MICAL3 knockdown significantly decreased Sema3-induced symmetric divisions in NP1/Numb-positive BCSCs and increased asymmetric division that produces NP1/Numb negative cells without stem-like properties. In addition, breast cancer patients with NP1-positive cancer tissues show poor prognosis. Therefore, the niche factor Sema3-stimulated NP1/MICAL3/CRMP2/Numb axis appears to expand CSCs at least partly through increased frequency of MICAL3-mediated symmetric division of CSCs.

Integrated genetic and epigenetic analysis of cancer-related genes in non-ampullary duodenal adenomas and intramucosal adenocarcinomas.

The molecular and clinical characteristics of non-ampullary duodenal adenomas and intramucosal adenocarcinomas are not fully understood because they are rare. To clarify these characteristics, we performed genetic and epigenetic analysis of cancer-related genes in these lesions. One hundred and seven non-ampullary duodenal adenomas and intramucosal adenocarcinomas, including 100 small intestinal-type tumors (90 adenomas and 10 intramucosal adenocarcinomas) and 7 gastric-type tumors (2 pyloric gland adenomas and 5 intramucosal adenocarcinomas), were investigated. Using bisulfite pyrosequencing, we assessed the methylation status of CpG island methylator phenotype (CIMP) markers and MLH1. Then using next-generation sequencing, we performed targeted exome sequence analysis within 75 cancer-related genes in 102 lesions. There were significant differences in the clinicopathological and molecular variables between small intestinal- and gastric-type tumors, which suggests the presence of at least two separate carcinogenic pathways in non-ampullary duodenal adenocarcinomas. The prevalence of CIMP-positive lesions was higher in intramucosal adenocarcinomas than in adenomas. Thus, concurrent hypermethylation of multiple CpG islands is likely associated with development of non-ampullary duodenal intramucosal adenocarcinomas. Mutation analysis showed that APC was the most frequently mutated gene in these lesions (56/102; 55%), followed by KRAS (13/102; 13%), LRP1B (10/102; 10%), GNAS (8/102; 8%), ERBB3 (7/102; 7%), and RNF43 (6/102; 6%). Additionally, the high prevalence of diffuse or focal nuclear ß-catenin accumulation (87/102; 85%) as well as mutations of WNT pathway components (60/102; 59%) indicates the importance of WNT signaling to the initiation of duodenal adenomas. The higher than previously reported frequency of APC gene mutations in small bowel adenocarcinomas as well as the difference in the APC mutation distributions between small intestinal-type adenomas and intramucosal adenocarcinomas may indicate that the adenoma-carcinoma sequence has only limited involvement in duodenal carcinogenesis. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Clinicopathological significance of heterogeneic ezrin expression in poorly differentiated clusters of colorectal cancers.

Multicellular structures, such as tumor buddings and poorly differentiated clusters (PDC), exist at the invasive front of colorectal cancers (CRC). Although it has been reported that CRC with PDC showed frequent lymph node metastases with a worse prognosis, the molecular markers of PDC that are responsible for prognosis have not been identified. We here noticed for the first time that Ezrin, a regulator of the actin cytoskeleton, is expressed in the corner cells of PDC. We then aimed to verify whether heterogeneous Ezrin expression in PDC predicts the prognosis of CRC patients. We immunohistochemically analyzed Ezrin expression in PDC of 184 patients with completely resected stages I-III CRC. We established the Ezrin corner score (ECS), which quantifies the tendency of Ezrin-positive cells to accumulate at the corners of PDC. On the basis of ECS values, 2 indices, the mean ECS and the number of PDC with high ECS, were obtained. Both indices were significantly higher in CRC with lymphatic invasion, higher PDC grade, and presence of micropapillary (MP) PDC. The mean ECS-high group showed shorter recurrence-free survival than the mean ECS-low group but without significance. The other index, the number of ECS-high PDC, was significantly associated with recurrence-free survival. These results suggest that Ezrin is involved in PDC progression and lymphatic invasion, and that ECS may be a marker for aggressive PDC.

Upregulation of multiple signaling pathways by Dock5 deletion in epithelial cells.

Purpose: Rupture of lens cataract (RLC) is a hereditary mouse model that shows spontaneous rupture of the lens at the posterior pole at 45-100 days of age. The responsible gene for this phenotype was identified as Dock5, a guanine nucleotide exchange factor for small GTPase Rac1. This study was performed to elucidate the pathway initiating this phenotype. Methods: We examined the RNA expression by microarray in lens epithelial cells (LECs) from wild-type and RLC mice at the pre-rupture age of 21 days. We applied the list of altered genes to an Ingenuity Pathway Analysis (IPA) to predict the pathways that are altered upon dedicator of cytokinesis-5 (Dock5) protein loss. The activation status of the predicted pathways was examined by western blotting in the cultured epithelial cells treated with a Dock5 inhibitor. Results: The highest-scored network was "Antimicrobial Response, Inflammatory Response, Dermatological Diseases and Conditions." In that network, it is predicted that extracellular signal-regulated kinase (Erk) is activated in LECs from RLC mice. Our test confirmed that Erk was more phosphorylated in the LECs at the equator in both Dock5-knockout mice and RLC mice. In an in vitro experiment of the cultured epithelial cells, the inhibition of Dock5 activity significantly induced Erk activation. It was also confirmed that Akt (cellular homolog of murine thymoma virus akt8 oncogene, also called protein kinase B) and nuclear factor-kappa B (NFκB), predicted to be the key molecules in two other high-scoring networks by IPA, were activated upon Dock5 inhibition in the cultured epithelial cells. Conclusions: Dock5 participates in epithelial cell maintenance by regulating gene expression.

A diagnostic marker for superficial urothelial bladder carcinoma: lack of nuclear ATBF1 (ZFHX3) by immunohistochemistry suggests malignant progression.

BACKGROUND: Pathological stage and grade have limited ability to predict the outcomes of superficial urothelial bladder carcinoma at initial transurethral resection (TUR). AT-motif binding factor 1 (ATBF1) is a tumor suppressive transcription factor that is normally localized to the nucleus but has been detected in the cytoplasm in several cancers. Here, we examined the diagnostic value of the intracellular localization of ATBF1 as a marker for the identification of high risk urothelial bladder carcinoma. METHODS: Seven anti-ATBF1 antibodies were generated to cover the entire ATBF1 sequence. Four human influenza hemagglutinin-derived amino acid sequence-tagged expression vectors with truncated ATBF1 cDNA were constructed to map the functional domains of nuclear localization signals (NLSs) with the consensus sequence KR[X10-12]K. A total of 117 samples from initial TUR of human bladder carcinomas were analyzed. None of the patients had received chemotherapy or radiotherapy before pathological evaluation. RESULTS: ATBF1 nuclear localization was regulated synergistically by three NLSs on ATBF1. The cytoplasmic fragments of ATBF1 lacked NLSs. Patients were divided into two groups according to positive nuclear staining of ATBF1, and significant differences in overall survival (P = 0.021) and intravesical recurrence-free survival (P = 0.013) were detected between ATBF1+ (n = 110) and ATBF1- (n = 7) cases. Multivariate analysis revealed that ATBF1 staining was an independent prognostic factor for intravesical recurrence-free survival after adjusting for cellular grading and pathological staging (P = 0.008). CONCLUSIONS: Cleavage of ATBF1 leads to the cytoplasmic localization of ATBF1 fragments and downregulates nuclear ATBF1. Alterations in the subcellular localization of ATBF1 due to fragmentation of the protein are related to the malignant character of urothelial carcinoma. Pathological evaluation using anti-ATBF1 antibodies enabled the identification of highly malignant cases that had been overlooked at initial TUR. Nuclear localization of ATBF1 indicates better prognosis of urothelial carcinoma.

Regulation of Ripply1 expression in MDCK organoids.

Epithelial organs are made of a well-polarized monolayer of epithelial cells, and their morphology must be maintained for their proper function. To examine the genes that are specifically expressed in the late stages of cystogenesis and are involved in maintaining the morphology of the mature cysts, we performed a microarray analysis comparing the mRNA expression between the early and late stages of Madin-Darby Canine Kidney (MDCK) cystogenesis. We found that one of the gene candidates, Ripply1, was expressed higher in the late stages, and its expression was also transiently much higher in the early stages. Although the protein expression showed similar kinetics, depletion of Ripply1 had only a slight effect on organoid growth. Unexpectedly, we found that the Ripply1 protein is degraded by the proteasome system. Mutant analysis suggests that Ripply1 is not ubiquitinated directly, but rather is degraded only after binding to Transducin-like Enhancer of Split (TLE)1, a transcriptional repressor. Ripply1 is degraded in the nucleus, and this degradation is inhibited during the mitosis. These data indicate for the first time that Ripply1 expression is regulated at the protein level.

Rheumatoid nodule in the lower lip of a patient with rheumatoid arthritis: a novel case report and review of literature.

PURPOSE: Rheumatoid nodules are a well-characterized common extra-articular manifestation of rheumatoid arthritis. However, the occurrence of a rheumatoid nodule in the oral mucosa is extremely rare. PATIENTS AND METHODS: We present the case of a rheumatoid nodule in the lower lip, which rarely presents with variations in the clinical manifestation, that occurred in a 48-year-old female patient with rheumatoid arthritis. The nodule was totally excised under the clinical diagnosis of either a fibroma or salivary gland lesion. RESULTS: On histopathologic examination, within the deep mucosa, a necrobiotic nodule surrounded by elongated histiocytic cells with a focal palisaded arrangement. The lesion was diagnosed postoperatively as a rheumatoid nodule from the histopathologic and clinical findings. CONCLUSIONS: Few studies have been performed of oral rheumatoid lesions; however, a review of the published data showed that this is the first case of a rheumatoid nodule in the lower lip of a patient with rheumatoid arthritis.

Narrow band imaging-guided endoscopic biopsy for intraventricular and paraventricular brain tumors: clinical experience with 14 cases.

BACKGROUND: Narrow-band imaging (NBI) has been confirmed as a useful endoscopic technique to distinguish neoplasm from normal tissue, on the basis of the enhanced neovascularity of tumor tissue. NBI-guided tissue biopsy for laryngopharyngeal and digestive lesions is a novel methodology, but the feasibility for central nervous system tumors remains unclear. The aim of our study was to evaluate the feasibility of NBI-guided biopsy for intraventricular and paraventricular tumor. METHODS: Fourteen patients with intraventricular or paraventricular tumors underwent neuroendoscopic biopsy using a videoscope with NBI. Ventricular walls and tumors were observed using conventional imaging, followed by NBI. Colors of ventricle walls and tumors visualized using NBI were compared to those visualized under conventional imaging. Extracted specimens were stained using CD31 antibody and numbers of microvessels in each specimen were counted for analyzing vascular density. RESULTS: Normal ventricle walls were a similar color under conventional imaging and NBI. Tumor surfaces appeared to be cyan in color under NBI. Vessels on the tumor were more clearly visualized with NBI than with conventional imaging. NBI was able to identify tumor surfaces that were not perceptible on conventional imaging. All specimens in the lesion surfaces from cyan-colored areas under NBI contained tumor cells. Specimens extracted from regions that appeared cyan in color under NBI (51.0 vessels/mm(2)) had significantly greater vascular density than regions that appeared a normal color (17.4 vessels/mm(2); p = 0.039). CONCLUSION: NBI-guided biopsy of intraventricular and paraventricular tumors is feasible for visualizing tumor surface-enhancing neovascularities. NBI would contribute to accurate histological diagnosis while minimizing injury to surrounding structures.

Fatal arrythmia in a young man after COVID-19 vaccination: An autopsy report.

RATIONALE: The benefits of COVID-19 mRNA vaccination are claimed to be substantial; however, vaccination-related myocarditis and pericarditis have also been observed globally, particularly among young men. In most cases, the symptoms are mild and resolve on their own; however, fatal cases have rarely been described. PATIENT CONCERNS: A healthy 40-year-old Japanese man suddenly experienced tachycardia and lost consciousness 2 days after vaccination. Continued resuscitation recovered the spontaneous heartbeat; however, the patient did not regain consciousness and died 9 days later. Electrocardiography after resuscitation showed marked ST-segment depression and incomplete right bundle branch block. Influenza antigen and polymerase chain reaction tests for SARS-CoV-2 were negative. DIAGNOSES: Fatal arrhythmia after a second COVID-19 mRNA vaccination. INTERVENTIONS: We performed an autopsy and studied the material morphologically and immunohistochemically. OUTCOMES: At autopsy, several small inflammatory foci with cardiomyocytic necrosis were scattered in the right and left ventricles, with a propensity for the right side. Some inflammatory foci were located near the atrioventricular nodes and His bundles. The infiltrating cells predominantly consisted of CD68-positive histiocytes, with a small number of CD8-positive and CD4-positive T cells. In this case, myocarditis was focal and mild, as is mostly observed following COVID-19 mRNA vaccination. However, the inflammatory foci were close to the conduction system and were considered the cause of fatal arrhythmia. LESSONS: Although the benefits of COVID-19 vaccination appear to outweigh the side effects, it should be noted that fatal arrhythmias may rarely occur, and caution should be taken if individuals, particularly young men, complain of any symptoms after vaccination.

[Specimen misidentification in pathology laboratory: trends and measures].

Specimen misidentification in pathology laboratories may have serious consequences. Reports on the frequency of errors in pathology laboratories in Japan are rare. We reviewed near-miss and incident reports over 7 years in our laboratory, extracted those associated with misidentification, analyzed annual changes in numbers and content, and discussed the problems faced and measures taken to prevent misidentification. Of 113,447 pathological cases, 88 (0.078%) reports were associated with misidentification. Of these 88 misidentification cases, 19% occurred before and during accessioning, 16% during dissecting and sectioning, 30% during embedding, 13% during tissue cutting and slide mounting, 19% during slide submitting, and 3% during diagnosis. Two cases (2.3%) of misidentification were detected after diagnosis; however, misidentification did not appear to cause adverse effects in any patient. The frequency of events is similar to that reported in the literature; specimen misidentification was noted in 0.1-0.2% of cases in a modern pathology laboratory. Two-thirds of misidentification events occurred associated with gross specimens, similar to findings in other studies. With the introduction of new technologies that minimize the possibility of human errors (e.g., barcode reading, digital imaging of every specimen, and installation of a glass slide printer), education on medical safety, and the use of multiple safety nets (e.g., diagnosis cancelling and slide checking), errors have decreased, but have not been eliminated completely. Recording errors and reporting them to the hospital and social community, and maintaining a sustainable quality improvement system is very important to reduce errors in pathology.

[Surgical resection of multiple liver metastases of rectal neuroendocrine tumors].

We report a case of surgically resected multiple liver metastases of rectal neuroendocrine tumors (NET), which could not be controlled by medical treatment. A 66-year-old man was diagnosed as having multiple liver metastases of rectal NET 5 years after the initial diagnosis. Although we performed 5 rounds of transcatheter arterial infusion (TAI) and administered 4 cycles of 5-fluorouracil, Leucovorin, and oxaliplatin( mFOLFOX6), the metastasis gradually spread. The patient was admitted to our hospital to undergo hepatectomy. Extended right hepatectomy and partial resection of the lateral segment were performed. The pathological diagnosis was metastasis of rectal NET and it was classified as grade 2 NET according to the 2010 World Health Organization (WHO) classification. The patient received intramuscular injections of sustained-release octreotide( 30 mg every 4 weeks) after surgery. One year and 2 months after surgery, he shows no signs of recurrence.

Ureteral Metastasis of Colonic Adenocarcinoma with Enteroblastic Differentiation: A Rare Case to be Distinguished from Clear Cell Adenocarcinoma of the Urinary Tract.

Adenocarcinomas with enteroblastic differentiation are rare clear cell tumors that are positive for enteroblastic markers. Enteroblastic differentiation is particularly uncommon in colorectal adenocarcinomas. Herein, we report a case of clear cell adenocarcinoma with enteroblastic differentiation in the sigmoid colon of a 38-year-old Japanese woman that metastasized to the lower left ureter. After neoadjuvant chemotherapy, the patient underwent low anterior resection. The tumor consisted of tubular, cribriform, and focal micropapillary proliferation of clear cells immunopositive for spalt-like transcription factor 4 (SALL4), glypican 3, and alpha-fetoprotein. Six months after the colonic resection, a tumor was found in the left lower ureter, which was resected. The ureteral tumor revealed clear cell adenocarcinoma, which was identical to the colonic tumor proliferating in the ureteral mucosa. Metastatic ureteral tumors are rare. We performed a literature search and found only 50 reported cases of ureteral metastases from colorectal cancer. Of these, only 10 metastatic tumors were identified in the ureteral mucosa. No case of ureteral metastasis of clear cell colorectal adenocarcinoma or colorectal adenocarcinoma with enteroblastic differentiation has been reported. Hence, it can be challenging to distinguish them from clear cell adenocarcinoma of the urinary tract and/or clear cell urothelial carcinoma. This paper discussed the differential diagnosis of these tumors and reviewed the clinicopathological features of colorectal carcinomas metastasizing to the ureter.