Comprehensive genetic features of gastric mixed adenoneuroendocrine carcinomas and pure neuroendocrine carcinomas.

We aimed to determine the pathogenesis of gastric mixed adenoneuroendocrine carcinoma (MANEC) and pure neuroendocrine carcinoma (NEC), which is largely unknown. Targeted DNA sequencing was performed on 34 tumor samples from 21 patients - 13 adenocarcinoma (ADC)/NEC components from MANECs and eight pure NECs - and 21 matched non-neoplastic gastric tissues. Mutational profiles of MANECs/NECs were compared with those of other tumors using public databases. The majority (64.1%; 59/92) of mutations in MANEC were shared by both ADC and NEC components. TP53 was the most commonly mutated gene in MANEC (69.2%, 9/13) and pure NEC (87.5%, 8/9). All TP53 mutations in MANEC were pathogenic mutations and were shared by both ADC and NEC components. A subset of TP53WT MANECs had a microsatellite-unstable phenotype or amplifications in various oncogenes including ERBB2 and NMYC, and the only TP53WT pure NEC harbored MYC amplification. Compared to NEC in other organs, NECs arising from the stomach had unique features including less frequent RB1 mutations. Differentially altered genes of MANEC ADC components were significantly associated with receptor tyrosine kinase signaling pathways, while differentially altered genes of MANEC NEC components were significantly associated with the NOTCH signaling pathway. Our data provide evidence suggesting a possible clonal origin of ADC and NEC components of MANEC, and we found that gastric MANECs and pure NECs are distinct entities with unique mutational profiles and underlying protein networks. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Association of Plasma Marker of Oxidized Lipid with Histologic Plaque Instability in Patients with Peripheral Artery Disease.

BACKGROUND: The association between oxidized low-density lipoprotein (OxLDL) and plaque instability in coronary and carotid artery disease is well established. However, the association between OxLDL and the histologic changes of plaque in peripheral artery disease has not been clearly elucidated. This study aims to investigate the association between plasma OxLDL and histologic plaque instability in patients with peripheral artery disease. METHODS: Prospectively obtained plaques from 48 patients who underwent endovascular atherectomy (n = 20), surgical endarterectomy (n = 9), or bypass surgery (n = 19) for treatment of atherosclerotic femoropopliteal artery disease were evaluated for histologic fibrosis, sclerosis, calcification, necrosis, cholesterol cleft, and foamy macrophages using hematoxylin and eosin, oil red O, and immunohistochemical staining. Unstable plaques were defined as plaques that were positive for foamy macrophages and with lipid content of more than 10% of the total plaque area. Plasma OxLDL levels were measured using an enzyme-linked immunosorbent assay (Mercodia AB, Uppsala, Sweden). RESULTS: Of the 48 patients, 26 (54%) had unstable plaques. The unstable plaque group was younger, had fewer angiographic total occlusions, less calcification, and more CD68-positive and LOX-1-positive cells than the stable plaque group. Plasma OxLDL levels were significantly higher in the unstable plaque group than in the stable plaque group (57.4 ± 13.9 vs. 47.2 ± 13.6 U/L, P = 0.014). Multivariate analysis revealed that plasma OxLDL level, smoking, angiographic nontotal occlusion, and statin nonuse were independent predictors of unstable plaque. CONCLUSIONS: Among patients with peripheral artery disease, the histologic instability of femoropopliteal plaque was independently associated with high plasma OxLDL, smoking, nontotal occlusion, and statin nonuse. Further large-scale studies are necessary to evaluate the role of noninvasive OxLDL measurement for predicting plaque instability and future adverse vascular event.

Renal epithelioid angiomyolipoma: Histopathologic review, immunohistochemical evaluation and prognostic significance.

Epithelioid angiomyolipoma (EAML) is considered to be a potentially malignant tumor and requires a differential diagnosis from renal cell carcinoma. In this study, we assessed the clinicopathologic features of renal EAML and evaluated the prognostic significance. Among 78 angiomyolipoma (AML) patients, a total of 5 EAMLs were identified, accounting for 6.4% of the total AML cases. The mean age was 41.4 years, and the average tumor size was 12.7 cm in diameter. Association of tuberous sclerosis complex was identified in two cases. One EAML case showed malignant behavior with local recurrence and distant metastasis. The malignant EAML had a larger tumor size, a higher percentage of epithelioid component and atypical epithelioid cells, ≥2 mitoses per 10 high power fields with atypical mitosis, necrosis, extrarenal extension, and carcinoma-like growth pattern. Furthermore, the malignant case revealed p53 immunoreactivity and decreased membranous E-cadherin expression. Pathologic evaluation of adverse prognostic factors will be helpful for risk stratification and prognosis estimation of EAML patients.

Application of Small Cell Lung Cancer Molecular Subtyping Markers to Small Cell Neuroendocrine Carcinoma of the Cervix: NEUROD1 as a Poor Prognostic Factor.

Cervical small cell neuroendocrine carcinoma (CSCNEC) is a rare, aggressive type of cervical cancer. The treatment for CSCNEC follows the chemotherapeutic regimens used for small cell lung cancer (SCLC), with which it shares similar clinical and histologic features. For the first time, we applied neuroendocrine (NE) and SCLC molecular subtyping immunohistochemical markers [achaete-scute homolog 1 (ASCL1), neurogenic differentiation factor 1 (NEUROD1), POU class 2 homeobox 3 (POU2F3), and yes-associated protein 1] in 45 patients with CSCNEC. For the combined NE score, 51.1% of NE-high and 48.9% of NE-low subtypes were identified. The NE-high subtype tended to show worse progression-free survival and overall survival (OS) than the NE-low subtype ( P =0.059 and P =0.07, respectively). Applying the SCLC molecular subtyping, 53.3% of cases were identified as NEUROD1-dominant, 17.8% as ASCL1-dominant, 13.3% as YAP-dominant, and 4.4% as POU2F3-dominant, while 11.1% of cases showed negative expression for all markers; the distribution was different from that of SCLC. The NEUROD1-dominant subtype exhibited the worst OS, while the POU2F3 subtype exhibited the best OS ( P =0.003), similar to SCLC. In addition, the ASCL1-dominant and NEUROD1-dominant subtypes showed high NE scores, while yes-associated protein 1-dominant and POU2F3-dominant subtypes showed low NE scores ( P =0.008). In multivariate analysis, the NEUROD1 expression was further identified as the independent prognostic factor for worse OS, together with the high FIGO stage. CSCNEC was revealed to be a heterogeneous disease with different biological phenotypes and to share some similarities and differences with SCLC. Regarding the ongoing development of tailored treatments based on biomarkers in SCLC, the application of biomarker-driven individualized therapy would improve clinical outcomes in patients with CSCNEC.

Comparison of four histological scoring systems for autoimmune hepatitis to improve diagnostic sensitivity.

BACKGROUND/AIMS: The histological criteria in the 1999 and 2008 scoring systems proposed by the International Autoimmune Hepatitis Group (IAIHG) have their inherent limitations in diagnosing autoimmune hepatitis (AIH). In this study, we evaluated the histology components of four scoring systems (1. revised original scoring system ["1999 IAIHG"], 2. simplified scoring system ["2008 IAIHG"], 3. modified histologic criteria ["2017 UCSF"], and 4. a new histologic criteria proposed by the International AIH Pathology Group ["2022 IAHPG"]) in AIH patients. METHODS: Medical records and liver biopsies were retrospectively reviewed for 68 patients from two independent medical institutions, diagnosed with AIH based on the 1999 IAIHG system between 2006 and 2016. The histological features were reviewed in detail, and the four histological scoring systems were compared. RESULTS: Out of the 68 patients, 56 (82.4%) patients met the "probable" or "definite" AIH criteria of the 2008 IAIHG system, and the proportion of histologic score 2 (maximum) was 40/68 (58.8%). By applying the 2017 UCSF criteria, the number of histology score 2 increased to 60/68 (88.2%), and "probable" or "definite" AIH cases increased to 61/68 (89.7%). Finally, applying the 2022 IAHPG histology score resulted in the highest number of cases with histologic score 2 (64/68; 94.1%) and with a diagnosis of "probable" or "definite" AIH (62/68; 91.2%). CONCLUSION: The recently proposed UCSF/IAHPG histological criteria increased the histology score of AIH. Substituting the histology component of the 2008 IAIHG system with the 2022 IAHPG criteria increased the sensitivity for diagnosing AIH (≥"Probable AIH") from 82.4% to 91.2%.

Low HES-1 and positive DLL4 expression predicts poor prognosis of colorectal cancers.

Hairy and enhancer of split-1 (HES-1) is a downstream transcription factor and delta-like 4 (DLL4) is a ligand of the Notch signalling pathway. HES-1 and DLL4 expression are known to have an association with the progression and metastasis of cancers. We evaluated HES-1 and DLL4 expression and assessed their correlation with biological behaviour and prognostic significance of 327 colorectal cancers. Low HES-1 expression was identified in 210 (64.2%) cases and was significantly correlated with large tumour size, lymphovascular invasion, and distant metastasis. DLL4 was positive in 132 (40.4%) cases and significantly correlated with perineural invasion, distant metastasis, and involved resection margin. Patients with low HES-1 expression showed significantly worse overall survival than patients with high HES-1 expression [hazard ratio (HR)=3.017; 95% confidence interval (CI) 1.880-4.841; p<0.001]. The overall survival of patients with positive DLL4 expression was significantly worse than that of patients with negative DLL4 expression (HR=2.922; 95% CI 1.976-4.322; p<0.001). Furthermore, the combined HES-1lowDLL4positive expression group showed the worst overall survival compared to other groups (p<0.001) and was an independent poor prognostic factor of colorectal cancer patients. Thus, low HES-1 and positive DLL4 expression are associated with aggressive biological behaviour and can be used as prognostic factors in colorectal cancer patients.

Low MST1/2 and negative LATS1/2 expressions are associated with poor prognosis of colorectal cancers.

Mammalian STe20-like protein kinase 1/2 (MST1/2) and large tumor suppressor homolog 1/2 (LATS1/2) are the core components of the tumor-suppressive Hippo pathway. Dysregulation of this pathway is associated with the progression and metastasis of various cancers. However, MST1/2 and LATS1/2 expressions have not been systematically evaluated in colorectal cancers. We evaluated the clinicopathologic correlation and prognostic significance of MST1/2 and LATS1/2 immunohistochemical expressions in 327 colorectal cancer patients. Low MST1/2 expression, identified in 235 (71.9 %) cases, was significantly associated with poor differentiation (P = 0.018) and large size (P < 0.001) of the tumor. Negative LATS1/2 expression, identified in 226 (69.1 %) cases, was significantly correlated with low MST1/2 expression (P = 0.044). Low MST1/2 and negative LATS1/2 expressions were significantly associated with poor overall survivals (P = 0.015 and P = 0.038, respectively). Furthermore, the combined MST1/2lowLATS1/2negative expression group showed significantly worse overall survival than other groups (P = 0.003), and considered as an independent poor prognostic factor for colorectal cancer patients (hazard ratio = 1.720; 95 % confidence interval, 1.143-2.588; P = 0.009). Low MST1/2 and negative LATS1/2 expressions may serve as prognostic indicators in patients with colorectal cancer.

Multiple Eruptive Epithelioid Hemangiomas on the Right Upper Extremity in an Asian Man.

Epithelioid hemangioma is a rare benign vascular neoplasm. Recently, the term "multiple eruptive epithelioid hemangioma" has been proposed for epithelioid hemangioma with distinct features. It is different from usual epithelioid hemangioma because of the multifocal distributions in various body regions with an eruptive onset. In addition, the histopathology of multiple eruptive epithelioid hemangioma shows increased cellular proliferation, mitosis, and nuclear pleomorphism and positive findings for FOS-B compared to classic epithelioid hemangioma. Herein, we report the case of a 59-year-old man with unusual manifestations suitable for multiple eruptive epithelioid hemangioma. He had multiple erythematous to purple-red dome-shaped nodules on the right hand, arm, and shoulder. The initial lesion was a solitary erythematous nodule on the right hand that abruptly extended to the right arm and shoulder. Microscopically, the tumor was a well-demarcated dermal nodule and showed capillary sized vascular structures. Vascular structures had epithelioid endothelial cells with abundant eosinophilic cytoplasm and vesicular nuclei. The tumor cells showed mild nuclear pleomorphism and a few mitosis and feature of resembling cobble stone was observed. In immunohistochemistry, CD31 and CD34 were positive in the endothelial cells. The endothelial cells showed nuclear positivity in FOS-B. Based on the clinical and histopathological findings, the final diagnosis was multiple eruptive epithelioid hemangiomas. This is the first report of multiple eruptive epithelioid hemangiomas in an Asian man after the term had been introduced.

Automated Diagnosis of Cervical Intraepithelial Neoplasia in Histology Images via Deep Learning.

Artificial intelligence has enabled the automated diagnosis of several cancer types. We aimed to develop and validate deep learning models that automatically classify cervical intraepithelial neoplasia (CIN) based on histological images. Microscopic images of CIN3, CIN2, CIN1, and non-neoplasm were obtained. The performances of two pre-trained convolutional neural network (CNN) models adopting DenseNet-161 and EfficientNet-B7 architectures were evaluated and compared with those of pathologists. The dataset comprised 1106 images from 588 patients; images of 10% of patients were included in the test dataset. The mean accuracies for the four-class classification were 88.5% (95% confidence interval [CI], 86.3-90.6%) by DenseNet-161 and 89.5% (95% CI, 83.3-95.7%) by EfficientNet-B7, which were similar to human performance (93.2% and 89.7%). The mean per-class area under the receiver operating characteristic curve values by EfficientNet-B7 were 0.996, 0.990, 0.971, and 0.956 in the non-neoplasm, CIN3, CIN1, and CIN2 groups, respectively. The class activation map detected the diagnostic area for CIN lesions. In the three-class classification of CIN2 and CIN3 as one group, the mean accuracies of DenseNet-161 and EfficientNet-B7 increased to 91.4% (95% CI, 88.8-94.0%), and 92.6% (95% CI, 90.4-94.9%), respectively. CNN-based deep learning is a promising tool for diagnosing CIN lesions on digital histological images.

Clinical evaluation of a droplet digital PCR assay for detecting POLE mutations and molecular classification of endometrial cancer.

OBJECTIVE: We evaluated droplet digital polymerase chain reaction (ddPCR) method for detecting POLE mutations in endometrial cancer (EC) and guiding its molecular classification. METHODS: We reviewed 240 EC specimens from our hospital database. A ddPCR assay was used to identify POLE mutations at 5 known hotspots (P286R, S297F, V411L, A456P, and S459F). Expressions of p53 and mismatch repair proteins were identified using immunohistochemistry. RESULTS: The ddPCR assay identified POLE mutations in 10.8% of patients. The most common mutation was V411L (61.54%), followed by P286R (23.07%), S459F (7.69%), S297F (3.85%), and A456P (3.85%). Eight/one cases had positive ddPCR but negative Sanger sequencing/next-generation sequencing, respectively. Molecular classification revealed p53-mutated subtype as significantly more common for tumors with a high International Federation of Gynecology and Obstetrics (FIGO) grade, deep myometrial invasion, lymphovascular space invasion, advanced stage, and high/advanced risk groups; the POLE mutated group was more frequent in the low stage and low/intermediate risk group. Survival analyses revealed the poorest outcomes for p53-mutated EC, while mismatch repair-deficient and no specific molecular profile ECs had similar progression-free survival (PFS) outcomes, and POLE-mutated ECs had the best PFS outcome (p<0.001). When only intermediate, high-intermediate, and high-risk groups were analyzed for subgroups, molecular classification still showed differences both in PFS (p=0.003) and overall survival (p=0.017). CONCLUSION: Hotspot POLE mutations can be detected using the ddPCR assay. We suggest simultaneously evaluating POLE mutation status using ddPCR and p53/mismatch repair protein expressions using immunohistochemistry, which can rapidly and accurately determine the molecular subtype of EC.

Mucinous Cystadenoma of the Testis: A Case Report with Immunohistochemical Findings.

Mucinous cystadenoma of the testis is a very rare tumor. Herein, we report a case of mucinous cystadenoma arising in the testis of a 61-year-old man, along with a literature review. Computed tomography showed a 2.5-cm-sized poorly enhancing cystic mass. Grossly, the tumor was a unilocular cystic mass filled with mucinous material and confined to the testicular parenchyma. Histologically, the cyst had a fibrotic wall lined by mucinous columnar epithelium without atypia. Immunohistochemical staining was positive for cytokeratin 20 and CDX2, as well as focally positive for cytokeratin 7. The pathologic diagnosis was mucinous cystadenoma.

Comparison of the FDA and ASCO/CAP Criteria for HER2 Immunohistochemistry in Upper Urinary Tract Urothelial Carcinoma.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) is one of the known oncogenes in urothelial carcinoma. However, the association between HER2 and the prognosis of upper urinary tract urothelial carcinoma (UUTUC) has not yet been fully clarified. The aim of this study was to evaluate HER2 expression using the United States Food and Drug Administration (FDA) criteria and American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) criteria and compare their prognostic significance in UUTUC. METHODS: HER2 expression was evaluated in 144 cases of UUTUC by immunohistochemistry (IHC) using tissue microarrays. We separately analyzed HER2 expression using the FDA and ASCO/CAP criteria. The IHC results were categorized into low (0, 1+) and high (2+, 3+) groups. RESULTS: Using the FDA criteria, 94 cases were negative, 38 cases were 1+, nine cases were 2+, and three cases were 3+. Using the ASCO/CAP criteria, 94 cases were negative, 34 cases were 1+, 13 cases were 2+, and three cases were 3+. Four cases showing 2+ according to the ASCO/CAP criteria were reclassified as 1+ by the FDA criteria. High HER2 expression by both the FDA criteria and ASCO/CAP criteria was significantly associated with International Society of Urological Pathology high grade (p = .001 and p < .001). The high HER2 expression group classified with the FDA criteria showed significantly shorter cancer-specific survival (p = .004), but the HER2 high and low expression groups classified with the ASCO/CAP criteria did not show significant differences (p = .161) in cancer-specific survival. CONCLUSIONS: HER2 high expression groups were significantly associated with shorter cancer-specific survival, and our study revealed that the FDA criteria are more suitable for determining HER2 expression in UUTUC.

HER2 Protein Overexpression and Gene Amplification in Plasmacytoid Urothelial Carcinoma of the Urinary Bladder.

AIM: HER2 overexpression has been reported in a minority of urothelial carcinomas, but little is known about HER2 protein expression and gene alterations in plasmacytoid urothelial carcinoma, a rare and aggressive variant. The aim of this study was to clarify the HER2 status in plasmacytoid urothelial carcinomas. METHODS: Six cases of plasmacytoid urothelial carcinoma were included, in which we evaluated HER2 protein expression by immunohistochemistry (IHC) and HER2 gene amplification by fluorescence in situ hybridization (FISH). RESULTS: The patients' ages ranged from 57 to 83 years (mean age, 71 years). Five patients were male and one was female. The ratio of the plasmacytoid component ranged from 30% to 100% (mean, 77%). HER2 expression score was 3+ in 4 cases, 2+ in one case, and negative in one case. HER2 gene amplification was positive in 3 cases, of which 2 cases showed a 3+ HER2 IHC score but one case was negative for HER2 IHC. Another 2 cases showed equivocal HER2 FISH results, and one remaining case was negative for HER2 FISH. CONCLUSION: Our observation that plasmacytoid urothelial carcinomas frequently demonstrated HER2 protein overexpression provides supporting evidence that HER2 may be a potential therapeutic target for plasmacytoid urothelial carcinoma.

Frequent aerogenous spread with decreased E-cadherin expression of ROS1-rearranged lung cancer predicts poor disease-free survival.

OBJECTIVES: ROS1 rearrangement has been found in a subset of lung cancer and ROS1-rearranged tumors are sensitive to ALK kinase inhibitors. This study sought to evaluate the clinicopathological implications and histomorphological characteristics of ROS1-rearranged tumors, especially micropapillary and aerogenous spread growth and to investigate the usefulness of ROS1 immunohistochemistry as a diagnostic test for ROS1 rearrangement. MATERIALS AND METHODS: ROS1 rearrangement characterizations by fluorescence in situ hybridization and ROS1 protein and E-cadherin expression by immunohistochemistry were performed using 754 non-small cell lung cancer surgical specimens. RESULTS: ROS1 rearrangement was identified in 10 samples. Histologically, all 10 ROS1-rearranged tumors harbored an adenocarcinoma component. Significantly, we noted a high association between ROS1 rearrangement with a micropapillary component (p<0.001), aerogenous spread (p=0.002), and E-cadherin loss (p=0.049). Survival analysis showed that ROS1 rearrangement was significantly associated with a higher risk of tumor recurrence (p=0.024). The best criterion to detect ROS1-rearrangement by immunohistochemistry was an H-score of ≥100, with a sensitivity and specificity of 90% and 93.5%, respectively. CONCLUSIONS: ROS1-rearranged adenocarcinoma exhibited distinct morphological and clinicopathological features. Decreased membranous E-cadherin expression and aerogenous spread may be associated with worse disease-free survival. ROS1 immunohistochemistry correlated well with ROS1 gene rearrangement.