Artificial intelligence-based real-time histopathology of gastric cancer using confocal laser endomicroscopy.

There has been a persistent demand for an innovative modality in real-time histologic imaging, distinct from the conventional frozen section technique. We developed an artificial intelligence-driven real-time evaluation model for gastric cancer tissue using confocal laser endomicroscopic system. The remarkable performance of the model suggests its potential utilization as a standalone modality for instantaneous histologic assessment and as a complementary tool for pathologists' interpretation.

Real-time Histological Evaluation of Gastric Cancer Tissue by Using a Confocal Laser Endomicroscopic System.

BACKGROUND/AIM: The need for instant histological evaluation of fresh tissue, especially in cancer treatment, remains paramount. The conventional frozen section technique has inherent limitations, prompting the exploration of alternative methods. A recently developed confocal laser endomicroscopic system provides real-time imaging of the tissue without the need for glass slide preparation. Herein, we evaluated its applicability in the histologic evaluation of gastric cancer tissues. MATERIALS AND METHODS: A confocal laser endomicroscopic system (CLES) with a Lissajous pattern laser scanning, was developed. Fourteen fresh gastric cancer tissues and the same number of normal gastric tissues were obtained from advanced gastric cancer patients. Fluorescein sodium was used for staining. Five pathologists interpreted 100 endomicroscopic images and decided their histologic location and the presence of cancer. Following the review of matched hematoxylin and eosin (H&E) slides, their performance was evaluated with another 100 images. RESULTS: CLES images mirrored gastric tissue histology. Pathologists were able to detect the histologic location of the images with 65.7% accuracy and differentiate cancer tissue from normal with 74.7% accuracy. The sensitivity and specificity of cancer detection were 71.9% and 76.1%. Following the review of matched H&E images, the accuracy of identifying the histologic location was increased to 92.8% (p<0.0001), and that of detecting cancer tissue was also increased to 90.9% (p<0.001). The sensitivity and specificity of cancer detection were enhanced to 89.1% and 93.2% (p<0.0001). CONCLUSION: High-quality histological images were immediately acquired by the CLES. The operator training enabled the accurate detection of cancer and histologic location raising its potential applicability as a real-time tissue imaging modality.

Dedifferentiated Leiomyosarcoma of the Uterine Corpus with Heterologous Component: Clinicopathological Analysis of Five Consecutive Cases from a Single Institution and Comprehensive Literature Review.

Dedifferentiation is a very rare phenomenon in uterine leiomyosarcoma (LMS). The aim of this study was to comprehensively analyze the clinicopathological characteristics of uterine dedifferentiated LMS (DDLMS). We reviewed electronic medical records and pathology slides from five patients with uterine DDLMS and performed immunostaining. The mean age of the patients was 56 years. Two patients presented with abdominal discomfort, while in three cases the uterine tumors were detected on routine medical examination. The mean size of the tumors was 17.0 cm. Four patients underwent hysterectomy. The initial stages were distributed as IB (2/5), IIIC (2/5), and IVC (1/5). Post-operative concurrent chemoradiation therapy, radiation therapy, and chemotherapy were administered in one, one, and two patients, respectively. Despite post-operative treatment, three patients developed metastatic recurrences in the abdominal and pelvic organs. Recurrence-free survival time ranged between 4 and 30 months. Histologically, the differentiated areas demonstrated the classic morphology of malignant smooth muscle differentiation, whereas the dedifferentiated areas resembled undifferentiated pleomorphic sarcoma and were characterized by large pleomorphic tumor cells admixed with haphazardly arranged atypical cells with marked nuclear pleomorphism. All cases also exhibited heterologous components, including chondrosarcoma (CSA; 3/5) and rhabdomyosarcoma (2/5). In two cases, the heterologous components were initially detected in primary tumors. In three cases, the primary tumors did not exhibit any dedifferentiated or heterologous components. Instead, more than half of the recurrent tumors consisted of heterologous components. Three cases showed a sharp demarcation between the LMS and CSA components, while in two cases the dedifferentiated area imperceptibly merged with the differentiated component. Immunostaining revealed that the dedifferentiated components exhibited a lack of desmin immunoreactivity in three of the four examined cases. A subset of uterine LMS represents various amounts and types of dedifferentiation and heterologous components in both primary and recurrent tumors. Routine recognition of DDLMS and distinction from its mimickers are required for accurate diagnosis and further characterization of these rare tumors.

Clinicopathological and Molecular Characteristics of IDH-Wildtype Glioblastoma with FGFR3::TACC3 Fusion.

The World Health Organization Classification of Tumors of the Central Nervous System recently incorporated histological features, immunophenotypes, and molecular characteristics to improve the accuracy of glioblastoma (GBM) diagnosis. FGFR3::TACC3 (F3T3) fusion has been identified as an oncogenic driver in IDH-wildtype GBMs. Recent studies have demonstrated the potential of using FGFR inhibitors in clinical trials and TACC3-targeting agents in preclinical models for GBM treatment. However, there is limited information on the clinicopathological and genetic features of IDH-wildtype GBMs with F3T3 fusion. The aim of this study was to comprehensively investigate the clinical manifestations, histological features, and mutational profiles of F3T3-positive GBMs. Between September 2017 and February 2023, 25 consecutive cases (5.0%) of F3T3-positive GBM were extracted from 504 cases of IDH-wildtype GBM. Clinicopathological information and targeted sequencing results obtained from 25 primary and 4 recurrent F3T3-positive GBMs were evaluated and compared with those from F3T3-negative GBMs. The provisional grades determined by histology only were distributed as follows: 4 (26/29; 89.7%), 3 (2/29; 6.9%), and 2 (1/29; 3.4%). Grade 2-3 tumors were ultimately diagnosed as grade 4 GBMs based on the identification of the TERT promoter mutation and the combined gain of chromosome 7 and loss of chromosome 10 (7+/10-). F3T3-positive GBMs predominantly affected women (2.6 females per male). The mean age of patients with an F3T3-positive GBM at initial diagnosis was 62 years. F3T3-positive GBMs occurred more frequently in the cortical locations compared to F3T3-negative GBMs. Imaging studies revealed that more than one-third (12/29; 41.4%) of F3T3-positive GBMs displayed a circumscribed tumor border. Seven of the seventeen patients (41.2%) whose follow-up periods exceeded 20 months died of the disease. Histologically, F3T3-positive GBMs more frequently showed curvilinear capillary proliferation, palisading nuclei, and calcification compared to F3T3-negative GBMs. Molecularly, the most common alterations observed in F3T3-positive GBMs were TERT promoter mutations and 7+/10-, whereas amplifications of EGFR, PDGFRA, and KIT were not detected at all. Other genetic alterations included CDKN2A/B deletion, PTEN mutation, TP53 mutation, CDK4 amplification, and MDM2 amplification. Our observations suggest that F3T3-positive GBM is a distinct molecular subgroup of the IDH-wildtype GBM. Both clinicians and pathologists should consider this rare entity in the differential diagnosis of diffuse astrocytic glioma to make an accurate diagnosis and to ensure appropriate therapeutic management.

Risk Factors Affecting Clinical Outcomes of Low-risk Early-stage Human Papillomavirus-Associated Endocervical Adenocarcinoma Treated by Surgery Alone: Application of Silva Pattern.

This study aimed to report the clinical outcomes and risk factors for survival of patients with low-risk early-stage human papillomavirus-associated (HPVA) endocervical adenocarcinoma (EAC) treated with surgery alone. This retrospective study obtained the clinicopathological data of patients with early-stage HPVA EAC who underwent surgery between 2012 and 2018. The Silva pattern of invasion was determined by reviewing pathology slides. Locoregional recurrence-free survival (RFS), RFS, and overall survival were calculated, and the risk factors for survival were analyzed. One hundred seventeen patients with a median follow-up of 5.2 years (0.5-9.7 yr) were included. The most common histologic type was usual (94/117, 80.3%). The Silva pattern was A in 79 patients (67.5%), B in 30 (25.6%), and C in 8 (6.8%). The 5-year locoregional RFS, RFS, and overall survival rates were 92.4%, 87.8%, and 97.2%, respectively. The presence of intermediate-risk factors and Silva pattern C were significantly associated with worse survival. Based on these findings, patients were categorized into 2 groups: Group 1 (Silva pattern A or Silva pattern B without intermediate-risk factors) and Group 2 (Silva pattern B with intermediate-risk factors or Silva pattern C). Group 2 showed significantly worse outcomes than Group 1, including the 5-year locoregional RFS (98.6% vs 68.0%), RFS (96.4% vs 54.6%), and overall survival (100.0% vs 86.5%). In conclusion, surgery alone for early-stage HPVA EAC resulted in favorable outcomes. Consideration of the Silva pattern, in addition to well-known risk factors, could help in precise risk group stratification of low-risk, early-stage HPVA EAC.

Diagnostic utility of genetic alterations in distinguishing IDH-wildtype glioblastoma from lower-grade gliomas: Insight from next-generation sequencing analysis of 479 cases.

The accurate diagnosis and classification of gliomas are essential for appropriate treatment planning and prognosis prediction. This study aimed to investigate the molecular diagnostics of IDH-wildtype diffuse astrocytic gliomas and identify potential genetic variants that could differentiate glioblastoma (GBM) from lower-grade gliomas when DNA methylation analysis is not feasible. In total, 479 H3-and IDH-wildtype diffuse astrocytic gliomas were included in this study. All the cases were diagnosed according to the 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors. Panel sequencing data were collected, and clinicopathological information was retrieved from medical records. Genetic alterations and histological findings were analyzed to determine their diagnostic utility and prognostic implications. Out of 479 cases, 439 (91.6%) were diagnosed with GBM, including 28 cases that were molecularly diagnosed as GBM. However, 40 (8.4%) cases could not be classified according to the 2021 WHO classification and were diagnosed as lower-grade diffuse astrocytic glioma, IDH-wildtype, not elsewhere classified (LGNEC). In addition to the three genetic alterations included in the diagnostic criteria of GBM, PTEN and EGFR mutations were found to be enriched in GBM. Patients harboring mTOR pathway mutations demonstrated a more favorable prognosis and often exhibited morphology resembling subependymal giant cell astrocytoma, along with a high tumor mutational burden. Among patients with mTOR pathway mutations, those lacking molecular diagnostic features of GBM exhibited outstanding survival outcomes, even in the presence of grade 4 histology. Integration of molecular features enhanced the diagnostic accuracy of IDH-wildtype gliomas. Some molecular alterations enriched in GBM offer valuable insights for molecular diagnosis and glioma classification. Furthermore, high-grade diffuse astrocytic gliomas featuring mTOR pathway mutations in the absence of molecular diagnostic features of GBM could represent more favorable tumor types distinct from GBM.

Endocervical Adenocarcinoma Showing Microcystic, Elongated, and Fragmented (MELF) Pattern of Stromal Invasion: A Single-Institutional Analysis of 10 Cases with Comprehensive Clinicopathological Analyses and Ki-67 Immunostaining.

Microcystic, elongated, and fragmented (MELF) pattern of invasion has seldom been documented in endocervical adenocarcinoma (EAC). The aim of this study was to analyze the clinicopathological characteristics of EAC showing MELF pattern. We collected the clinicopathological information of 10 cases of EAC with the MELF pattern and conducted polymer-based immunostaining for Ki-67 (dilution 1:200, clone MIB-1) on these cases. Ki-67 expression was assessed using the average estimation within the hotspot method. All tumors were human papillomavirus-associated EAC with Silva pattern C. All except one tumor exceeded 3 cm in size. Five tumors involved the entire thickness of the cervical stroma, and four tumors extended into the parametrium. Lymphovascular space invasion was identified in six cases. Two patients developed metastatic recurrences in the para-aortic lymph nodes and lungs, respectively. The MELF area showed significantly lower Ki-67 labelling index than that of a conventional tumor area. We confirmed our previous observation that the MELF area displayed lower proliferative activity than the conventional tumor area of EAC. We also demonstrated that patients with EAC showing MELF pattern had several adverse clinicopathological characteristics reflecting aggressive behavior. On the other hand, since the frequencies of post-operative recurrence and disease-related mortality that occurred during the follow-up period were relatively low, further investigations are warranted to clarify the prognostic value of MELF pattern in EAC patients.

Endocervical Adenocarcinoma: Comprehensive Histological Review and Re-classification of 123 Consecutive Cases According to the Updated World Health Organization Classification of Female Genital Tumors.

BACKGROUND/AIM: The updated 2020 World Health Organization (WHO) classification divides endocervical adenocarcinomas (EACs) into human papillomavirus-associated (HPVA) and -independent (HPVI) tumors. The purpose of this study was to review our EAC cases and re-classify them according to the updated WHO classification. PATIENTS AND METHODS: We reviewed the hematoxylin and eosin-stained slides of 123 EACs and reclassified them according to the updated WHO classification. RESULTS: Eighty-one (65.9%) and 42 (34.1%) patients had HPVA and HPVI EACs, respectively. The usual (60/81; 74.1%) and gastric (31/42; 73.8%) types were the most common HPVA and HPVI EACs, respectively. Signet-ring cell (1/123; 0.8%), invasive stratified mucin-producing (10/123; 8.1%), clear-cell (4/123; 3.3%), mesonephric (3/123; 2.4%), and serous (1/123; 0.8%) types were uncommon. Unusual morphologies were seen, including microcystic, elongated, and fragmented patterns of stromal invasion, micropapillary growth patterns, and gastric-type adenocarcinoma in situ. CONCLUSION: We successfully reclassified all the examined cases based on morphology alone. The numbers and relative proportions of EAC histotypes were variable. We found some uncommon histotypes, as well as unusual but clinically important histological features.

Clinical outcomes and management of facial nerve in patients with parotid gland cancer and pretreatment facial weakness.

OBJECTIVES: In parotid gland cancer (PGC), it is not clear whether facial weakness always reflects tumor invasion of the facial nerve (FN) requiring nerve resection. The aims of this study were to evaluate oncological and functional outcomes in patients with PGC and pre-treatment facial weakness, and to analyze local tumor invasion of the FN. MATERIALS AND METHODS: The clinical outcomes of patients (n = 45) with PGC and pretreatment facial weakness were retrospectively analyzed. Patients had undergone 1 of 4 types of treatments: complete tumor resection, FN sacrifice with or without FN reconstruction, tumor resection with FN preservation and primary non-surgical treatments. Pathologic specimens in patients with nerve resection patients (n = 26) were reviewed to identify FN invasion by the tumor. RESULTS: Patients with PGC and facial weakness had poor clinical outcomes (44.0%, 3Y progression-free survival), and 86.7% of tumors were high-grade. In these subjects, regional or distant metastasis was an independent prognostic factor for survival. Recovery from facial weakness was suboptimal in patients with FN graft. In cases with nerve resection, 26.9% had intra-neural tumor invasion, 42.3% had perineural invasion, and 30.8% had no neural invasion in the FN. CONCLUSION: Facial weakness did not always indicate tumor invasion of the FN in PGC. Thus, the decision regarding FN resection can reasonably be further based on intraoperative findings. In cases with incomplete facial weakness and safe separation of the FN from the tumor, FN preservation offers the best functional outcomes, without compromising oncological outcomes.

Pathologic analyses of peritoneal nodules in gastric cancer patients during surgery-A single cancer center experience with diagnostic pitfalls.

BACKGROUND: Gastric carcinoma (GC) is the second most common cause of cancer-related deaths worldwide. During operations, nodular lesions of the peritoneum are often sent for frozen section (FS). For pathologists, FS of the peritoneum is challenging due to sparse and discohesive tumor cells in a fibrotic background. METHODS: To explore diagnostic accuracy and diagnostic pitfalls of FS in this setting, we retrospectively collected 252 peritoneal biopsies in cases with GC from January 2006 to May 2017 and compared corresponding permanent sections and patient prognosis. After review, 6 cases (2.4%) were discrepant: positive conversion was identified in 5 cases due to scarce tumor cells associated with severe fibrosis and inflammation; negative conversion was identified in one case due to papillary mesothelial cell proliferation masquerading as carcinoma. RESULTS: Two hundred cases were finally confirmed as positive for tumor cells. Of these, 185 (92.5%) patients died of GC, with survival times ranging from 7 to 3574 (mean 415) days after operation. Fifty-two (20.6%) cases were negative for tumor, and pathologic findings included chronic inflammation with fibrosis (N = 25: associated with previous operation, 10; idiopathic, 15) and papillary mesothelial cell proliferation (N = 9). All 5 patients with frozen diagnosis converted to positive results died of GC during follow up. A total of 19 patients with peritoneal nodules diagnosed as benign on FS died with GC (79.0%), and their survival times ranged from 87 to 3649 (mean 833) days. CONCLUSIONS: Peritoneal biopsies in patients with GC were mostly carcinoma, followed by chronic inflammation with fibrosis and papillary mesothelial cell proliferation. Deeper sections or intradepartmental consultations were helpful to reduce false negative diagnosis on FS.

MET is overexpressed in microsatellite instability-high gastric carcinoma.

BACKGROUND: MET is a tyrosine kinase receptor for the hepatocyte growth factor, and its overexpression is a poor prognostic factor in gastric carcinomas. Programmed death-ligand 1 (PD-L1) is an important biomarker of immunotherapy and is frequently positive in microsatellite instability-high (MSI-H) gastric carcinomas. In lung cancers, MET activation up-regulates PD-L1 expression. In this study, we investigated expression of MET and PD-L1 in MSI-H gastric carcinoma and the effects on prognosis. METHODS: MET and PD-L1 (SP142) immunohistochemistry was performed in 73 gastric carcinomas with MSI-H. In cases with MET overexpression, we performed fluorescent in situ hybridization (FISH). PD-L1 expression was calculated from both tumor cells (2+ and 3+ in > 10% of tumor cells was defined as PD-L1TC+) and immune cells (positive in >5% immune cells was PD-L1IC+), and also used a combined positive score (CPS; number of PD-L1 staining cells relative to all viable tumor cells; > 1 was PD-L1+). RESULTS: In 73 MSI-H gastric carcinomas, MET overexpression was observed in 11 cases (15.1%). In all 11 cases with MET overexpression,MET amplification was not found. MET overexpression was not related to any of clinico-pathological variables and PD-L1 expression. However, the PD-L1 CPS tended to be higher in tumors that were MET positive. Although MET overexpression alone was not a prognostic indicator, combined MET overexpression/PD-L1 predictive models showed that patients with MET+/PD-L1+ showed the best prognosis for overall survival as compared to other groups. CONCLUSION: MET overexpression was observed in 15% of MSI-H gastric carcinomas and was associated with high level expression of PD-L1.

Risk of high-grade malignancy in parotid gland tumors as classified by the Milan System for Reporting Salivary Gland Cytopathology.

BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (Milan System) has previously shown its diagnostic utility by categorizing the seven cytology findings in salivary gland lesions. However, there has been lack of study about the risk of high-grade malignancy in the cytology diagnosis based on the Milan System. Thus, we tried to identify the diagnostic ability of the Milan System for high-grade malignancy and to suggest an improved diagnostic approach for preoperative estimation of high-grade malignancy using the Milan System. METHODS: A total of 413 patients with parotid gland tumors, who had undergone surgical resection from 2011 to 2015 were included in the present study retrospectively. Cytopathology was reclassified according to the Milan System by two independent reviewers. The outcomes were risk of malignancy and risk of high-grade malignancy. The diagnostic performance of the Milan System category [Malignant] for detecting high-grade malignancy was calculated. RESULTS: The risk of malignancy was 83.3% and 100% in the Milan System categories [Suspicious for Malignancy] and [Malignant], respectively. Meanwhile, the risk of high-grade malignancy was 16.7% and 55.9% in these two categories. Disease-free survival of patients with high-grade malignancy was significantly worse than those with low- and intermediate-grade malignancy. Union combining the Milan System category [Malignant] with the presence of nodal metastasis suggested high-grade malignancy with an acceptable diagnostic sensitivity (0.889-0.963) and negative predictive value (0.900-0.966). CONCLUSIONS: The Milan System category [Malignant] with the presence of nodal metastasis suggested parotid gland tumors as high-grade malignancy in a pretreatment setting.

The Prognostic Impact of Synchronous Ipsilateral Multiple Breast Cancer: Survival Outcomes according to the Eighth American Joint Committee on Cancer Staging and Molecular Subtype.

BACKGROUND: In the current American Joint Committee on Cancer staging system of breast cancer, only tumor size determines T-category regardless of whether the tumor is single or multiple. This study evaluated if tumor multiplicity has prognostic value and can be used to subclassify breast cancer. METHODS: We included 5,758 patients with invasive breast cancer who underwent surgery at Samsung Medical Center, Seoul, Korea, from 1995 to 2012. RESULTS: Patients were divided into two groups according to multiplicity (single, n = 4,744; multiple, n = 1,014). Statistically significant differences in lymph node involvement and lymphatic invasion were found between the two groups (p < .001). Patients with multiple masses tended to have luminal A molecular subtype (p < .001). On Kaplan-Meier survival analysis, patients with multiple masses had significantly poorer disease-free survival (DFS) (p = .016). The prognostic significance of multiplicity was seen in patients with anatomic staging group I and prognostic staging group IA (p = .019 and p = .032, respectively). When targeting patients with T1-2 N0 M0, hormone receptor-positive, and human epidermal growth factor receptor 2 (HER2)-negative cancer, Kaplan-Meier survival analysis also revealed significantly reduced DFS with multiple cancer (p = .031). The multivariate analysis indicated that multiplicity was independently correlated with worse DFS (hazard ratio, 1.23; 95% confidence interval, 1.03 to 1.47; p = .025). The results of this study indicate that tumor multiplicity is frequently found in luminal A subtype, is associated with frequent lymph node metastasis, and is correlated with worse DFS. CONCLUSIONS: Tumor multiplicity has prognostic value and could be used to subclassify invasive breast cancer at early stages. Adjuvant chemotherapy would be necessary for multiple masses of T1-2 N0 M0, hormone-receptor-positive, and HER2-negative cancer.

MicroRNA Expression Profiles in Gastric Carcinogenesis.

Intestinal-type gastric carcinoma exhibits a multistep carcinogenic sequence from adenoma to carcinoma with a gradual increase in genomic alterations. But the roles of microRNAs (miRNA) in this multistage cascade are not fully explored. To identify differentially expressed miRNA (DEM) during early gastric carcinogenesis, we performed miRNA microarray profiling with 24 gastric cancers and precursor lesions (7 early gastric cancer [EGC], 3 adenomas with high-grade dysplasia, 4 adenomas with low-grade dysplasia, and 10 adjacent normal tissues). Alterations in the expression of 132 miRNA were detected; these were categorized into three groups based on their expression patterns. Of these, 42 miRNAs were aberrantly expressed in EGC. Five miRNA (miR-26a, miR-375, miR-574-3p, miR-145, and miR-15b) showed decreased expression since adenoma. Expression of two miRNA, miR-200C and miR-29a, was down-regulated in EGCs compared to normal mucosa or adenomas. Six miRNA (miR-601, miR-107, miR-18a, miR-370, miR-300, and miR-96) showed increased expression in gastric cancer compared to normal or adenoma samples. Five representative miRNAs were further validated with RT-qPCR in independent 77 samples. Taken together, these results suggest that the dysregulated miRNA show alterations at the early stages of gastric tumorigenesis and may be used as a candidate biomarker.

Peritumoral lymphoid cuff correlates well with lymph node enlargement in gastrointestinal schwannomas.

BACKGROUND/AIMS: To determine the incidence of regional lymphadenopathy in gastrointestinal (GI) schwannoma and to evaluate the relationship between peritumoral lymphoid cuff and lymphadenopathy. METHODS: We queried 118 GI tract schwannomas and reviewed radiologic findings, intraoperative findings, and electronic medical records of all cases for enlarged regional lymph nodes. RESULTS: Location of tumors included 85 gastric (72%), 11 colonic (9.3%), 7 esophageal (5.9%), 3 pancreatic (2.5%), 1 hepatic (0.8%), and 11 mesenteric (9.3%). The size of the tumors ranged from 0.2 to 11 cm (mean 3.8 cm). Histologically, 70.3% showed a peritumoral lymphoid cuff ranging in thickness from 0.3 to 6 mm (mean 1.6 mm). The peritumoral lymphoid cuff was significantly more frequent in gastric schwannomas (78.8%) followed by colonic (72.7%), esophageal (57.1%) and rare in other locations (p = 0.001). Of the 106 cases for which clinical or radiologic data was available for, 76 cases (71.7%) showed regional lymphadenopathy. The presence of peritumoral lymphoid cuff showed significant correlation with regional lymphadenopathy (p < 0.001) and the size of enlarged lymph nodes (p = 0.002). CONCLUSIONS: A peritumoral lymphoid cuff is frequently seen in GI tract schwannomas and correlates well with regional lymphadenopathy. However, in a significant subset (29.7%), a lymphoid cuff was not present warranting continued need for caution in the preoperative radiologic and postoperative pathologic diagnoses.

Deamination Effects in Formalin-Fixed, Paraffin-Embedded Tissue Samples in the Era of Precision Medicine.

Deamination of nucleotides causes C:G>T:A changes in formalin-fixed, paraffin-embedded (FFPE) tissue samples and produces false positives during next-generation sequencing (NGS). Uracil DNA glycosylase (UDG) helps eliminate this issue, but the effect of UDG in different tissue preparation conditions has not been rigorously studied. To investigate whether UDG can reduce false-positive single-nucleotide variant (SNV) calls, we used tumor and normal tissues from gastric adenocarcinoma patients prepared using different fixation times and pH conditions. FFPE tumor blocks >10 years were also evaluated for the comparison. We performed semiconductor-based NGS to evaluate nucleotide changes and used UDG to test deamination-related effects. Sequencing quality parameters mildly worsened with prolonged fixation time, acidic pH, and delayed fixation. SNV calls and C:G>T:A changes increased after >48 hours of fixation. In both recently prepared and old FFPE tissue blocks, UDG treatment reduced deamination-induced nucleotide changes. In the recently prepared samples, both high-quality SNVs and mean target coverage were remarkably increased on treatment with UDG. However, the quality of NGS results from old-age samples varied irrespective of UDG treatment. In conclusion, based on our findings, we believe that when performing NGS on recently embedded blocks, it is important to consider that certain poorly fixed samples may be at the risk of being deaminated, which can be corrected with UDG treatment.

NADPH Oxidase 1 and NADPH Oxidase 4 Have Opposite Prognostic Effects for Patients with Hepatocellular Carcinoma after Hepatectomy.

BACKGROUND/AIMS: Nicotinamide adenine dinucleotide phosphate oxidase (NOX)-mediated reactive oxygen species contribute to various liver diseases, including hepatocellular carcinoma (HCC). Uncertainties remain regarding the prognostic relevance of NOX1 and NOX4 protein expression in HCC. METHODS: NOX1 and NOX4 protein expression was examined by using immunohistochemistry in tumor tissue from 227 HCC patients who underwent hepatectomy. RESULTS: High immunoreactivity for NOX1 was observed in 197 (86.8%) of the 227 HCC cases and low immunoreactivity for NOX4 in 112 (49.3%). NOX1 and NOX4 proteins had opposite prognostic effects. High NOX1 expression was an independent predictor of both shorter recurrence-free survival (RFS) (p<0.01) and shorter overall survival (OS) (p=0.01). Low NOX4 expression was an independent predictor of both shorter RFS (p<0.01) and shorter OS (p=0.01). Subgroup analysis showed that, among patients with normal α-fetoprotein levels, patients with tumor size ≤5.0 cm and patients in Barcelona Clinic Liver Cancer stage A, high NOX1 expression had unfavorable effects on RFS, whereas low NOX4 expression had unfavorable effects on both RFS and OS. CONCLUSIONS: These findings demonstrated that NOX1 and NOX4 protein expression had opposite prognostic effects for HCC patients. Moreover, both proteins had prognostic value in HCC patients with normal α-fetoprotein levels or with early-stage HCC.

Expression of DBC1 is associated with poor prognosis in hepatitis virus-related hepatocellular carcinoma.

PURPOSE: Deleted in breast cancer 1 (DBC1) is a nuclear protein that was named by its deletion at a region 8p21 in some breast cancers and has been suggested as a poor prognostic indicator of various human cancers. However, the expression level of DBC1 protein and the prognostic role of DBC1 in hepatocellular carcinoma (HCC) have not been reported. METHODS: We investigated the effect of DBC1 protein expression in 199 hepatitis virus-related HCC patients. Immunohistochemical expression of DBC1 were evaluated by tissue microarray. RESULTS: High DBC1 immunoreactivity was observed in 177 (88.9%) of the 199HCC cases and was significantly associated with younger age (P=0.001), higher α-fetoprotein level (P=0.008), hepatitis B virus infection (P=0.001), and liver cirrhosis (P=0.003). High DBC1 expression showed an unfavorable effect on recurrence-free survival (RFS) (P=0.036) and tended to be an independent predictor of shorter RFS (P=0.064). High DBC1 expression did not show an unfavorable effect on overall survival (P=0.575). Five (45.5%) of 11 low grade dysplastic nodules (LGDNs), 8 (80%) of 10 high grade dysplastic nodules (HGDNs), and 10 (83.3%) of 12 early HCCs showed high DBC1 expression. The proportion of high DBC1 expression in LGDN, HGDN, early HCC, and HCC was significantly different, with a stepwise increase (P=0.0002). CONCLUSION: DBC1 protein could be a prognostic marker of shorter RFS in HCC patients after hepatectomy and human hepatocarcinogenesis was a multistep process accompanied by a stepwise increase in high DBC1 expression from LGDN, through HGDN, to HCC. Patients with high DBC1 expression can be considered candidates for adjuvant treatment after hepatectomy.

Isolated Mass-Forming IgG4-Related Cholangitis as an Initial Clinical Presentation of Systemic IgG4-Related Disease.

IgG4-related disease (IgG4-RD) may involve multiple organs. Although it usually presents as diffuse organ involvement, localized mass-forming lesions have been occasionally encountered in pancreas. However, the same pattern has been seldom reported in biliary tract. A 61-year-old male showed a hilar bile duct mass with multiple enlarged lymph nodes in imaging studies and he underwent trisectionectomy under impression of cholangiocarcinoma. Gross examination revealed a mass-like lesion around hilar bile duct. Histopathologically, dense lymphoplasmacytic infiltration and storiform fibrosis were identified without evidence of malignancy. Immunohistochemical stain demonstrated rich IgG4-positive plasma cell infiltration. Follow-up imaging studies disclosed multiple enlarged lymph nodes with involvement of pancreas and perisplenic soft tissue. The lesions have been significantly reduced after steroid treatment, which suggests multi-organ involvement of systemic IgG4-RD. Here, we report an unusual localized mass-forming IgG4-related cholangitis as an initial presentation of IgG4-RD, which was biliary manifestation of systemic IgG4-related autoimmune disease.