Real-Time Polymerase Chain Reaction for the Detection of Helicobacter pylori and Clarithromycin Resistance

Background/Aims@#Real-time polymerase chain reaction (RT-PCR) is a fast and simple method for the simultaneous detection of clarithromycin (CLR) resistance and Helicobacter pylori. We evaluated the effectiveness of RT-PCR compared to that of the rapid urease test (RUT) and assessed its value in verifying CLR resistance. @*Methods@#A total of 70 specimens with confirmed H. pylori infection in culture were enrolled and analyzed in this prospective study. All specimens were subjected to RT-PCR assay using fluorescence melting peak signals to detect H. pylori infection and CLR resistances caused by either A2142G or A2143G mutations in the 23S ribosomal RNA gene (23S rRNA). The results were compared to those of RUT and antimicrobial susceptibility culturing tests to investigate the efficacy of RT-PCR. @*Results@#Among the 70 specimens analyzed, the positivity rate was 97.1% (68/70) with RT-PCR and 82.9% (58/70) with RUT. CLR resistance (minimum inhibitory concentration >1.0 μg/mL) was confirmed in 18.6% (13/70), and fluorescence melting curve analysis showed that 84.6% (11/13) had point mutations in 23S rRNA. Ten specimens had only A2143G mutation, and one specimen contained both A2142G and A2143G mutations. @*Conclusions@#RT-PCR assay was found to be more efficient than RUT in detecting H. pylori infection and could effectively verify CLR resistance compared to the antimicrobial susceptibility culturing test. Considering the high sensitivity and accessibility of RT-PCR method, it could be used to easily detect CLR-resistant H. pylori, thus helping clinicians select suitable treatment regimen and improve the eradication rate.

Comparison of Immunohistochemistry and Direct Sanger Sequencing for Detection of the BRAF(V600E) Mutation in Thyroid Neoplasm

BACKGROUND: The BRAF V600E mutation is the most common genetic alteration identified in papillary thyroid carcinoma (PTC). Because of its costs effectiveness and sensitivity, direct Sanger sequencing has several limitations. The aim of this study was to evaluate the efficiency of immunohistochemistry (IHC) as an alternative method to detect the BRAF V600E mutation in preoperative and postoperative tissue samples. METHODS: We evaluated 71 patients who underwent thyroid surgery with the result of direct sequencing of the BRAF V600E mutation. IHC staining of the BRAF V600E mutation was performed in 49 preoperative and 23 postoperative thyroid specimens. RESULTS: Sixty-two patients (87.3%) had PTC, and of these, BRAF V600E was confirmed by direct sequencing in 57 patients (91.9%). In 23 postoperative tissue samples, the BRAF V600E mutation was detected in 16 samples (70%) by direct sequencing and 18 samples (78%) by IHC. In 24 fine needle aspiration (FNA) samples, BRAF V600E was detected in 18 samples (75%) by direct sequencing and 16 samples (67%) by IHC. In 25 core needle biopsy (CNB) samples, the BRAF V600E mutation was detected in 15 samples (60%) by direct sequencing and 16 samples (64%) by IHC. The sensitivity and specificity of IHC for detecting the BRAF V600E mutation were 77.8% and 66.7% in FNA samples and 99.3% and 80.0% in CNB samples. CONCLUSION: IHC could be an alternative method to direct Sanger sequencing for BRAF V600E mutation detection both in postoperative and preoperative samples. However, application of IHC to detect the BRAF V600E mutation in FNA samples is of limited value compared with direct sequencing.

Good Laboratory Standards for Clinical Next-Generation Sequencing Cancer Panel Tests

Next-generation sequencing (NGS) has recently emerged as an essential component of personalized cancer medicine due to its high throughput and low per-base cost. However, no sufficient guidelines for implementing NGS as a clinical molecular pathology test are established in Korea. To ensure clinical grade quality without inhibiting adoption of NGS, a taskforce team assembled by the Korean Society of Pathologists developed laboratory guidelines for NGS cancer panel testing procedures and requirements for clinical implementation of NGS. This consensus standard proposal consists of two parts: laboratory guidelines and requirements for clinical NGS laboratories. The laboratory guidelines part addressed several important issues across multistep NGS cancer panel tests including choice of gene panel and platform, sample handling, nucleic acid management, sample identity tracking, library preparation, sequencing, analysis and reporting. Requirements for clinical NGS tests were summarized in terms of documentation, validation, quality management, and other required written policies. Together with appropriate pathologist training and international laboratory standards, these laboratory standards would help molecular pathology laboratories to successfully implement NGS cancer panel tests in clinic. In this way, the oncology community would be able to help patients to benefit more from personalized cancer medicine.

Overexpression of C-reactive Protein as a Poor Prognostic Marker of Resectable Hepatocellular Carcinomas

BACKGROUND: C-reactive protein (CRP) is an acute phase reactant synthesized in the liver. CRP immunoreactivity is a feature of inflammatory hepatocellular adenomas with a higher risk of malignant transformation. A high serum CRP level denotes poor prognosis in hepatocellular carcinoma (HCC) patients. This study was conducted to determine whether CRP is produced in HCC and to assess the clinicopathologic significance of CRP expression in cancer cells. METHODS: CRP immunoreactivity was examined in treatment-naive HCCs (n=224) using tissue microarrays and was correlated with clinicopathologic parameters. The expression of CRP mRNA and protein was also assessed in 12 HCC cases by quantitative real-time polymerase chain reaction and immunoblotting. Hep3B and SNU-449 HCC cell lines were used for the analysis of CRP mRNA regulation by interleukin 6 (IL-6). RESULTS: CRP was expressed in 133 of 224 HCCs (59.4%) with a variable degree of immunoreactivity (grade 1 in 25.9%; grade 2 in 20.1%; grade 3 in 13.4%). There was an inverse relationship between grade 3 CRP immunoreactivity and cancer-specific survival (p=.0047), while no associations were found with other parameters, including recurrence-free survival. The CRP mRNA expression level was significantly higher in CRP immunopositive cases than in immunonegative cases (p<.05). CRP mRNA expression was increased in Hep3B cells, but was not detected in SNU-449 cells even after IL-6 treatment. CONCLUSIONS: We report the expression of CRP in HCC for the first time. CRP expression was associated with poor cancer-specific survival in patients with resectable HCC.

The First Case Report of Composite Bone Marrow Involvement by Simultaneously Developed Peripheral T-Cell Lymphoma, Not Otherwise Specified, and Diffuse Large B-Cell Lymphoma

No abstract available.

Peritoneal Carcinosarcoma and Ovarian Papillary Serous Carcinoma Are the Same Origin: Analysis of TP53 Mutation and Microsatellite Suggests a Monoclonal Origin

No abstract available.

Clinical and Radiological Characteristics of Ischemic Stroke in the 80 Year-Old or Older: A Single Center Study

BACKGROUND: The risk profiles and stroke presentations may differ between elderly stroke patients and their younger counterparts. The most appropriate stroke-management regime for a better outcome can only be achieved with knowledge of the characteristics of elderly stroke patients. This study compared the clinical and radiological characteristics of elderly (> or =80 years) ischemic stroke patients with those aged 80 years (40.0% vs. 63.3%; p=0.001), while their initial NIHSS score was higher (median, 4 vs. 3; p=0.033). Furthermore, an unclear stroke onset (46.4% vs. 32.8%; p=0.049) and clinicoradiological discrepancies (13.8% vs. 5.7%; p=0.044) were more common among the elderly. The proportions of subjects with stroke of undetermined cause (30.0% vs. 18.0%; p=0.019) and multiple circulation infarctions (23.3% vs. 12.6%, p=0.030) were higher among the elderly. A favorable outcome (mRS score of 0 or 1) was more common in the younger stroke patients (57.5% vs. 25.9%, p<0.0001). Multivariate analysis revealed that younger age, male gender, and initial stroke severity were significantly associated with a favorable outcome. CONCLUSIONS: These results indicate that stroke presentation in the elderly differs from that of their younger counterparts in terms of clinical and radiological variables.

Brain Abscess Associated with Pulmonary Arteriovenous Malformation

Pulmonary arteriovenous malformations (PAVMs) are induced right to left shunt and if untreated properly, those may cause severe neurological problems. A 35-year-old man who had a headache checked into an emergency room to define a brain abscess in his brain with CAT scan as well as to examine suspicious two PAVMs in his chest X-ray. Not long after the surgical management of the brain abscess, he suffered recurrent convulsive movements. We would proceed to operate his PAVMs to prevent recurrent critical neurologic complications such as brain abscess or meningitis.

Brain Abscess Associated with Pulmonary Arteriovenous Malformation / 대한간질학회지

Pulmonary arteriovenous malformations (PAVMs) are induced right to left shunt and if untreated properly, those may cause severe neurological problems. A 35-year-old man who had a headache checked into an emergency room to define a brain abscess in his brain with CAT scan as well as to examine suspicious two PAVMs in his chest X-ray. Not long after the surgical management of the brain abscess, he suffered recurrent convulsive movements. We would proceed to operate his PAVMs to prevent recurrent critical neurologic complications such as brain abscess or meningitis.

Diagnostic Utility of the JAZF1/JJAZ1 Gene Fusion in Endometrial Stromal Sarcomas and Their Histologic Variants

BACKGROUND: The diagnosis of endometrial stromal sarcoma (ESS) is often difficult in cases showing diverse histological differentiation or in undifferentiated endometrial sarcoma (UES). Recently, JAZF1/JJAZ1 gene fusion has been described as a defining feature of low-grade ESS (LGESS). However, its prevalence is variably reported, and the diagnostic utility has rarely been examined for cases showing various histological differentiation. METHODS: To test the diagnostic utility of JAZF1/JJAZ1 gene fusion in difficult cases, we compared the prevalence of the JAZF1/JJAZ1 fusion gene in LGESS with and without histological differentiation. RESULTS: The JAZF1/JJAZ1 fusion transcript was detected in 18 of 21 LGESS (85.7%), including 14 classical LGESS (93%), four LGESS with diverse histological differentiation (67%), and two with UES (28.6%). Positive cases included two LGESS with sex cord-like differentiation, one with osseous differentiation, and two UES. LGESS showing smooth muscle differentiation revealed the fusion transcript only in the classic area. Direct sequencing analysis of two LGESS revealed a previously reported breakpoint at t(7;17)(p15;q21). CONCLUSIONS: The JAZF1/JJAZ1 fusion gene was identified in a significant proportion of LGESS showing secondary histological differentiation except in cases with smooth muscle differentiation. Thus, this fusion gene may be useful to confirm the diagnosis in difficult cases of LGESS.

Angioimmunoblastic T Cell Lymphomas: Frequent Cutaneous Skin Lesions and Absence of Human Herpes Viruses

BACKGROUND: Angioimmunoblastic T-cell lymphoma (AITL) is a complex lymphoproliferative disorder and often mimics a viral infection with frequent skin involvement. Epstein-Barr virus (EBV) and human herpes virus (HHV)-6 are reported to be associated with AITL, but there are conflicting results. OBJECTIVE: We evaluated the association of EBV and HHV-6 with AITL. METHODS: We reviewed the clinical, histological and immunophenotypical features of 19 cases of AITL. Among them, 11 lymph node biopsies of AITL were examined for HHV-6, -7, and -8 by polymerase chain reaction (PCR) using virus-specific primers. In situ hybridization of EBV early region RNA (EBER) was performed and T cell receptor (TCR) gene rearrangement was also investigated in some cases. RESULTS: Among these 19 cases, maculopapular, plaque or nodular skin lesions accompanied AITL in 12 cases. Clonal TCR gene rearrangement was seen in 8/9 cases tested. EBER in situ hybridization was positive in 8 cases (57.1%). Among 7 cases with skin biopsies, five cases were consistent with cutaneous involvement of AITL, 1 case was a drug eruption, and the other case was Kaposi's sarcoma. Except a HHV-8 (+) case who also had Kaposi's sarcoma, all of these cases were negative for HHV-6, -7 and -8. CONCLUSION: Skin manifestation seems to be a cardinal component of AITL, be it in the context of presentation, progression or recurrent disease. Recognition of clinicopathological features of skin lesions in AITL as diagnostic clues should be stressed among dermatologists. The lack of HHV-6, -7 and -8 in lymph node biopsy of AITL argues against a pathogenic role for HHVs in AITL.

Microsatellite Instability in Endometrial Adenocarcinomas of Young Women

BACKGROUND: The correlation between microsatellite instability (MSI) and the prognosis of patients with endometrial carcinomas is controversial. The endometrial carcinomas in the young adult group usually have an excellent prognosis, and these tumors might have a different frequency of MSI compared with those in old women. Further, the pathogenetic mechanisms of the two groups might be different. We investigated the frequency of MSI in the endometrial cancers of patients who were under the age of 40 and we correlated the frequency with other prognostic factors. METHODS: MSI analyses were performed using 5 primers (BAT25, BAT26, D2S123, D5S346 and D17S250) and with using the genomic DNA obtained from the paraffin embedded tumor and the paired normal tissues. RESULTS: All 23 cases we examined exhibited endometrioid adenocarcinomas, and most of them were of the low international federation of gynecologists and obstetricians (FIGO) stage (stage I: 22, IIB: 1); 78% were microsatellite stable and 22% were MSI-low; an abnormal peak was present at only one marker, and any case of MSI-high was not identified. The FIGO stages of the 5 MSI-low cases were variable. CONCLUSIONS: The frequency of MSI in the endometrial cancers of young patients is not significantly different from the frequencies reported for all age groups in the previous studies, MSI-low does not seem to be related to the other poor prognostic parameters, although the number of cases we studied is insufficient to draw any firm conclusion.

Clinicopathologic Analysis of Epidermal Growth Factor Receptor Status in Non-small Cell Lung Cancer: Protein Expression, Gene Amplification and Survival Analysis

BACKGROUND: Abnormal over-expression or gene amplification of epidermal growth factor receptor (EGFR) is important in the prognosis of non-small cell lung cancer (NSCLC). We investigated the frequency of EGFR protein expression and gene amplification, and the correlation between EGFR status and survival in NSCLC. METHODS: We examined 360 cases of microarrayed NSCLC tissues for the EGFR protein expression and EGFR gene amplification using immunohistochemistry and fluorescent in situ hybridization. RESULTS: EGFR protein expression and EGFR gene amplification occurred in 110 cases (30.6%) and 24 cases (6.7%), respectively. EGFR protein expression and gene amplification were more frequent in squamous cell carcinoma than in adenocarcinoma. Differences in EGFR protein expression did not dramatically affect survival curves (p=0.740), but differences in gene amplification did (p<0.05): EGFR gene amplification was associated with a lower 5-year survival rate. CONCLUSION: EGFR protein expression and gene amplification showed moderate correlation with each other. EGFR gene amplification predicted a poor prognosis, whereas EGFR protein expression did not.

Methylation Patterns of Small Nuclear Ribonucleoprotein Polypeptide N (SNRPN) Related to the Germ Cell Differentiation of Human Germ Cell Tumors

BACKGROUND: The histogenesis and interrelationship of the various types of germ cell tumors (GCTs) have been proposed. Dysgerminoma/seminoma (D/S) is a primitive GCT that has not acquired the potential for further differentiation, whereas other types of GCTs are in a dynamic process of differentiation towards a somatic or extraembryonal direction. A primordial germ cell giving rise to a GCT undergoes a developmentally regulated erasure and resetting of imprinted genes, but changes in the imprinting pattern in GCTs as the tumor differentiates have not been well defined. We aimed to investigate the changes of the SNRPN methylation pattern between the germinomas and non-germinomatous GCTs, as compared with the somatic methylation pattern. METHODS: We used formalin-fixed paraffin-embedded tissue sections of 97 GCTs (18 Ds, 21 Ss, 17 yolk sac tumors (YSTs), 19 immature teratomas, and 22 mature teratomas). DNA methylation was evaluated after bisulfite modification, PCR amplification, and restriction enzyme digestion. RESULTS: The SNRPN methylation pattern was changed in 53/74 (71.6%) of GCTs as non-somatic patterns. There were significant differences in the methylation pattern between the germinomas and non-germinomatous GCTs, the GCTs being frequently hypo- methylated in Ds/Ss (73.3%), in contrast to the frequent hypermethylation seen in the YSTs and teratomas (47.7%, p<0.05). CONCLUSIONS: The methylation status of an imprinting gene may be involved in the mechanism causing cellular differentiation and tumorigenesis of GCTs.

Intraneural Perineurioma in the Tongue: A Case Report

We report a case of an intraneural perineurioma that developed in an unusual location, the tongue. A 16-year-old male presented with a 1 cm sized protruding submucosal mass in his tongue without any sensory or motor signs or symptoms. The mass was excised. The mucosa was intact, with an ill-defined firm mass measuring 1.0 x 0.8 x 0.6 cm in the submucosa and muscle. The cut surface of the mass was pinkish gray and fibrotic. Microscopically, the mass contained tortuous and thickened peripheral nerve bundles in the submucosa, showing onion bulb like structures. The onion bulb like structures consisted of centrally located S-100 protein positive Schwann cells surrounded by Glut-1 positive perineurial cells. The FISH study did not reveal any genetic aberrations in chromosome 22.

Efficacy of hMLH1/hMSH2 Immunohistochemical Staining as Representative Index for Microsatellite Instability Status in Sporadic Colorectal Cancer

PURPOSE: Sporadic colorectal cancer with micosatellite instability (MSI) is supposed to have a distinct molecular profile, distinct clinocopathologic feature, and a distinct prognosis. However, the test for MSI is still expensive, and a big machine is needed for routine screening. This study was performed to examine the clinicopathologic of characteristics of MSI sporadic colorectal cancer and the efficacy of immunohistochemical staining for hMLH1 and hMSH2. METHODS: Five hundred sixty nine colorectal adenocarinomas resected from September 2003 to August 2004 at Asan Medical Center were prospectively collected. FAP (familial adenomatous polyposis), HNPCC (hereditary non-polyposis colo-rectal cancer), and incomplete tests of immunohistochemical staining or MSI were excluded. The MSI status was determined by using PCR (polymerase chain reaction). A first round of immunohistochemical staining for hMLH1/hMSH2 was performed, and a second round was performed for cases showing a disparity between the two exams. The clinicopathologic variables regarding the MSI status were analyzed, and the sensitivity and the specificity of immunohistochemical staining were evaluated. RESULTS: Sporadic colorectal cancers with MSI-H were 8.4% (n=48) and were associated with age (< or = 60 years), colorectal cancer familial history, synchronous colorectal cancer, right side tumor location, and poorly differentiated or mucinous cell type. However, age, synchronous colorectal cancer, and right side tumor location were associated an the multivariate analysis. In the first round of immunohistochemical staining, no expression of hMLH1 and/or hMSH2 was obserred in 71 cases (12.5%), and the sensitivity and the specificity were 50.0% and 91.9%, respectively. After repetitive immunohistochemical staining for the 71 cases showing disagreement with the to MSI status, the sensitivity and the specificity of the second round of immunohistochemical staining were 53.3% and 97.6%, respectively. CONCLUSIONS: Sporadic colorectal cancer with MSI appears to have distinct characteristics. However, immunohistochemical staining for hMLH1 and hMSH2 is not accurate enough to be used instead of MSI.

Lymphocytic Gastritis in Helicobacter pylori-positive Gastric MALT Lymphoma: Report of Two Cases / 대한소화기학회지

Both lymphocytic gastritis and gastric mucosa associated lymphoid tissue (MALT) lymphoma are associated with Helicobacter pylori (H. pylori) infection. However, this association has not been fully elucidated. We report two cases of lymphocytic gastritis in 57-year-old male and 47-year-old female patients which were diagnosed after the H. pylori eradication to treat gastric MALT lymphoma. MALT lymphoma was successfully treated in case 1, but residual MALT lymphoma remained in case 2. During the follow-up endoscopic examinations, several elevated erosions in case 1 and irregular mucosal atrophy in case 2 were newly detected. Biopsy specimens showed marked infiltration of lymphocytes in the surface epithelium (56.6+/-15.9 intraepithelial lymphocytes (IELs)/100 epithelial cells in case 1 and 40.5+/-9.3 IELs/100 epithelial cells in case 2), which were exclusively CD8-positive T lymphocytes. These findings suggest that H. pylori infection may cause a monoclonal proliferation of B lymphocytes, leading to MALT lymphoma as well as polyclonal proliferation of T lymphocytes which subsequently infiltrated into the surface epithelium as a host immune reaction, resulting in lymphocytic gastritis.