Expression of cytokeratin 7/20 and Ki67 in Helicobacter pylori-associated gastritis and intestinal metaplasia.

INTRODUCTION: Cytokeratins (CKs) have been associated with precancerous and cancerous gastric lesions in patients with Helicobacter pylori-associated chronic gastritis, making them useful for diagnosing epithelial tumors. METHODOLOGY: A retrospective study was conducted utilizing 200 formalin-fixed paraffin-embedded gastric biopsy samples collected from the lesser curvature of the stomach. Samples from the control group, patients with H. pylori infection, and patients with H. pylori-associated gastritis, with complete and incomplete intestinal metaplasia (IM) were immunostained. Monoclonal antibodies were utilized to determine the expression of CK7, CK20, and Ki-67. RESULTS: Patients infected with H. pylori had strong CK20 expression on the surface, and weak CK7 expression on the surface and deep glands; while non-specific chronic gastritis patients had weak focal CK7 expression and strong CK20 expression. The normal gastric mucosa of patients in the control group had relatively weak CK7 expression, restricted to a few cells in the neck and deep glands. CK20 showed diffuse strong reactivity on the surface. On the other hand, patients with complete IM showed a CK7 staining pattern that was either negative or weakly focal on the surface and crypts associated with diffuse surface CK20 and focal crypt staining corresponding to gastric type IM. The Ki67 proliferating index was low (≤ 15%) in H. pylori infected patients, high (> 30%) in patients with incomplete IM, and intermediate (16-30%) in patients with complete IM. CONCLUSIONS: These results indicate a significant link between the expressions of CK7/CK20 and Ki67 in patients afflicted with H. pylori and IM.

Primary mucinous tumors of the renal pelvis: Clinical, histopathological, and molecular analysis of three cases.

Primary mucinous tumors of the renal pelvis are extremely rare and pose challenges in terms of diagnosis and treatment. This study reviewed the clinical and pathological characteristics of mucinous tumors of the renal pelvis, including mucinous cystadenocarcinomas and mucinous cystadenomas. Immunohistochemical analysis was conducted in three cases, along with KRAS gene detection using the Amplification Refractory Mutation System (ARMS) method. The results revealed mucinous epithelium with acellular mucinous pools in all cases, and acellular mucinous pools were observed in the renal parenchyma and perirenal fat capsules. All tumors expressed CK20 and CDX2, and one case showed KRAS gene mutation. The study suggests that mucinous cystadenomas of the renal pelvis may exhibit borderline biological behaviors. This study is the first to report a KRAS gene mutation in a mucinous cystadenoma of the renal pelvis, offering valuable insights into the diagnosis and treatment of this rare condition.

Enhancing upper tract urothelial carcinoma diagnosis: Utility of cytokeratin 17 and CK20/CD44/p53 immunohistochemical panel.

Upper tract urothelial carcinoma (UTUC) presents diagnostic challenges due to small biopsy specimen size, poor orientation, and technical obstacles that can yield equivocal diagnoses. This uncertainty often mandates repeated biopsies to evaluate the necessity of nephroureterectomy. Prior studies have suggested cytokeratin 17 (CK17) immunostain as an adjunctive tool for diagnosing bladder urothelial neoplasia in both urine cytology and tissue biopsy specimens. We evaluated the utility of CK17 in differentiating UTUC from benign urothelium and its ability to stratify low-grade from high-grade neoplasia. Our study involved a cohort of previously diagnosed cytology (n = 29) and tissue specimens from biopsies and resections (n = 85). We evaluated CK17 staining percentage in cytology and tissue samples and localization patterns in biopsy/resection samples. Our findings showed a statistically significant distinction (p < 0.05) between UTUC and benign tissue specimens based on full thickness localization pattern (odds ratio 8.8 [95% CI 1.53-67.4]). The percentage of CK17 staining failed to significantly differentiate neoplastic from non-neoplastic cases in cytology or tissue samples. Additionally, based on prior research showing the efficacy of CK20/CD44/p53 triple panel in bladder urothelial neoplasia, we utilized tissue microarrays to evaluate if these markers could distinguish UTUC from benign urothelium. We found that CK20/CD44/p53, individually or in combination, could not distinguish urothelial neoplasia from non-neoplasia. Full thickness CK17 urothelial localization by immunohistochemistry was highly reproducible with excellent interobserver agreement and may play a supplementary role in distinguishing upper tract urothelial neoplasia from benign urothelium.

TUMOR MARKERS EXPRESSION LEVELS IN GASTRIC CANCER PATIENT'S PERIPHERAL BLOOD BY RT-PCR ASSESSMENT.

BACKGROUND: Hematological recurrence is the second most frequent cause of failure in the treatment of gastric cancer. The detection of circulating tumor markers in peripheral blood by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) method may be a useful tool to predict recurrence and determine the patient's prognosis. However, no consensus has been reached regarding the association between the tumor markers level in peripheral blood and its impact on patient survival. AIMS: To evaluate the expression of the circulating tumor markers CK20 and MUC1 in peripheral blood samples from patients with gastric cancer by qRT-PCR, and to verify the association of their expression levels with clinicopathological characteristics and survival. METHODS: A total of 31 patients with gastric adenocarcinoma were prospectively included in this study. CK20 and MUC1 expression levels were analyzed from peripheral blood by the qRT-PCR technique. RESULTS: There was no statistically significant (p>0.05) association between CK20 expression levels and clinical, pathological, and surgical features. Higher MUC1 expression levels were associated with female patients (p=0.01). There was a correlation between both gene levels (R=0.81, p<0.001), and CK20 level and tumor size (R=0.39, p=0.034). CONCLUSIONS: CK20 and MUC1 expression levels could be assessed by qRT-PCR from total peripheral blood samples of patients with gastric cancer. CK20 levels were correlated to MUC1 levels as well as to tumor size. There was no difference in disease-free survival and overall survival regarding both genetic markers expression in this series.

Clinical impact of ampulla of Vater cancer subtype classification based on immunohistochemical staining.

BACKGROUND: The histological subtype is an important prognostic factor for ampulla of Vater (AoV) cancer. This study proposes a classification system for the histological subtyping of AoV cancer based on immunohistochemical (IHC) staining and its prognostic significance. METHODS: Seventy-five AoV cancers were analyzed for cytokeratin 7 (CK7), CK20, and causal-type homeobox transcription factor 2 (CDX2) expression by IHC staining. We differentiated the subtypes (INT, intestinal; PB, pancreatobiliary; MIX, mixed; NOS, not otherwise specified) into classification I: CK7/CK20, classification II: CK7/CK20 or CDX2, classification III: CK7/CDX2 and examined their associations with clinicopathological factors. RESULTS: Classifications I, II, and III subtypes were INT (7, 10, and 10 cases), PB (43, 37, and 38 cases), MIX (13, 19, and 18 cases), and NOS (12, 9, and 9 cases). Significant differences in disease-free survival among the subtypes were observed in classifications II and III using CDX2; the PB and NOS subtype exhibited shorter survival time compared with INT subtype. In classification III, an association was revealed between advanced T/N stage, poor differentiation, lymphovascular invasion (LVI), the PB and NOS subtypes, and recurrence risk. In classification III, the subtypes differed significantly in T/N stage and LVI. Patients with the PB subtype had advanced T and N stages and a higher incidence of LVI. CONCLUSIONS: Classification using CDX2 revealed subtypes with distinct prognostic significance. Combining CK7 and CDX2 or adding CDX2 to CK7/CK20 is useful for distinguishing subtypes, predicting disease outcomes, and impacting the clinical management of patients with AoV cancer.

Immunohistochemical phenotype of colorectal carcinoma in patients with KRAS mutation and mismatch repair status.

INTRODUCTION: Aberrant expression of CK7/CK20/CDX2 is reported in percentage of colorectal carcinomas (CRC).

Virus polioma en carcinoma de células de Merkel / Polyoma virus in Merkel cell carcinoma

Introducción: El carcinoma de células de Merkel (MCC) es un tumor cutáneo maligno agresivo y de mal pronóstico. La incidencia es mayor en adultos hombres, caucásicos, con edad promedio de 70 años. Feng et al, lograron aislar un nuevo virus en muestras de este tumor, que denominaron virus polioma de células de Merkel (MCPyV). Se ha intentado establecer una relación causal entre el virus y MCC. El virus está integrado al genoma y produciría mutaciones específicas. En muestras de MCC, se ha detectado expresión de oncoproteinas virales (antígenos T) que promueven la replicación viral y tumorogénesis

Introduction: Merkel cell carcinoma (MCC) is an aggressive malignant cutaneous tumor with poor prognosis. Most cases affect elder patient with an average of 70 years of age. Feng et al isolated a new virus, the Merkel cell carcinoma polyoma virus (MCPyV). A causal relationship between MCPyV y MCC has been established. The virus is integrated in the genome and pro-duces specific mutations. MCC samples show ex-pression of viral oncoproteins (T antigens) that promote viral replication and tumorogenesis.

Clinical, Pathological, and Immunohistochemical Features of Adenomyoma in the Ampulla of Vater / 대한소화기학회지

BACKGROUND/AIMS: Ampullary adenomyoma is a benign lesion whose malignant potential has yet to be confirmed. Despite its benign nature, adenomyoma is frequently misdiagnosed as a carcinoma or adenoma and is overtreated by extensive surgery. This study was performed to analyze the clinical, pathological, and immunohistochemical features of adenomyomas in the ampulla of Vater. METHODS: Nine cases of adenomyoma in the ampulla of Vater, diagnosed in Chungbuk National University Hospital between 2008 and 2011, were enrolled in this study. We reviewed the clinical data on the symptoms, laboratory data, and radiologic findings of the abdominal computed tomography and endoscopic retrograde cholangiopancreatography. For pathological analysis, all the slides were reviewed by one pathologist, and immunohistochemical stainings with antibodies against cytokeratin 7 (CK7), cytokeratin 20 (CK20), alpha-smooth muscle actin (alpha-SMA), and Ki-67 antigen were performed. RESULTS: All the cases were CK7 positive and CK20 negative. A strong cytoplasmic expression of alpha-SMA was confirmed in all cases. The Ki-67 index was less than 1% in eight cases and 5% in one case. Four cases underwent endoscopic papillectomy, and one case received surgical ampullectomy during colorectal cancer surgery. Five cases that underwent endoscopic or surgical treatment remained symptom-free for three years. Four cases that were closely observed with repeated endoscopic examinations exhibited no interval changes in the papillary lesions. CONCLUSIONS: Endoscopic biopsy and immunohistochemistry can aid in the diagnosis of ampullary adenomyomas. Endoscopic papillectomy or surgical ampullectomy is adequate for the treatment of symptomatic ampullary adenomyomas.

A Case of Hepatic Metastasis of Gastric Hepatoid Adenocarcinoma Mistaken for Primary Hepatocellular Carcinoma / 대한소화기학회지

Gastric hepatoid adenocarcinoma is a special type of gastric carcinoma, which produces AFP. We report a case of an metastatic gastric hepatoid adenocarcinoma mistaken for primary hepatocellular carcinoma (HCC). A 72 year-old woman was transferred to our hospital for treatment of the hepatic mass. She underwent subtotal gastrectomy for gastric cancer 2 years ago. A year ago, she was diagnosed with hepatic mass and treated with transhepatic chemoembolization under the suspicion of primary HCC in other hospital. The hepatic mass looked like primary HCC on CT, and serum AFP was elevated to 18,735 IU/mL. We did the transhepatic mass biopsy and compared it to the histology of the previous gastric cancer. The results of immunohistochemical staining between them was coincident, and so it was diagnosed as a hepatic metastasis of gastric hepatoid adenocarcinoma.

A Case of Hepatic Metastasis of Gastric Hepatoid Adenocarcinoma Mistaken for Primary Hepatocellular Carcinoma / 대한소화기학회지

Gastric hepatoid adenocarcinoma is a special type of gastric carcinoma, which produces AFP. We report a case of an metastatic gastric hepatoid adenocarcinoma mistaken for primary hepatocellular carcinoma (HCC). A 72 year-old woman was transferred to our hospital for treatment of the hepatic mass. She underwent subtotal gastrectomy for gastric cancer 2 years ago. A year ago, she was diagnosed with hepatic mass and treated with transhepatic chemoembolization under the suspicion of primary HCC in other hospital. The hepatic mass looked like primary HCC on CT, and serum AFP was elevated to 18,735 IU/mL. We did the transhepatic mass biopsy and compared it to the histology of the previous gastric cancer. The results of immunohistochemical staining between them was coincident, and so it was diagnosed as a hepatic metastasis of gastric hepatoid adenocarcinoma.

Gastrointestinal Metastasis from a Primary Adenocarcinoma of the Lung Presenting with Acute Abdominal Pain / 대한소화기학회지

Symptomatic gastro-intestinal metastasis in lung cancer is extremely rare and only a few case reports have been published. Here, we report a case with lung adenocarcinoma that presented with acute abdominal pain, nausea and vomiting due to duodenum, jejunum, and colon obstruction by the gastro-intestinal metastasis. The patient underwent colonoscopy and the pathologic report was adenocarcinoma. When there are similar histologic findings in both colon and pulmonary lesion, the question is whether both lesions are primary cancer or the colon lesions are metastases from lung cancer. Microscopic examination of a conventional pathologic section was not sufficient to make this determination. Immunohistochemistry was positive for thyroid transcription factor-1 (TTF-1) and cytokeratin 7 (CK7), and negative for cytokeratin 20 (CK20) and caudal-related homeobox transcription factor-2 (CDX-2) on colon mucosa specimen. Accordingly, we used immunohistochemical marker for differential diagnosis of primary adenocarcinoma of the lung with gastro-intestinal metastasis.

Lymphoepithelioma-like Carcinoma of the Urinary Bladder

A 78-yr-old woman presented with gross hematuria for 2 weeks. On cystoscopy, a frond-like mass was observed at the bladder trigone. Transurethral resection of bladder tumor was performed for the mass. Histopathological findings showed that 90% of lesions were lymphoepithelioma-like carcinoma (LELCA) and a few lesions were non-invasive transitional cell carcinoma. On microscopy, syncytial growth pattern and indistinct cytoplasmic borders were observed with the severe infiltration of lymphoid cells. The case was followed-up for 8 months without recurrence. This is the first report of a LELCA case in Korea.