Molecular and Clinicopathological Features of Gastrointestinal Stromal Tumors in Vietnamese Patients.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are the most frequent mesenchymal neoplasms of the gastrointestinal tract. Management of GIST patients is currently based on clinicopathological features and associated genetic changes. However, the detailed characteristics and molecular genetic features of GISTs have not yet been described in the Vietnamese population. METHODS: We first identified 155 patients with primary GIST who underwent surgery with primary curative intent between 2011 and 2014 at University Medical Center at Ho Chi Minh City, Vietnam. We evaluated the clinicopathological features and immunohistochemical reactivity to p53 and Ki-67 in these patients. Additionally, KIT genotyping was performed in 100 cases. RESULTS: The largest proportion of GISTs was classified as high-risk (43.2%). Of the 155 GISTs, 52 (33.5%) were positive for Ki-67, and 58 (37.4%) were positive for p53. The expression of Ki-67 and p53 were correlated with mitotic rate, tumor size, risk assessment, and tumor stage. Out of 100 GIST cases, KIT mutation was found in 68%, of which 62 (91.2%) were found in exon 11, two (2.9%) in exon 9, and four (5.8%) in exon 17. No mutation in exon 13 was identified. Additionally, KIT mutations did not correlate with any clinicopathological features. CONCLUSIONS: The expression of Ki-67 and p53 were associated with high-risk tumors. Mutations in exon 11 were the most commonly found, followed by exon 17 and exon 9. Additionally, KIT mutation status was not correlated with any recognized clinicopathological features.

HER2 Status and Its Heterogeneity in Gastric Carcinoma of Vietnamese Patient.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) is related to the pathogenesis and poor outcome of numerous types of carcinomas, including gastric carcinoma. Gastric cancer patients with HER2 positivity have become potential candidates for targeted therapy with trastuzumab. METHODS: We investigated 208 gastric cancer specimens using immunohistochemistry (IHC), fluorescence in situ hybridization and dual in situ hybridization (ISH). We also investigated the concordance between IHC and ISH. The correlation between HER2 status and various clinicopathological findings was also investigated. RESULTS: In total, 15.9% (33/208) and 24.5% (51/208) of gastric cancers showed HER2 gene amplification and protein overexpression, respectively. A high level of concordance between ISH and IHC analyses (91.3%, κ = 0.76) was found. A significant correlation between HER2 status and intestinal-type (p < .05) and differentiated carcinomas (p < .05) was also noted. The HER2 heterogeneity was high in gastric cancers; we found 68.8% phenotypic heterogeneity and 57.6% genotypic heterogeneity. Heterogeneity in HER2 protein expression and gene amplification showed a close association with diffuse histologic type and IHC 2+. CONCLUSIONS: HER2 protein overexpression and gene amplification were detected in 24.5% and 15.9% of gastric cancer specimens, respectively. Intestinal-type showed a higher level of HER2 protein overexpression and gene amplification than diffuse type. HER2 status also showed a significant relationship with well- and moderately-differentiated carcinomas. The ratio of phenotypic and genotypic heterogeneity of HER2 was high in gastric carcinomas and was associated with HER2 IHC 2+ and diffuse histologic type.

Gastrointestinal stromal tumors

Gastrointestinal Stromal Tumor (GIST) is uncommon disease with only about 3,000 to 6,000 cases diagnosed annually. Tumors can occur in any sites in gastrointestinal tract, especially in stomach (60-70%) and small intestine (20-30%) and in large intestine and oesophagus, sometime in omentum, mesenterium, behind peritonaeum, etc. The disease is common in male from 40 to 80 years old. GIST is detected randomly during examinations such as endoscopy, X-ray or CT scan of stomach, large intestine. Tumors have two kinds of cell: lozenge cell (70%) and epithelial cell (30%). GIST is divided into 4 stages. Each stage has suitable treatments as chemical therapy, radio therapy, and targeted therapy. For metastatic GIST, tumors can be removed by surgery. The 5 years survival rate is 34% in removal tumors and is 10% in remained tumors

Gastrointestinal stomal tumor: a case report

Gastrointestinal stomal tumor is a rare mesenchymal tumor of the gastrointestinal tract. Stomach and small intestine are the most common sites. Tumors originate from interstitial cells of Cajal. The preoperative and intraoperative diagnosis is usually difficult. It is necessary to base on immunohistochemical staining with antibody CD117 for definitive diagnosis. Tumor may be benign or malignant. Surgery is the first choice, and can be associated with targeted therapy, a competitive inhibitor of specific tyrosine kinase. Postoperative recurrence is rare and commonly has no complication. It is necessary to follow up by CT scan every 6 months in the first 2 years and then every 3 years

Gastro-esophageal reflux disease

Gastro-esophageal reflux disease is a chronic disease. It develops along life, more likely recurrent, usually by some months after treatment with responses. This disease apperances in every ages, even in children and newborns, but it is more common at the age over 40 years old with the top age from 50 to 70 years old. The prevelence of disease changed from 10% to 36%. Diagnosis and treatment played an important role in preventation of complications. Pain and hemoghlobin are two complications. Causes gastro-esophageal reflux is very complex. Gastro-esophageal reflux disease is caused by many reasons and the other reasons also have different effects in each patient, even in each time on the same patient