[Clinical and pathological characteristics of gastric adenocarcinoma of fundic gland type].

To analyze the clinical, endoscopic and pathological feature of gastric adenocarcinoma of fundic gland type (GA-FG) (18 cases) collected from Sir Run Run Shaw Hospital, affiliated with Zhejiang University School of Medicine and Taizhou Hospital of Zhejiang Province from January 2019 to July 2022. There were 18 cases of patient of GA-FG, including male 12 cases, female 6 cases, aged from 38 to 78 years old, with average age of 60.5 years old. Gastroscopy showed that bulging or flat lesions of gastric fundus were 0.2-5.5 cm in size, and the mucosal surface was smooth, redness or rough. Histologic examination showed that tumor cells were dominated by chief cells and scattered with a few oxyntic cells, formed a complex gland that anastomoses each other, and infiltrated to the submucosa. The results of immunohistochemistry showed that tumor cells were positive for the expression of mucin-6 (MUC6) and Pepsinogen 1, and partial expression of synaptophysin (Syn). GA-FG is a rare type of gastric adenocarcinoma with good differentiation, and currently only a few cases have been reported, and often easily been misdiagnosed or missed. Therefore, to master the characteristics of clinic and pathology is helpful to improve the ability of clinical pathologists in differential diagnosis.

[Reevaluation of equivocal HER2 status detected by immunohistochemistry according to the 2019 guidelines for HER2 detection].

Objective To understand the effects and clinical significance of the 2019 guidelines for the human epidermal growth factor receptor 2 (HER2) detection. Methods: According to the 2014 guidelines, 548 cases of invasive breast cancer with equivocal HER2 (2+) detected by immunohistochemistry (IHC) in Taizhou Enze Medical Center, Zhejiang Province, China from 2013 to 2019 were selected. The results of IHC and HER2/CEPl7 double-probe were reevaluated and divided into groups according to the 2019 guidelines for the comparative analysis. Results: Among the 548 IHC HER2 (2+) invasive breast cancers, the number of positive, equivocal and negative cases for HER2 were 96 (17.52%), 81 (14.78%) and 371 (67.70%), respectively, according to the 2014 guidelines. However, according to the 2019 guidelines, 10 cases (1.82%) were reclassified as IHC 1+, 2 cases in the group 2 were reclassified as negative, and all the originally equivocal cases in group 4 were reclassified as negative. Finally, the total number of positive and negative cases for HER2 were 94 (17.15%) and 454 (82.85%), respectively. Conclusions: After applying the 2019 guidelines, the number of IHC 2+ cases decreases, and the positive rate for HER2 also decreases slightly due to the reevaluation change in groups 2 and 4, leading to reclassification of the cases that were deemed equivocal according to the 2014 guidelines. In general, the new 2019 guidelines are more reasonable and easier to use.

[Gastrointestinal inflammatory myofibroblastic tumor: a clinicopathologic study].

Objective: To study the clinicopathologic characteristics, immunophenotype and ALK gene alterations of gastrointestinal inflammatory myofibroblastic tumor. Methods: Clinical data, histological features and immunohistochemical results were analyzed in 7 cases of gastrointestinal inflammatory myofibroblastic tumor at Zhejiang Province Taizhou Hospital from January 2005 to December 2016. ALK gene status was investigated by ALK fluorescence in situ hybridization. Results: There were 4 female and 3 male patients. The age of patients ranged from 1 to 72 years (median age=53 years and mean age=40 years). The tumor was located in stomach (n=4), left hemicolon (n=1), right hemicolon (n=1) and rectum (n=1). Histologically, the tumors consisted of spindle fibroblast and myofibroblast cells growing in bundles with inflammatory infiltration primarily composed of plasma cells and lymphocytes. Immunohistochemical study showed spindle tumor cells were positive for vimentin (7/7), SMA (7/7), but were negative for CD34, CKpan, CD117, DOG1, S-100 and desmin. Two cases expressed ALK protein and fluorescence in-situ hybridization revealed the presence of ALK gene rearrangement in the both cases. Conclusions: Gastrointestinal inflammatory myofibroblastic tumor is a rare neoplasm that is easily misdiagnosed. Its surgical removal is a reliable treatment. ALK may be a potential novel therapeutic target for inflammatory myofibroblastic tumor.

[Gastric glomus tumors expressing synaptophysin: clinicopathologic and immunohistochemical analyses].

Objective: To investigate the clincopathologic and immunohistochemical features of gastric glomus tumors and their differences from gastric neuroendocrine neoplasms. Methods: Six cases of gastric glomus tumors, 8 cases of glomus tumors in other sites and 7 cases of gastric neuroendocrine neoplasms were collected from the Department of Pathology, Taizhou Hospital. The clinicopathological and immunohistochemical characteristics of these tumors were analyzed retrospectively. Results: The gastric glomus tumors were located in the muscularis propria of the antrum and most cases strongly expressed synaptophysin (5/6). However, no synaptophysin expression was seen in glomus tumors of other organs.Most gastric neuroendocrine neoplasms were located in the mucosa or submucosa of the fundus and corpus. In addition to the strong expression of synaptophysin (7/7), CgA (6/7) and CD56(5/7) were strongly positive, although SMA was negative. Conclusions: Gastric glomus tumors and neuroendocrine neoplasms have similar morphological characteristics and both show strongly expression of synaptophysin. However, the location and immunohistochemical characteristics of gastric glomus tumors differ from those of the neuroendocrine neoplasms.