Gastric mucin is expressed in a subset of endocervical tunnel clusters: type A tunnel clusters of gastric phenotype.

AIMS: Gastric mucin expression has been demonstrated in a group of endocervical glandular lesions. The aim of this study was to gain further insight into endocervical lesions with a gastric phenotype. METHODS AND RESULTS: Various types of tunnel clusters (TC) were examined for gastric mucin by alcian blue/periodic acid-Schiff staining and immunohistochemistry for HIK1083. Five of 34 cases of TC expressed gastric mucin defined by PAS dominant neutral mucin and immunopositivity for pyloric gland mucin. Histologically, TC expressing gastric mucin showed lobular arrangements of small to medium-sized glands composed of mucin-rich columnar cells and were classified as Flumann's type A TC. Neither type B TC nor normal endocervical glands expressed PAS dominant neutral mucin and none of them was immunopositive for pyloric gland mucin. Five patients with type A TC of gastric phenotype ranged in age from 33 to 79 years (mean 58 years) and were multiparous. Type A TC of gastric phenotype, ranging from 2 to 4 mm in maximum diameter, were incidental findings in hysterectomy specimens. CONCLUSION: Type A TC of gastric phenotype could be related to lobular endocervical glandular hyperplasia of gastric phenotype. The pathogenesis of gastric metaplasia in TC remains unclear.

[Immunohistochemical study on keratin no. 8, 18 and 19 expression of carcinoid tumors].

The purpose of this study is to evaluate keratin expression in neuroendocrine cells and carcinoid tumor of the gastrointestinal tract and lung. Neuroendocrine cells in the lung and the gastrointestinal tract reacted with low-molecular keratin strongly, but not with high-molecular keratin. The low-molecular keratin expression of carcinoid tumor in the lung and the gastrointestinal tract, which varied in degree, were identical to that of neuroendocrine cells. Keratin 8 and 18 were found abundantly in neuroendocrine tumor and carcinoid tumor of the gastrointestinal tract, and in a lesser amount in carcinoid tumor of the lung, whereas keratin 19 was found in all cases with variable amounts. Based on these results, the combination of antibodies for several types of keratin is useful for examining keratin expression as a marker of epithelium in carcinoid tumor.

A case of hepatocellular carcinoma with marked hyperfibrinogenemia.

The present report concerns a case of hepatocellular carcinoma (HCC) with marked hyperfibrinogenemia. The plasma fibrinogen level reached as high as 1,704 mg/dl. Since treatment against HCC resulted in reduction of plasma fibrinogen and PIVKA-II, an HCC marker, the hyperfibrinogenemia appears to be related to HCC. Immunohistochemically, the HCC specimen from this patient reacted strongly with antiserum to human fibrinogen, suggesting that the elevated fibrinogen was due to synthesis of this protein by the carcinoma cells, not to decreased fibrinolytic activity.

Pancreatic acinar cells in adult human islets of Langerhans.

Pancreatic acinar cells within the islets of Langerhans in human pancreas were investigated both histopathologically and electron microscopically. Acinar cells inside the islets of Langerhans were observed in all 50 adult cases investigated. Between such acinar cells and endocrine tissues, no reticular fiber was observed; they were encapsulated together instead. The acinar cells were immunostained with antiamylase similar to the "extrainsular" acinar cells and were also connected to the small pancreatic duct. Electron microscopically, intercellular junctions of the desmosomal type were found between the acinar cells and the adjacent endocrine cells. Therefore, the acinar cells within the islets of Langerhans were true acinar cells, based on the incomplete demarcation between the islets and the acinar tissue.

[Immunohistochemical study on keratin expression of uterine reserve cells].

An immunohistochemical expression in the reserve cells of the uterine cervix using monoclonal antibodies of cytokeratin which detected the different subtypes of keratin was studied. Although the reserve cells were positive for all the four cytokeratin antibodies (CAM5.2, M-20, M-888, M-630), different immunoreactivity was found as follows: CAM5.2 reacted uniformly and intensely in the cervical glands, but weak in the reserve cells. M-20 reacted similar to that of CAM5.2 in the cervical glands, but was weaker stained in the reserve cells than with CAM5.2. M-888 reacted uniformly and intensely in both the cervical glands and reserve cells. M-630 reacted only in the reserve cells, but seldom in the cervical glands. Hence, CAM5.2 and M-20, which detected No.8 and No.18 of antiserum for low-molecular weight cytokeratin, reacted more weakly in the reserve cells than in the cervical glands, and M-630, which detected No.5 and No.14 of antiserum for high-molecular weight cytokeratin, reacted uniformly and intensely in the reserve cells. That results suggested the reserve cells revealed the expression as the stratified squamous epithelium. As for cell proliferation on the cervical glands and reserve cells, the positive nuclear staining for proliferating cell nuclear antigen (PCNA) was found in both of them, especially in the cervical glands just above the reserve cells. Therefore, the reserve cells had characteristics of squamous cell epithelium and developed to metaplastic cells.