We examined whether endocytoscopic observation of esophageal squamous cell carcinoma can replace the histologic examination of biopsy specimens. In a basic investigation, we examined 57 iodine-unstained areas in the resected specimens of the esophagus from 28 individuals. The endocytoscopic findings were graded from 0 to 3 in tandem with observations of the iodine staining. For endocytoscopic observation, we sprayed 1% methylene blue or toluidine blue as a vital dye on the surface of the esophageal mucosa, allowing 15-20 s for sufficient staining. One endoscopist observed the target lesions and decided their endocytoscopic type classification. Histological diagnoses were made by two pathologists who were unaware of the endoscopic findings. We then compared the endocytoscopic diagnosis and conventional histological diagnosis. In an in vivo investigation, we examined 71 lesions of esophageal squamous cell carcinoma. Two endoscopists diagnosed the type classification in consultation with a pathologist with regard to 'nuclear density,''nuclear abnormality,' and 'whether biopsy histology could have been omitted on the basis of endocytoscopic findings.' For the in vivo observation, we utilized XEC120U (higher magnification type [x1100]), XEC300F (lower magnification type [x450]), and XGIF-Q260EC1 (lower magnification type [x450]) instruments. In the basic investigation, among the 11 areas classified as Type 1, 10 (91%) were category 1 by the Vienna classification. Among the 39 lesions classified as Type 3, 36 (92%) were category 4 or 5. The sensitivity of endocytoscopy for malignant lesions (Vienna classification categories 4 and 5) was 94.7%, if Type 3 was considered malignant. The specificity was 84.2% according to the same criteria. In the in vivo observation, two endoscopists diagnosed more than 90% of esophageal squamous cell carcinomas as neoplasms using each type of endocytoscope. With regard to nuclear density, the pathologist considered it to be increased in 98% of cases with the XEC120U, in 94% with the XEC300F, and in 93% with the XGIF-Q260EC1. With regard to nuclear abnormality, the positivity rate was 90% with the XEC120U, 78% with the XEC300F, and 80% with the XGIF-Q260EC1. As to whether or not biopsy histology examination was considered necessary, the pathologist made a 'Yes' judgment for 84% of cases observed with the XEC120U, 66% with the XEC300F, and 67% with the XGIF-Q260EC1. Cancerous lesions diagnosed as Type 3 by both endoscopists using the XEC120U accounted for 46 (90.2%) of the 51 cases. Among these 46 cases, biopsy histology was considered unnecessary by the pathologist in 43 (93.5%). We believe that endocytoscopic observation has the potential to reduce the extent of histologic examination of biopsy specimens in cases corresponding to Types 1 and 3 of our classification.

The endocytoscopy system (ECS), adapted for clinical use in 2003, is an ultra-high-power magnifying endoscope that allows observations at the cell level. ECS is based on the technology of light-contact microscopy. The most evident use of ECS is for real-time, high-resolution diagnosis of nuclear abnormalities, mainly in patients with esophageal cancer. Up to now, three different types of ECS have been available. This diagnostic tool makes it possible to omit histological examination of biopsy samples in approximately 84% of esophageal squamous cell carcinoma, as evidence for both an increase of cell density and nuclear abnormalities is considered to be convincing proof that a lesion is malignant. Here we describe the features of ECS and the background that led to its development, and review the published literature pertaining to the observation of esophageal neoplasms using ECS.

The low percentage of specificity for the pathologist's diagnosis was considered to be attributed to the low magnification power of the GIF-Y0002. A further increase in the magnifying power of this instrument will be necessary to broaden its clinical applications.

We report a case involving leakage of cyanoacrylate (CA) to the inferior vena cava (IVC) through a gastrorenal shunt and left renal vein. A 72-year-old man with liver cirrhosis was admitted to our hospital to undergo emergency treatment for massive hemorrhage of gastric varices. Endoscopic injection sclerotherapy (EIS) using CA was performed on the varices. Radiographic fluoroscopy revealed that most of the injected CA had adhered firmly to the gastric varices, but a certain portion of the CA had flowed to the IVC through the gastrorenal shunt and left renal vein. At that point, the patient did not complain of any symptoms. However, 6 months later, he died of hepatic failure and an autopsy was performed. Histopathologic examination of the wall of the IVC and renal vein, to which CA had adhered, revealed that the CA was covered with endothelial cells of the vessel and no nearby thrombus was present. Long-term anticoagulant therapy may not be indicated in cases of leakage of CA from the gastric varices to other veins, since the leaked CA may be readily covered with endothelium without thrombus formation as in our patient. It is possible for CA to flow to the IVC and have a fatal impact. Our patient was fortunate, and for safe EIS it is important that these complications are prevented.

This clinicopathological, immunohistochemical, electron microscopic, and serological study of 382 cases (148 male, 234 female) of necrotizing lymphadenitis (NEL) in Japan confirms NEL as a self-limited disease with characteristic clinical features: high fever (38-40 °C), painful cervical lymphadenopathy (88.3 %), and leukopenia (under 4,000/mm(3)) without seasonal occurrence. Patient age varied from 5 to 80 years, but 62.8 % was younger than 30 years. There were five recurrent cases and four familial cases. In several cases, elevated serum aminotransaminase and antinuclear antibodies were found. Early in the disease, peripheral blood CD8+ cells were more abundant than CD4+ cells, but CD8+ cells decreased gradually with clinical progression, leading to an increasing ratio of CD4+/CD8+ cells during clinical course. Morphological features of involved lymph nodes are numerous CD8+ large immunoblasts, smaller CD4+ lymphocytes, plasmacytoid dendritic cells, histiocytes, and macrophages, the latter with phagocytized CD4+ apoptotic lymphocytes. Granulocytes are generally absent. These characteristics suggest that NEL is a reactive disease characterized by diploid disrupted CD4+ cells and CD8+ cells transforming to blastic cells. The etiology of the disease remains unknown, although viral infection is suggested, and its pathogenesis might include autoimmunity. Clinical characteristics and cytological and histological findings on lymph node biopsies can improve NEL diagnosis.