Hideki Kitada

Prospective study of the evaluation of the usefulness of tumor typing by narrow band imaging for the differential diagnosis of gastric adenoma and well-differentiated adenocarcinoma.

Background and Aim:  Presently, the differential diagnosis of gastric adenoma and well‐differentiated adenocarcinoma by endoscopy is very difficult. We carried out magnifying endoscopy with narrow band imaging (NBI) in lesions that required discrimination between gastric adenoma and well‐differentiated adenocarcinoma, and prospectively evaluated whether the tumor typing that we propose is useful for their differential diagnosis.

Usefulness of the DL in ME with NBI for determining the expanded area of early-stage differentiated gastric carcinoma

AIM To investigate whether magnifying endoscopy with narrow band imaging (ME-NBI) is useful for evaluating the area of superficial, depressed- or flat-type differentiated adenocarcinoma of the stomach. METHODS This procedure was performed in Saitama Medical University International Medical Center, Japanese Red Cross Kumamoto Hospital and Kitakyushu Municipal Medical Center. The subjects were 31 patients in whom biopsy findings, from superficial, depressed- or flat-type gastric lesion, suggested differentiated adenocarcinoma in the above 3 hospitals between January and December 2009. Biopsy was performed on the lesion and non-lesion sides of a boundary (imaginary boundary) visualized on ME-NBI. The results were pathologically investigated. We evaluated the accuracy of estimating a demarcation line (DL) on ME-NBI in comparison with biopsy findings as a gold standard. RESULTS The DL that could be recognized at 2 points on the orifice and anal sides of each lesion during ME-NBI was consistent with the pathological findings in 22 patients with 0-IIc lesions, 7 with 0-IIb lesions, and 2 with 0-IIb + IIc lesions, showing an accuracy of 100%. CONCLUSION The results suggest the usefulness of ME-NBI for evaluating the area of superficial, depressed- and flat-type differentiated adenocarcinoma of the stomach.

A case of pancreatic neuroendocrine tumor presenting with main pancreatic duct invasion

A 52-year-old male visited a local clinic with a subjective complaint of pain in the left side of his abdomen. Abdominal CT revealed the presence of a pancreatic body tumor. On EUS, the tumor presented hypoechoic signals with an obscure boundary, which continued from the pancreatic parenchyma to the inside of the main pancreatic duct. Abdominal contrast CT revealed a hypervascular tumor with densely stained pancreatic parenchyma. ERP findings revealed that main pancreatic duct invasion was suspected based on partial radiolucency in the duct. Distal pancreatectomy was performed, and a definitive diagnosis of pancreatic neuroendocrine tumor (WHO class G1) was made histopathologically.

Endoscopic Submucosal Dissection, a New Technique for en Bloc Resection of Large Superficial Tumor in the Esophagus

For superficial esophageal cancer, conventional endoscopic mucosal resection with cap (EMRC) has been widely prevailed for reliable and safety treatment1. Recent innovations of diagnostic endoscopy including high-resolution endoscopy, narrow band imaging (NBI), and magnified endoscopy allow detect and identify more small lesions of the GI tract, and endoscopist are forced to develop their skills for endocopic treatment. Recently, endoscopic submucosal dissection (ESD) has been developed for en bloc resection of larger superficial tumor in the GI tract than conventional EMR. In this decade, ESD has been widely accepted as a more reliable therapeutic procedure than EMR in Japan, and various devices are developed. Of the esophageal cancers, squamous cell carcinoma is the most common carcinoma in Japan, and iodine staining endoscopy has been widely used to detect esophageal SCC. Conventional EMRC has been performed for these 10 years, however, since conventional EMRC were carried out with small size cap, 12mm in diameter, there has been the risk to be piecemeal and residual lesions. Recently, newly classification of intrapapillary capillary loop pattern (IPCL) has developed for diagnose the early esophageal neoplasm, and because of these diagnostic innovation, therefore, many endoscopist are forced to remove larger en bloc resection for reliable ESD as well as gastric or colorectal lesions. Therefore, in Japan, ESD for large superficial esophageal neoplasm has been applied; however, esophageal ESD is considered as more difficult and challenging than gastric ESD, and only few studies have elucidated the technical feasibility of ESD in the esophagus. Needle knife has been used for early gastric and colorectal ESD, and it has been considered causing high complications for esophageal ESD because of its sharpness. For this reason, using other knives, some clinical case series are reported for esophageal ESD, and the safety of esophageal ESD using needle knife is still unclear. In this study, we conducted consecutive esophageal ESD with needle knife and compared EMR to evaluate safety and reliability of needle knife as esophageal ESD device.