Although dexmedetomidine (DEX) is a widely used analgesic and sedative agent for endoscopic procedures, cardiovascular complications, such as bradycardia and hypotension, are frequently experienced. ...We herein report the first case of asystole-induced bradycardia due to DEX during endoscopic submucosal dissection (ESD). An 81-year-old man without cardiovascular diseases was referred for gastric carcinoma. ESD was started after administering a loading dose of DEX followed by a continuous maintenance infusion of DEX. The patient's heart rate gradually decreased, and then cardiac arrest occurred. DEX has a risk of cardiac arrest, so bradycardia should not be underestimated during sedation with DEX.
Mallory-Weiss tears (MWT) are occasionally encountered during endoscopic procedures. Esophageal endoscopic submucosal dissection (ESD) is widely performed under general anesthesia to avoid unexpected ...body movements. We present the case of a 68-year-old woman with squamous cell carcinoma. Although ESD was performed under general anesthesia, a gastric perforation at the MWT caused by gastric inflation was observed after the procedure. The perforation was closed endoscopically, and she was discharged without any sequelae. Although general anesthesia is useful for esophageal ESD, it should be noted that it can cause MWT, and in rare cases, gastric perforation, due to gastric inflation during the procedure.
Esophageal carcinomas have multidirectional differentiation abilities and different histological components have been reported. Herein, we report a case of esophageal carcinoma with four different ...differentiations. A 64-year-old man was referred to our hospital for treatment of an esophageal tumor detected during an esophagogastroduodenoscopy, which revealed an elevated lesion accompanied by a slightly depressed lesion in the middle of the esophagus. Examination of the biopsy specimen obtained from the elevated lesion revealed an adenocarcinoma, while that from the depressed lesion revealed a squamous cell carcinoma. Fluorodeoxyglucose-position emission tomography and enhanced computed tomography showed an esophageal carcinoma in the middle of the esophagus with no signs of metastasis. The preoperative diagnosis was adenosquamous cell carcinoma classified as T2N0M0 according to the TNM classification (seventh edition). Thoracoscopic esophagectomy was performed. Examination of the resected specimen revealed esophageal squamous cell carcinoma with neuroendocrine, basaloid, and ciliated glandular differentiation. Although they may be totipotent, an esophageal carcinoma consisting of four components is extremely rare. Moreover, ciliated glandular differentiation is rarely observed in the esophagus, except in individuals with bronchial esophageal duplication cysts and adenocarcinoma arises from a Barrett’s esophagus.
Pyloric gland adenoma (PGA) in the duodenum is a rare gastric phenotype duodenal neoplasm. Although heterotopic gastric mucosa in the duodenum has been recognized as a benign lesion, it is a ...potential precursor of PGA and gastric phenotype adenocarcinoma. Herein, we present a case follow-up of endoscopic and histological changes in the PGA in the duodenum from low-grade to high-grade dysplasia. PGA was considered to arise from the heterotopic gastric mucosa, because the heterotopic gastric mucosa was observed in the initial examination. It is difficult to distinguish heterotopic gastric mucosa from PGAs, both endoscopically and histologically. This increase in size may be useful for their differentiation. Therefore, endoscopists should not underestimate the growth of the heterotopic gastric mucosa compared to that in the previous examination.
Polycythemia vera is a chronic myeloproliferative disorder characterized by clonal proliferation of bone marrow progenitors. We report a case of ischemic enteritis and bowel obstruction resulting ...from polycythemia vera. A 76-year-old man was admitted to our hospital with abdominal distention. Contrast-enhanced computed tomography revealed portal vein thrombosis, superior mesenteric vein thrombosis, and dilated small intestinal loops with caliber changes at the end of the ileum. Laboratory data on admission revealed increased leukocyte, red blood cell, hemoglobin, and platelet levels. Polymerase chain reaction analysis for Janus kinase 2 V617F point mutation was positive. Intestinal obstruction due to either bowel adhesion or paralytic ileus secondary to the superior mesenteric artery and vein thrombosis caused by polycythemia vera was diagnosed. For decompression of the small intestinal obstruction, a transnasal ileus tube was placed. Despite conservative therapy, the small intestinal obstruction did not improve remarkably. Therefore, we decided to perform surgical treatment. Operative findings revealed extensive stricture in the ileum. Altogether, 30 cm of the ileum, including the known intestinal strictures, was resected. The pathological findings were consistent with ischemic enteritis. To the best of our knowledge, no case of ischemic enteritis caused by polycythemia vera has been previously reported in the literature.
Plexiform neurofibroma is mainly associated with neurofibromatosis type 1 and is seldom observed in the liver. Its occurrence in the liver without neurofibromatosis type 1 is even rarer. We report an ...extremely rare case of plexiform neurofibroma of the liver diagnosed by laparoscopic biopsy in a patient without neurofibromatosis type 1. The patient was a 35-year-old man who had neither clinical signs nor any family history of neurofibromatosis type 1. Abdominal ultrasonography, as part of a health screening, had detected a hepatic tumor. Subsequent contrast ultrasonography, computed tomography, and magnetic resonance imaging showed the tumor extending from the retroperitoneal space around the aorta to the hepatic hilum and distal portal branches in the right hepatic lobe, gallbladder, and left hepatic lobe.
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F-fluorodeoxyglucose positron emission tomography showed no abnormal accumulation. Histopathological examination of the tumor obtained laparoscopically led to a diagnosis of plexiform neurofibroma. Because the patient was asymptomatic with no features of malignancy, he was only monitored and managed. At follow-up 10 years later, computed tomography showed a decrease in tumor size. It is important to recognize that, while rare, plexiform neurofibroma can occur without neurofibromatosis type 1. We recommend follow-up instead of unreasonable surgery in such cases.
A 74-year-old woman who underwent colonoscopy was diagnosed with four laterally spreading tumors (LSTs) in the cecum and ascending and sigmoid colon, as well as type 1 and 2 cancers in the transverse ...colon. We performed endoscopic submucosal dissection (ESD) for all four LSTs and subsequent laparoscopic transverse colectomy for the transverse colon cancers. Colonoscopy performed one year later revealed newly developed type 2 cancer in the cecum and sigmoid colon at the site of the previous ESD. The patient denied a family history of colorectal cancer; therefore, recurrent colorectal cancer was attributed to tumor implantation and not hereditary colorectal cancer such as Lynch syndrome. We speculate that tumor implantation at the post-ESD ulcer site from any of the primary transverse colon cancers or LSTs could have led to cancer recurrence. To our knowledge, only a few cases of recurrent colon cancer secondary to post-ESD tumor implantation have been reported in the literature. Endoscopists who perform ESD for gastrointestinal cancers should consider the possibility of tumor cell implantation in patients with the aforementioned or similar clinical presentation.
Vitamin D3 requires the 25-hydroxylation in the liver and the subsequent 1α-hydroxylation in the kidney to exert its biological activity. Vitamin D3 25-hydroxylation is hence an essential ...modification step for vitamin D3 activation. Until now, three cytochrome P450 molecular species (CYP27A1, CYP2C11, and CYP2D25) have been characterized well as vitamin D3 25-hydroxylases. However, their physiological role remains unclear because of their broad substrate specificities and low activities toward vitamin D3 relative to other substrates. In this study, we purified vitamin D3 25-hydroxylase from female rat liver microsomes. The activities of the purified fraction toward vitamin D3 and 1α-hydroxyvitamin D3 were 1.1 and 13 nmol/min/nmol of P450, respectively. The purified fraction showed a few protein bands in a 50–60-kDa range on SDS-PAGE, typical for a cytochrome P450. The tryptic peptide mass fingerprinting of a protein band (56 kDa) with matrix-assisted laser desorption ionization/time of flight mass spectrometry identified this band as CYP2J3. CYP2J3 was heterologously expressed in Escherichia coli. Purified recombinant CYP2J3 showed strong 25-hydroxylation activities toward vitamin D3 and 1α-hydroxyvitamin D3 with turnover numbers of 3.3 and 22, respectively, which were markedly higher than those of P450s previously characterized as 25-hydroxylases. Quantitative PCR analysis showed that CYP2J3 mRNA is expressed at a level similar to that of CYP27A1 without marked sexual dimorphism. These results strongly suggest that CYP2J3 is the principal P450 responsible for vitamin D3 25-hydroxylation in rat liver.
We report a case of anaplastic pancreatic cancer showing osteoclast-like giant cells, which was preoperatively diagnosed using endoscopic ultrasound (EUS)- fine needle aspiration (FNA). A 68-year-old ...woman underwent contrast-enhanced computed tomography (CT) for evaluation of recurrent acute pancreatitis. CT revealed a hypovascular tumor involving the head of the pancreas. EUS revealed a hypoechoic mass (12×11mm) in the head of the pancreas, and EUS-FNA performed for further evaluation revealed dysplastic cells suspicious for malignancy in addition to osteoclastic giant cells. Therefore, the patient was diagnosed with anaplastic pancreatic cancer with osteoclast-like giant cells. She underwent pancreatoduodenectomy, and the resected tumor (13×12mm in size) is the smallest pancreatic tumor recorded in the Japanese literature. The tumor was classified as TS1 according to the Japanese classification system of pancreatic cancers. The patient received postoperative S-1 adjuvant chemotherapy for six months, and she continues to do well without recurrence, 4 years and 9 months postoperatively.