Shinichi Yamasaki

Immunohistochemical studies on enterokinase producing cells in the biliary tract

The activation mechanism of pancreatic enzymes refluxing into the biliary tract in the anomalous arrangement of pancreaticobiliary ducts (APBD) remains unclear. In order to elucidate this activation mechanism, an immunohistochemical examination of both bile ducts and gallbladders was carried out on 20 patients with APBD to determine whether or not enterokinase (EK) producing cells exist in the biliary tract, by employing an avidin-biotin-peroxidase complex, (ABC) method using a monoclonal antibody, hek-1. Immunoreactive EK was found in the metaplastic epithelium of the bile duct in 2 patients and the gallbladder in one, suggesting that EK production at the metaplastic epithelium is involved in an activation mechanism of pancreatic enzymes refluxing into the biliary tract. The same study was performed on the gallbladders of 62 patients without APBD, which revealed immunoreactive EK in some parts of the metaplastic epithelium of the gallbladder in 2 patients. Thus, in cases of pancreatic juice refluxing into thebiliary tract regardless of the presence of APBD, we can not refute the possibility that refluxed pancreatic enzymes may be at least partly activated by EK produced at the metaplastic epithelium.

A case of thoracic esophageal cancer undergone esophagectomy after induction chemotherapy in a Jehovah's Witness

We report the case of a 50-year-old female Jehovahs Witness with advanced esophageal cancer who underwent esophagectomy following induction chemotherapy. She visited our hospital complaining of dysphagia and was diagnosed of advanced esophageal cancer by upper endoscopy. She refused allogeneic transfusion. Induction chemotherapy was performed. Severe anemia occurred as an adverse event. A subtotal esophagectomy was performed after her anemia improved. During the surgery, a large volume of replacement fluid was injected, the blood was diluted, and intraoperative bleeding was relatively reduced. Intraoperative blood salvage was made using Cell Saver. The postoperative course were stable by using autologous blood and albumin infusion. The patient was discharged on postoperative day 27. Jehovahs Witnesses with gastrointestinal malignancies can be treated safely by performing surgical therapy based on blood replacement therapy and autologous blood transfusion.

A case of resistance to thyroid hormone diagnosed after total thyroidectomy for thyroid cancer

This is a case of a woman who was diagnosed with resistance to thyroid hormone after total thyroidectomy for thyroid cancer. Preoperative laboratory examination revealed the syndrome of inappropriate secretion of TSH, however, the patient had no thyrotoxic symptoms and no family history. Based on the results of ultrasonography and fine needle aspiration, she was diagnosed with papillary thyroid carcinoma and underwent total thyroidectomy. After the surgery, she received L-T4 therapy, but her TSH levels remained elevated. MRI was performed on the brain, but no lesions were found in the pituitary gland. Therefore, she was tested for TRβ gene, and a previously defined mutation, P453S, was detected. Ultimately, she was diagnosed as RTH and treated with L-T4. In this case, the dose of L-T4 needed to be increased to suppress her TSH levels to the normal range or less, and to prevent stimulating malignant cells. Currently, her dose of L-T4 has been increased, and her TSH levels are still lower than normal, however, she has no thyrotoxic symptoms, recurrence or metastasis of thyroid cancer. The patient is currently under careful observation regarding her circulatory and physiological status. In addition, the results of treatment still need to be monitored and evaluated.

Overexpression of IGF2 and IGF2 receptor in malignant solitary fibrous tumor with hypoglycemia: a case report

BackgroundSolitary fibrous tumor (SFT) is a prototypical mesenchymal neoplasm that induces non-islet cell tumor hypoglycemia (NICTH) due to overproduction of insulin-like growth factor 2 (IGF2). We here report the case of a malignant SFT associated with a hypoglycemia attack.Case presentationAn 81-year-old man with a large subphrenic mass presented with hypoglycemia and loss of consciousness. His serum insulin and IGF1 levels were relatively low, suggesting an excessively high serum IGF2 levels. Preoperative Western blotting of serum confirmed the overproduction of high-molecular-weight IGF2. After total tumor resection, the patient recovered from hypoglycemia without the need for further treatment. Histological examination revealed proliferation of spindle cells and frequent nuclear mitoses with STAT6 and CD34 immunoreactivity, which led to the diagnosis of malignant SFT. IGF2 was strongly upregulated in the tumor upon immunohistochemistry, consistent with the report of NICTH. In addition, the tumor expressed IGF2 receptor (IGF2R) but not IGF1R.ConclusionsThe present results indicate that the tumor co-expressed IGF2 and IGF2R. IGF2R has not previously been recognized as a tyrosine kinase receptor participating in cell signal transduction. Thus, further case series are required to determine whether IGF2R overexpression reflects the action of an unknown autocrine/paracrine system involving IGF2 for cell proliferation or for the scavenging and degradation of IGF2.