Hiroyuki Kikkawa

Heating of ferrite powder by an AC magnetic field for local hyperthermia

To develop materials for achieving local hyperthermia, we investigate the heating of various ferrite and metal powders by applying an external AC magnetic field. In comparison with magnetite powder, which has often been used in previous experiments, Mg-ferrite powder is more applicable for achieving local hyperthermia.

Carcinoma of the cystic duct associated with pancreaticobiliary maljunction.

We report a rare case of carcinoma of the cystic duct (CCD) associated with pancreaticobiliary maljunction (PBM). A 63-year-old man had presented with relapsing cholecystitis of 4 months, duration. Computed tomography showed a distended gallbladder: however, small mass in the cystic duct was overlooked. Endoscopic retrograde cholangiopancreatography demonstrated a long common channel (20-mm-long) and fusiform dilatation of the common bile duct, findings, which were consistent with PBM. At laparotomy, we found a papillary tumor, 20 mm in diameter, that obstructed the cystic duct. The patient underwent resection of the gallbladder and the common bile duct, lymph node dissection in the hepatoduodenal ligament, and hepaticojejunostomy. Histologic study revealed a papillary adenocarcinoma confined within the subserosal space. There was no lymphatic or perineural invasion of cancer cells. The surrounding cystic ductal mucosa showed dysplasia and hyperplasia, and the gallbladder and common bile duct showed severe inflammation. The patient has been doing well for 16 months after surgery, without tumor recurrence. This case suggests a relationship between CCD and chronic biliary inflammation caused by PBM, as in cases of gallbladder carcinoma.

Ischemia of the intestinal mucosa during cardiopulmonary bypass.

Abstract Bacterial translocation is believed to occur during cardiopulmonary bypass (CPB) because serum endotoxin concentrations rise. Intestinal ischemia during CPB, however, has never been proven directly. The condition of the intestinal mucosa during CPB was studied by measuring serum diamine oxidase (DAO) activity, an index of intestinal ischemia. Serum DAO activity, blood lactate concentration, and the arterial ketone body ratio (AKBR) were measured intraoperatively in four successive patients who underwent aortic arch replacement by the open distal anastomosis method. DAO activity rose after restoration of blood flow to the lower half of the body, and continued to rise throughout CPB. The lactate concentration also rose, mirroring the change in DAO activity, and returned to nearly normal 12 h after the operation. The AKBR decreased during CPB, with a mean minimum vale of 0.16 ± 0.07 immediately after the restoration of blood flow to the lower half of the body. The parallel rise in DAO activity and serum lactate concentration once blood flow to the lower half of the body was restored implies that ischemic injury to the mucosa of the small intestine occurs during CPB. The continued rise in these parameters throughout CPB is consistent with ongoing injury due to splanchnic hypoperfusion, as reflected in the decrease in the AKBR during the same period.

Hand-assisted laparoscopic total colorectal resection for familial adenomatous polyposis with coexisting rectal cancer

When familial adenomatous polyposis (FAP) is diagnosed in a patient, prophylactic surgery must be performed whether colorectal cancer is present or not. Operations for FAP have been performed through a large median abdominal incision or an additional perineal incision, depending on the coexistence of rectal cancer. Recently, we reported a technique of laparoscopic rectal amputation without abdominal skin incision for patients with rectal cancer to minimize postoperative cardiac and respiratory complications [6]. In this article, we report a case of laparoscopically assisted proctocolectomy with ileostomy through a minimal abdominal and perineal skin incision performed by a handassisted procedure. The purpose of combining the perineal and laparoscopic approaches is to minimize the skin incision, while retaining a rate of cure and safety equivalent to those of conventional rectal amputation, by using the advantages of laparoscopic procedures, and to facilitate postoperative recovery and improve the quality of life for relatively young patients with FAP.

Inductive Heating of Mg Ferrite Powder in High-Water Content Phantoms Using AC Magnetic Field for Local Hyperthermia

The purpose of this study is to elevate the temperature and induce necrosis tumor cells that include ferrite powder to 50–60°C by applying an alternating magnetic field. The achieved temperature is higher when compared to the conventional hyperthermia methods. We performed an experiment in which a high-water content agar phantom that was used as a quasi-tissue had 50 nm–10 μ m magnesium ferrite (MgFe2O4) dispersed in it and was then heated to a level of 190–700 kHz. The results show that the temperature of the phantom is higher for higher frequencies, larger particle sizes, and higher quantities of dispersed ferrite powder. Also, taking into account heat generation due to the magnetic powder, heat generation due to tissue metabolism, and the cooling effect of the blood flow, we solved the thermal equation related to local thermal therapy. Small differences in the distribution of ferrite powder affect the temperature increase of the tissue and the area where cell necrosis is induced.

Esophageal schwannoma treated by transthoracic esophagectomy: a case report

We report the case of a 72-year-old man with esophageal schwannoma who underwent the Ivor Lewis procedure. He suffered from dysphagia for 6 months. Esophagoscopy revealed a submucosal tumor bulging on the posterior wall 30 cm distant from the incisors. Endoscopic ultrasonography (EUS) revealed tumor located within the muscularis propria, the fourth layer of the esophageal wall. Upper gastrointestinal series showed an elevated lesion, 6 cm in diameter, on the posterior wall of the upper thoracic esophagus. These findings were suggestive of leiomyosarcoma. The area of esophagus including the tumor was resected using the Ivor Lewis procedure. The tumor was 5.5 × 4.5 × 4.5 cm in size, with a smooth surface that was elastic and firm. Histological examination revealed spindle-shaped cells with oval nuclei, and Antoni A and B types coexisted in the tumor tissue. Immunohistochemical studies yielded positive results for S-100 protein and negative results for CD34, desmin, and α-smooth muscle actin. A diagnosis of esophageal schwannoma was established. He was discharged from the hospital and has been doing well with no recurrence for 20 months after surgery.

Intragastric endoscopic mucosal resection through a temporary gastrostomy for early gastric cancer: usefulness of Buess-type endoscope

OBJECTIVE To assess the feasibility of cure of early gastric cancer by the endoscopic procedure done through a temporary gastrostomy and to use it to treat patients with various severe complications. DESIGN Prospective study. SETTING University hospital, Japan. SUBJECTS Four patients who required gastric mucosal resection for early gastric cancer. MAIN OUTCOME MEASURES Ease of the procedure, cure rate, safety under epidural anaesthesia, and outcome. RESULTS All patients had the procedure under epidural anaesthesia without pain or complaints during operation. Mean operation time was 120 minutes (60-200). Histological examination showed that the surgical margin was free of tumour in 3 of the cases. One patient who had microscopic invasion of lymph nodes subsequently underwent second-look conventional gastrectomy with lymphadenectomy. Postoperative recovery was rapid, and all patients were discharged from the hospital uneventfully. CONCLUSION This organ-preserving procedure enables good visualisation of the tumour and is useful even for high-risk patients.

Colon liver metastasis complicated with tumor thrombus in the bile duct: A case report

Highlights • Colorectal liver metastasis with bile duct tumor thrombus is rare in clinical.• Hepatectomy is a common therapeutic procedure for colorectal liver metastasis.• Colorectal liver metastasis with bile duct tumor thrombus might be a bad prognosis.