Oka M

Mediastinoscope-assisted transhiatal esophagectomy for esophageal cancer.

Background: Transthoracic esophagectomy (TTE) is a radical strategy for treatment of esophageal cancer, and the morbidity and mortality are high. Transhiatal esophagectomy (THE) is advantageous because it avoids thoracotomy and has a shorter surgical time, but risk of intraoperative morbidity stresses the surgeon and lymph node sampling is not possible. Methods: Mediastinoscope-assited transhiatal esophagectomy (MATHE) was performed in 42 patients with esophageal cancer. Patients with superficial esophageal cancer and medical risk were included. Feasibility and efficacy of this procedure are discussed by examining short- and long-term morbidity, mortality, and survival. Results: With the mediastinoscope, esophagectomy was performed safely under direct vision. There was only a small amount of bleeding, and surgical time was short. Little morbidity and no deaths were recorded. Conclusion: MATHE is a safe and minimally invasive technique that allows direct visualization of mediastinal structures Lymph node sampling was feasible because of clear visualization of the mediastinum.

Tumour cells engineered to secrete interleukin-15 augment anti-tumour immune responses in vivo.

SummaryWe examined the effect of interleukin-15 (IL-15) gene transfer into tumour cells on the host’s anti-tumour response. In BALB/c mice IL-15 producing Meth-A cells (Meth-A/IL-15) underwent complete rejection, in a response characterized by massive infiltration of CD4+ T-cells and neutrophils. In contrast, Meth-A cells transfected with vector alone (Meth-A/Neo) grew rapidly. Moreover, rechallenged parental cells also were rejected in association with CD8+ T-cell infiltration. However, in nude mice there was no drastic difference between Meth-A/IL-15 and Meth-A/Neo cells. These results demonstrate that IL-15-secreting tumour cells can stimulate local and systemic T-cell-dependent immunity and therefore may have a potential role in cancer therapy.

Pelvic exenteration for the treatment of gynecological malignancies

Twenty-three patients undergoing pelvic exenteration for primary and recurrent gynecological malignancies from 1976 to 1994 are reported. Fifteen patients underwent total pelvic exenteration, 3 underwent anterior exenteration, and 5 underwent a posterior procedure. Eight patients had exenteration as their primary treatment (primary group), and 15 underwent exenteration as secondary treatment (recurrent group). In the primary group, two patients developed recurrence and died of it at 6 and 20 months after operation. Five patients are still being followed up and are alive without disease. Four of these 5 patients have survived more than 5 years. In the recurrent group, 12 patients were followed up and three died of complications during the early years. Seven patients died of cancer with the mean survival time of 16.6 months. The mean age, average operating time, and mean blood loss in the primary and recurrent groups were 57 vs. 53 years, 8 hours and 20 min vs. 8 hours and 10 min, and 4,120 vs. 4,190 ml, respectively. The overall cumulative 5-year survival rate was 34.7%, being 68.6% in the primary group and 16.7% in the recurrent group. It is noteworthy that the 5-year survival rate was 51.3% in the patients who had surgical margins free of disease. In conclusion, pelvic exenteration should be considered an acceptable therapeutic option when appropriately selected.

Detection of telomerase activity in peritoneal lavage fluid from patients with gastric cancer using immunomagnetic beads.

Cytologic examination of peritoneal lavage fluid is a useful predictor of peritoneal recurrence in gastric cancer. However, this technique is not overly sensitive and requires special abilities in the cytologist. In this study, telomerase activity was used to detect free cancer cells in peritoneal lavage fluid from patients with gastric cancer. In the first part, 12 lavage-fluid samples obtained from 12 patients with gastric cancer were analysed using the conventional telomeric repeat amplification protocol (TRAP) assay. Three of five patients with early gastric cancer had positive telomerase activity. These false-positive results may have been due to lymphocyte contamination. Furthermore, polymerase chain reaction inhibitors were also detected in the lavage-fluid samples. Therefore, we developed a novel method for elimination of haematopoietic cell and Taq polymerase inhibitors to increase the accuracy of the TRAP assay using immunomagnetic beads, which bind to most normal and neoplastic human epithelial cells. Telomerase activity was found in 10 of 20 (50%) lavage-fluid samples from patients with serosal or subserosal invasion. Cytologic examination was positive in nine of 20 (45%) samples. Both the telomerase activity and cytology were negative in all 14 patients without serosal or subserosal invasion. These results suggest that the TRAP assay combined with immunomagnetic beads might be useful for detection of free cancer cells in the peritoneal space in gastric cancer without the aid of an experienced cytologist.

A nationwide survey of opsoclonus–myoclonus syndrome in Japanese children

BACKGROUND Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disease characterized by opsoclonus, myoclonus, ataxia, and behavioral changes. The aim of our study was to investigate the epidemiological characteristics of OMS in Japan and to clarify the association between therapy and prognosis. METHODS We retrospectively collected the data from 626 Japanese medical institutions from 2005 to 2010, and analyzed the clinical features of pediatric patients with OMS based on the data. RESULTS In this survey, there were 23 patients (10 males and 13 females). The median ages at the disease onset and the time of study were 16.5 months (range: 11-152 months) and 54 months (range: 24-160 months), respectively. The principal symptoms were opsoclonus (23 patients, 100%), myoclonus (21 patients, 91.3%), and ataxia (23 patients, 100%). The related factors were neuroblastoma (10, 43.5%), infection (9, 39.1%), and immunization (2, 8.7%). The treatments for OMS were included intravenous immunoglobulin (17, 73.9%), methylprednisolone pulse (13, 56.5%), oral prednisolone (12 patients, 52.2%), and chemotherapy and/or operation for the underlying tumors (6, 26.1%), and rituximab (2, 8.7%). Complete remissions were obtained in 35.3%, 23.1%, 33.3%, 66.7%, and 100% of these treatments, respectively. At the latest follow-up period, 8 (34.8%) and 17 patients (73.9%) showed neurological sequelae of motor and intellectual functions, respectively. Patients whose treatment was started more than 30 weeks after the disease onset suffered from the severest neurological sequelae (OMS severity 4) more frequently than those less than 30 weeks (p=0.022). CONCLUSION The annual incidence of OMS was estimated to be 0.27-0.40 cases per million in Japanese children. More than 70% of OMS patients had neurological sequelae, especially intellectual function. Early effective treatments within 30 weeks after the onset may be required to prevent the serious neurological outcome.

Laparoscopic resection of large leiomyomas of the gastric fundus

Two patients with a large leiomyoma arising from the gastric fundus underwent laparoscopic resection. In case 1, the tumor was located in the anterior wall of the gastric fundus. To prevent stenosis and preserve the volume of the residual stomach, intragastric resection was adopted. The tumor was markedly and resected with laparosonic coagulating shears with a 1-cm safety margin. In case 2, a large tumor was detected in the duodenal bulb. Serious hemorrhage mandated emergency resection. The tumor originated from the posterior wall of the fundus. Attempts at reduction with the forceps failed. Reduction by digital manipulation via laparoscopic port sites was successful. An endostapler was used to resect the tumor and close the anterior wall. Both patients recovered uneventfully.

Effects of the time interval between clamping and linear stapling for resection of porcine small intestine

BackgroundAlthough a wait of several seconds after clamping is recommended when an automatic stapler is used to achieve adequate hemostasis, this wait has not been experimentally clarified.MethodsTo determine whether waiting is necessary between clamping and firing of a linear stapler, this study evaluated the number of staple line bleeding points and histologic changes in stapling sites of porcine small intestine (n = 46). It also assessed the ratio of dry to wet tissue weight (DW ratio) (n = 20) of porcine small intestine clamped between the prongs of a linear stapler. The sites were studied separately as follows: no wait with a four-row device (n = 12), no wait with a six-row device (n = 11), wait with a four-row device (n = 12), and wait with a six-row device (n = 11). The linear stapler was fired immediately after clamping in the no wait group and 1 min after clamping in the wait group.ResultsThe mean number of staple line bleeding points in 2 to 5 min with the six-row device and in 3 to 5 min with the four-row device after firing were significantly less in the wait group than in the no wait group using the same device (p < 0.05). Cross sections of staple lines showed a higher frequency of mucosal cutting in the no wait group than in the wait group for both the four-row and the six-row devices (both significant at p < 0.01). Although the mean wet tissue weights of anastomotic sites did not change in either group, the mean DW ratio was significantly less in the wait group than in the no wait group (p < 0.01).ConclusionsA 1-min interval after clamping decreases the amount of clamped tissue. Waiting may thus be necessary to reduce bleeding from stapling sites, which may be related to a decrease in mucosal cutting.

New Technique for Inducing Reversible Obstructive Jaundice in the Rat

We present a new animal model of reversible obstructive jaundice, in which two polyethylene tubes were inserted into the common bile duct, one towards the liver and the other towards the duodenum. The ends of the tubes were tunneled subcutaneously and tied shut to establish obstructive jaundice. Biliary drainage was achieved without a second laparotomy by connecting the tubes with a 1-cm segment of a 24-gauge needle. Serum concentrations of total bilirubin (TB), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), alkaline phosphatase (ALP), and albumin (Alb.) were measured before and after obstruction and decompression. TB, GOT, GPT and ALP increased and Alb. decreased 7 days after the onset of biliary obstruction. All values normalized 14 days after biliary drainage at the latest. Our model is reproducible and allows for evaluation of biliary decompression. Unlike previous models, it can be used for long-term investigation of chronic obstructive jaundice.

Effect of Cautery with Irrigation Forceps on the Remnant Liver after Hepatectomy in Rats

Monopolar cautery with irrigation forceps (CIF) was devised for use in liver resection that does not require occlusion of inflow to the remnant liver. However, a high power output is required to divide the hepatic parenchyma which boils the irrigation water. This study was performed to investigate the effects of using CIF on the hepatic parenchyma. Histologic and biochemical examination was performed in rats which had undergone hepatectomy using the CIF, irrigating bipolar (IB), Pringle’s maneuver with blunt dissection (group P), or a sham operation. A greater cautery distance was obtained with the CIF than the IB. There was no significant difference in the remnant liver function after the 1st postoperative day in any of the groups. CIF is an effective instrument for anatomic or nonanatomic hepatic resection.

Tau protein concentrations in the cerebrospinal fluid of children with acute disseminated encephalomyelitis

BACKGROUND Acute disseminated encephalomyelitis (ADEM) is clinically characterized by the acute onset of neurological symptoms after a viral infection or immunization, and is thought to represent an autoimmune disease directed against myelin. Tau protein is a phosphorylated microtubule-associated protein, primarily located in neuronal axons. Increased levels of tau protein in cerebrospinal fluid (CSF) are found in various pathological conditions. METHODS We used tau protein as a marker of axonal damage and examined its concentration in the CSF of 27 children with ADEM. RESULTS CSF tau protein concentration in children with ADEM was significantly higher than that in the CSF of control subjects (P=0.008). There were no significant differences in CSF tau protein concentrations in the ADEM patients with and without encephalopathy. The CSF tau protein concentration in patients with partial lesion resolution in follow-up brain MRI was significantly higher than in patients with complete lesion resolution (P=0.014). CONCLUSIONS In conclusion, we demonstrated that CSF tau protein concentration was significantly increased in ADEM patients. Our findings suggest that axonal damage may occur in addition to demyelination in children with ADEM.