Akio Shiromizu
Oita University
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Featured researches published by Akio Shiromizu.
Surgical Endoscopy and Other Interventional Techniques | 2007
Koichi Ishikawa; Kazuhiro Yasuda; Akio Shiromizu; Tsuyoshi Etoh; Norio Shiraishi; Seigo Kitano
BackgroundThe sentinel node (SN) concept has attracted considerable attention recently for the treatment of patients with early gastric cancer (EGC). This study evaluated the feasibility of laparoscopic SN navigation achieved by means of an infrared ray electronic endoscopy (IREE) system with indocyanine green (ICG) injection in patients with EGC.MethodsLaparoscopic SN navigation was performed for 16 patients with preoperatively diagnosed EGC. After identification of SNs, routine laparoscopically assisted distal gastrectomy with lymphadenectomy was performed. Lymph nodes were examined histologically for metastasis by hematoxylin and eosin staining on one section of each node.ResultsOne or more SNs and lymphatic basins were detected in all 16 patients. The average number of SNs detected was 2.9. Lymph node metastasis was found in 2 of the 16 patients (13%). In one of these two patients, lymph node metastasis was found in SNs. In the other patient, metastasis was found in a non-SN rather than a SN, but in the same lymphatic basin. The accuracy of this detection method was 94%, and there was one false-negative case. No adverse events occurred after injection of ICG.ConclusionLaparoscopic SN navigation by means of IREE combined with ICG injection is feasible for patients undergoing laparoscopic surgery for EGC.
Annals of Surgical Oncology | 2000
Yosuke Adachi; Norio Shiraishi; Toshihiro Suematsu; Akio Shiromizu; Kimio Yamaguchi; Seigo Kitano
Background: In gastric cancer, the level and number of lymph node metastases is useful for predicting survival, and there are several staging systems for lymph node metastasis. The aim of this study was to compare the several lymph node classifications and to clarify the most important lymph node information associated with prognosis using multivariate analysis.Methods: A total of 106 patients with histologically node-positive gastric cancer treated by radical gastrectomy and extended lymph node dissection (D2, D3) were studied. The level of lymph node metastasis was categorized simply as Level I nodes (perigastric, No.1–6), Level II nodes (intermediate, No.7–9), and Level III nodes (distant, No.10–16), irrespective of the tumor location. The Level II nodes included lymph nodes along the left gastric artery, common hepatic artery, and celiac trunk.Results: Overall 5-year survival rate was 51%. Univariate analysis showed that 5-year survival rate was significantly influenced by the level of positive nodes (P < .01), total number of positive nodes (P < .01), number of positive Level I nodes (P < .01), and number of positive Level II nodes (P < .01), in addition to the tumor location (P < .05), tumor size (P < .05), gross type (P < .01), and depth of wall invasion (P < .01). Of these, independent prognostic factors associated with 5-year survival rate were the number of positive Level II nodes (0–1 vs. ≥2) (62% vs. 19%, P < .01) and the depth of wall invasion (within vs. beyond muscularis) (79% vs. 43%, P < .01).Conclusions: Among several staging systems for lymph node metastases, the number of positive Level II nodes provided the most powerful prognostic information in patients with node-positive gastric cancer. When there were two or more metastases in the Level II nodes, prognosis was poor even after D2 or D3 gastrectomy.
Surgical Endoscopy and Other Interventional Techniques | 2007
Kazuhiro Yasuda; Norio Shiraishi; Tsuyoshi Etoh; Akio Shiromizu; M. Inomata; Seigo Kitano
BackgroundLaparoscopy-assisted distal gastrectomy (LAG) is gaining acceptance for treating early gastric cancer. However, the long-term quality of life after LAG for gastric cancer is unknown. This study compared the long-term quality of life after LAG versus open distal gastrectomy (ODG) for early gastric cancer.MethodThis study included 53 patients who underwent LAG and 37 patients who underwent ODG for treatment of early gastric cancer. Quality of life was evaluated on the basis of a 22-item questionnaire that addressed food tolerance and mental and physical conditions, scored on a scale of 1–3.ResultsThe mean follow-up periods after LAG and ODG were 99.3 and 97.0 months, respectively. Although the majority of patients who had undergone LAG were consuming a normal diet and had weight loss of less than 5 kg, all 22 items and the total score of the LAG group were comparable to those of the ODG group. However, the incidence of postoperative intestinal obstruction was significantly lower in the LAG group than in the ODG group (1% vs. 13%, p < 0.05).ConclusionsLAG is equivalent to ODG with respect to long-term quality of life and is associated with a reduced incidence of postoperative intestinal obstruction.
Surgical Endoscopy and Other Interventional Techniques | 2001
Kazuya Yamaguchi; Y. Hirabayashi; Akio Shiromizu; N. Shirashi; Yosuke Adachi; Seigo Kitano
BackgroundThe mechanism underlying the development and progression of port site metastasis after laparoscopic surgery for cancer is still not understood. Hyaluronic acid secreted from mesothelial cells is thought to be a key factor that causes adhesion between cancer cells and mesothelial cells. Using a murine model of carbon dioxide (CO2) pneumoperitoneum, we evaluated the effect of exogenous hyaluronic acid on port site metastasis.MethodsBALB/c mice were injected with 5×106 human gastric carcinoma (MKN45) cells and divided into four groups treated with or without hyaluronic acid and with or without pneumoperitoneum. Three weeks later, the frequency and weight of port site metastases were determined. The effects of hyaluronic acid on tumorigenicity and tumor with MKN45 cells.ResultsPort site metastasis occurred significantly less frequently in the pneumoperitoneum-only group than in the pneumoperitoneum-with-hyaluronic-acid group (75% vs 100%, p<0.05). The port site metastatic tumor weighed significantly less in the control group (anesthesia only) than in the hyaluronic acid group (89±17 vs 288±35mg, p<0.05); it also weighed less in the pneumoperitoneum-only group than in the pneumoperitoneum-with-hyaluronic-acid group (87±24 vs 298±51 mg, p<0.05). The frequency and weight of tumors in the subcutaneous tissue were not significantly different between groups with or without hyaluronic acid injection (95% vs 90%, 331±128 vs 322±115 mg).ConclusionsUnder CO2 pneumoperitoneum, exogenous hyaluronic acid increased the frequency and weight of port site metastasis in a murine model. Hyaluronic acid secreted from mesothelial cells may be associated with the formation of port site metastasis after laparoscopic surgery for cancer under pneumoperitoneum.
Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2006
Koichi Ishikawa; Masafumi Inomata; Tsuyoshi Etoh; Akio Shiromizu; Norio Shiraishi; Tsuyoshi Arita; Seigo Kitano
Little is known about the outcomes of laparoscopic wedge resection (LWR) in comparison with conventional open wedge resection (OWR) for gastric submucosal tumor. Outcomes of 21 patients who underwent LWR (n=14) or OWR (n=7) for gastric submucosal tumor between 1993 and 2004 were investigated. We compared the short-term and long-term operative results between the 2 groups. LWR showed several advantages over OWR for gastric submucosal tumor: less blood loss, lower fever on day 1, lower analgesic usage rate, earlier first postoperative flatus and oral intake, lower leukocyte count on days 1 and 7, and lower C-reactive protein level on days 1 and 3. All patients, except 2 with histologically diagnosed high-risk gastrointestinal stromal tumor, survived during the mean follow-up period of 60 months. LWR is feasible for the management of patients with gastric submucosal tumor.
Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 1999
Toshihiro Suematsu; Akio Shiromizu; Kimio Yamaguchi; Norio Shiraishi; Yosuke Adachi; Sergo Kitano
To investigate the effects of laparoscopic surgery on the progression of cancers, it is necessary to establish a reliable and economical animal model. We describe a convenient murine pneumoperitoneal model for the study of laparoscopic cancer surgery. Under anesthesia using diethyl ether, peritoneal cavity was insufflated with gas through an intravenous catheter placed in the left lower quadrant. Syringe pump was used for continuous gas insufflation, and intraperitoneal pressure was measured. Intraperitoneal pressure increased and reached 10 cm H2O when 15 mL of CO2 gas was injected, but fell to 1 cm H2O 5 min after stopping the injection. When the continuous flow was adjusted by syringe pump between 20 and 160 mL/hour, intraperitoneal pressure was easily maintained at 8 cm H2O for >60 min. We believe that this murine model for pneumoperitoneum may be useful for the study of laparoscopic cancer surgery.
Journal of Clinical Gastroenterology | 2006
Tsuyoshi Etoh; Koichi Ishikawa; Akio Shiromizu; Kazuhiro Yasuda; Masafumi Inomata; Norio Shiraishi; Seigo Kitano
Goals We sometimes encounter residual or recurrent cancers after endoscopic mucosal resection (EMR) for early gastric cancer. The aim of the present study was to clarify the clinicopathologic characteristics of and optimal treatment for the residual cancers after EMR. Study Seventy-four patients with early gastric cancer were treated with EMR between 1994 and 2004. These patients were divided into 2 groups as follows: the curative group (n=59) and the noncurative group (n=15). The clinicopathologic data were compared between the 2 groups and the outcomes of additional therapy were reviewed. Results In the noncurative group, the tumors were located significantly frequently on the upper or middle third of the stomach compared with the curative group (P<0.05). The number of fragments in EMR was significantly larger in the noncurative group than in the curative group (P<0.05). Fifteen patients required additional treatment because of the residual cancer. Nine (75%) of 12 patients requiring surgery underwent laparoscopic surgery. Three patients were treated by endoscopic therapy. Conclusions EMR with a single fragment and with a sufficient margin is useful for the complete resection of early gastric cancer. When residual cancer occurs, laparoscopic gastrectomy may be a good alternative.
Japanese Journal of Clinical Oncology | 2013
Masafumi Inomata; Tomonori Akagi; Kentaro Nakajima; Tsuyoshi Etoh; Norio Shiraishi; Koichiro Tahara; Toshifumi Matsumoto; Tadahiko Kinoshita; Kyuzo Fujii; Akio Shiromizu; Nobuhiro Kubo; Seigo Kitano
In Western countries, the standard treatment for locally advanced rectal cancer is preoperative chemoradiotherapy followed by total mesorectal excision. However, in Japan, the treatment results without preoperative chemoradiotherapy are by no means inferior; therefore, extrapolation of the results of preoperative treatment in Western countries to Japan is controversial. We consider that survival may be improved by preoperative chemoradiotherapy with new anticancer agents as they are expected not only to decrease the local recurrence rate but also to prevent distant metastases. We are conducting a multicentre Phase II study to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy using S-1 in patients with locally advanced rectal cancer. The primary endpoint is the rate of complete treatment of neoadjuvant chemoradiotherapy. Secondary endpoints are the response rate of neoadjuvant chemoradiotherapy, short-term clinical outcomes, rate of curative resection and pathological evaluation. The short-term clinical outcomes are adverse events of neoadjuvant chemoradiotherapy and surgery-related complications. Thirty-five patients are required for this study.
Journal of Minimal Access Surgery | 2005
Toshifumi Matsumoto; Koichi Izumi; Akio Shiromizu; Kohei Shibata; Masayuki Ohta; Seigo Kitano
As a palliative bypass for unresectable gastric or periampullary cancer, gastrojejunostomy (GJ) is sometimes associated with postoperative delayed gastric emptying. We report the successful laparoscopic application of this procedure in a 78-year-old man with duodenal obstruction. Computed tomography revealed a mass in the duodenum along with multiple masses in the liver. A radiological image showed an ulcerative tumour in the third portion of the duodenum occluding the lumen. He was diagnosed as having an unresectable duodenal cancer with multiple liver metastases. He needed palliative bypass surgery. Laparoscopically, the stomach was partially divided using an endoscopic autosuture device, and end-to-side GJ was performed successfully. He was given a normal diet on the fourth postoperative day, and there was no delayed gastric emptying. Laparoscopic gastric partitioning GJ is a feasible and safe procedure to prevent postoperative delayed gastric emptying in case of malignant duodenal obstruction.
Surgery Today | 2008
Hideya Takeuchi; Yoichi Ikeda; Yoko Komori; Koichiro Tahara; Akio Shiromizu; Hirosi Hayashi; Yoichi Muto
A rare case of cecal volvulus in cerebral palsy that was preoperatively diagnosed and surgically treated without complications is herein reported. A 45-year old man, who had been treated for cerebral palsy as a result of a neonatal cerebral hemorrhage, was admitted to our hospital because of abdominal pain and vomiting. A plain abdominal X-ray film showed evidence of a huge quantity of gas in the left abdomen. Using a gastrographin enema from the colonoscope, an obstruction of the ascending colon was revealed with tapering of the lumen. A computed tomography scan showed a grossly dilated air-distended bowel in the left abdomen and soft tissue with internal architecture containing swirling strands of soft tissue and fat attenuation. An emergency laparotomy was performed. During the laparotomy the ileocecal region, which was unfixed at the retroperitoneum, was found to be twisted counterclockwise by 360° around the mesentery with the terminal ileum, thus resulting in a diagnosis of cecal volvulus. We therefore conducted an ileocecal resection. Cecal volvulus is an uncommon form of intestinal obstruction with a high mortality rate and may present considerable difficulty in diagnosis. Although cecal volvulus is rare as a cause of intestinal obstruction, it should be included in the differential diagnosis of bowel obstruction in cerebral palsy.