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Seigo Kitano

Publications and source records attributed to Seigo Kitano.

At least 19 recordsLinked to original sources

A multicenter study on oncologic outcome of laparoscopic gastrectomy for early cancer in Japan.

BACKGROUND: Laparoscopic surgery for gastric cancer is technically feasible, but it is not widely accepted because it has not been evaluated from the standpoint of oncologic outcome. We conducted a retrospective, multicenter study of a large series of patients in Japan to evaluate the short- and long-term outcomes of laparoscopic gastrectomy for early gastric cancer (EGC). METHODS: The study group comprised 1294 patients who underwent laparoscopic gastrectomy during the period April 1994 through December 2003 in 16 participating surgical units (Japanese Laparoscopic Surgery Study Group). The short- and long-term outcomes of these patients were examined. RESULTS: Distal gastrectomy was performed in 1185 patients (91.5%), proximal gastrectomy in 54 (4.2%), and total gastrectomy in 55 (4.3%); all were performed laparoscopically. The morbidity and mortality rates associated with these operations were 14.8% and 0%, respectively. Histologically, 1212 patients (93.7%) had stage IA disease, 75 (5.8%) had stage IB disease, and 7 (0.5%) had stage II disease (the UICC staging). Cancer recurred in only 6 (0.6%) of 1294 patients treated curatively (median follow-up, 36 months; range, 13-113 months). The 5-year disease-free survival rate was 99.8% for stage IA disease, 98.7% for stage IB disease, and 85.7% for stage II disease. CONCLUSIONS: Although our findings may be considered preliminary, our data indicate that laparoscopic surgery for EGC yields good short- and long-term oncologic outcomes.

Adenocarcinoma↗

Receptor activator of nuclear factor-kappaB ligand (RANKL) expression in hepatocellular carcinoma with bone metastasis.

BACKGROUND: Although receptor activator of nuclear factor-kappaB ligand (RANKL) seems to be involved in the development of bone metastases in several malignant tumors, its role in hepatocellular carcinoma (HCC) has not been investigated. METHODS: We retrospectively examined the immunohistochemical expression of RANKL in formalin-fixed, paraffin-embedded resected specimens obtained from 96 patients with HCC with (n = 16) and without (n = 80) bone metastases. In addition, tumor RANKL mRNA expression was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) in five selected patients. We analyzed the relationship between RANKL expression level, bone metastasis development, and survival rate of patients with HCC after hepatic resection. RESULTS: Of the 96 patients with HCC, serum hepatitis C virus antibody was detected in 43.5% of patients and hepatitis B surface antigen in 29.5% of patients. Thirty-three patients (36.5%) also had liver cirrhosis. Immunohistochemical analysis showed that RANKL protein was present in 10 (62.5%) of 16 patients with HCC with bone metastasis compared with 21 (26.3%) of 80 patients with HCC without bone metastasis; we found that RANKL expression was statistically significantly correlated to bone metastasis development (P < .01). RANKL mRNA expression was confirmed by RT-PCR in patients positive for RANKL protein expression by immunohistochemistry. The 5-year cancer-related (P < .01) and disease-free survival (P < .01) rates after hepatic resection were statistically significantly worse in patients positive for RANKL expression compared with RANKL-negative patients. CONCLUSIONS: Some HCC cells produced the crucial bone resorption regulator RANKL. Because RANKL modulates bone turnover, its presence would have profound implications for the establishment and development of bone metastases.

Adult↗

Decreased growth rate of lung metastatic lesions after splenectomy in mice.

BACKGROUND: The effect of splenectomy on hematogenous metastases of malignant tumors remains controversial. The aim of this study was to clarify the effect of splenectomy on hematogenous metastases in an animal model. METHODS: Colon 26 cancer cells were inoculated into the lateral tail vein of 90 mice. The mice were then assigned to a splenectomy group or a control group. Lung weight, number of lung metastases, size of metastatic nodules, and serum vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) levels after the surgical procedure were measured and compared between the two groups. RESULTS: The lung nodules were significantly smaller in the splenectomy group than in the control group. In both groups, the serum VEGF levels increased on day 1 and then decreased. The serum VEGF levels on day 5 were significantly lower in the splenectomy group than in the control group. The serum bFGF levels were significantly lower in the splenectomy group than in the control group on days 1 and 5. Immunohistochemical study showed that bFGF was produced by reticuloendothelial cells of the spleen. CONCLUSION: The growth rate of hematogenous metastatic lesions appears to decrease after splenectomy and may be associated with decreases in serum levels of VEGF and bFGF induced by splenectomy.

Adenocarcinoma↗

Length of laparotomy incision and surgical stress assessed by serum IL-6 level.

BACKGROUND: Because surgical stress is thought to have an effect on morbidity, mortality, and remnant tumour progression after surgery, diminishing surgical stress is important. The purpose of this study was to assess in a murine model whether the length and type of laparotomy incision influence surgical stress. METHODS: Serum IL-6 concentrations were measured sequentionally in 220 male BALB/c mice who were assigned to different basic laparotomies, (1-cm versus 2-cm versus 3-cm laparotomy with or without caecal resection), other types of laparotomy (3-cm, 1-cm x 3, 3-cm transverse, 3-cm laparotomy with rapid closure), or 3-cm skin incision with or without laparotomy. The serum level of IL-6 was measured by ELISA. RESULTS: Serum IL-6 levels at 3 and 6h after surgery were significantly higher in the 3-cm laparotomy group (1,680+/-802pg/ml and 1,066+/-507pg/ml, respectively), than in the 1-cm laparotomy group (797+/-427pg/ml and 515+/-212pg/ml, respectively). When caecal resection was added, the serum IL-6 level at 6h was significantly higher in the 3-cm laparotomy group (2,844+/-134pg/ml) than in the 1-cm laparotomy group (2,200+/-379pg/ml). Although the type of laparotomy incision was not associated with the serum level of IL-6, the serum IL-6 level after midline skin incision without laparotomy (245+/-142pg/ml) was significantly lower than that after 3-cm laparotomy (1,680+/-802pg/ml). CONCLUSIONS: The length of laparotomy incision was correlated with the serum level of IL-6 in a murine model. The surgical stress related to abdominal procedures might be decreased when laparotomy wounds are kept as small as possible.

Animals↗

Improved long-term survival after liver resection for hepatocellular carcinoma in the modern era: retrospective study from HCV-endemic areas.

INTRODUCTION: It remains unclear whether recent progress in perioperative management and treatment for recurrent hepatocellular carcinoma (HCC) has improved patient outcomes in hepatitis C virus-endemic areas. METHODS: The clinicopathologic and follow-up data of 218 consecutive HCC patients who underwent curative resection between 1982 and 2003 were analyzed. Patients were assigned to one of two groups: before 1992 (early group; n=82) and 1992 and later (late group; n=136). Factors influencing survival rates were investigated by multivariate analysis. The effects of the period during which the hepatic resection was done on the patients' outcome were examined with respect to tumor size. RESULTS: The 5-year cancer-related and disease-free survival rates were 51.4% and 20.4%, respectively. The late group showed better 5-year cancer-related survival than the early group (64.1% vs. 33.8%), but disease-free survival did not differ significantly between the groups. On multivariate analysis, the period of the hepatic resection was identified as an independent prognostic factor for cancer-related survival (relative risk 0.70, P<0.01) but not disease-free survival. There were no differences in the cancer-related and disease-free survival rates between the two groups for patients with tumors 50 mm, both cancer-related and disease-free survival rates were better in patients in the late group. CONCLUSIONS: During the past two decades, improvements in the treatment of recurrent HCC tumors have contributed to controlling large HCCs but not to controlling the multicentric development of HCCs. It may be important to control multicentric recurrence of HCC to improve patient survival in areas where the hepatitis C virus is endemic.

Adult↗

Laparoscopic gastrectomy with lymph node dissection for gastric cancer.

Since 1991, laparoscopic surgery has been adopted for the treatment of gastric cancer, and it has been performed worldwide, especially in Japan and Korea. We reviewed the English-language literature to clarify the current status of and problems associated with laparoscopic gastrectomy with lymph node dissection as treatment for gastric cancer. In Japan, early-stage gastric cancer (T1/T2, N0) is considered the only indication for laparoscopic gastrectomy. As yet, there is little high-level evidence based on long-term outcome supporting laparoscopic gastrectomy for cancer, but reports have provided level 3 evidence that the procedure is technically safe, and that it yields better short-term outcomes than open surgery; that is, recovery is faster, hospital stay is shorter, there is less pain, and cosmesis is better. However, investigation into the oncological outcome of laparoscopic gastrectomy as treatment for cancer is lacking. To establish laparoscopic surgery as a standard treatment for gastric cancer, multicenter randomized controlled trials to compare the short- and long-term outcomes of laparoscopic surgery versus open surgery are necessary.

Carcinoma↗

Prognostic value of preoperative peripheral blood monocyte count in patients with hepatocellular carcinoma.

BACKGROUND: The prognostic significance of the leukocyte subsets in peripheral blood has not yet been investigated in hepatocellular carcinoma patients. We sought to clarify the prognostic value of preoperative peripheral blood leukocyte subset counts, especially the absolute monocyte count, in HCC patients who have undergone hepatic resection. METHODS: We retrospectively examined the relation between the preoperative absolute number of peripheral monocytes and clinicopathologic factors or long-term prognosis in 198 patients with hepatocellular carcinoma who underwent curative resection. RESULTS: Univariate analysis indicated a significantly worse 5-year disease-free survival rate in patients with a peripheral blood monocyte count > 300/mm(3) (14.8%) than in patients with a count < or = 300/mm(3) (29.2%). There were no significant differences between patients in disease-free survival based on the lymphocyte or neutrophil count. According to multivariate analysis, preoperative peripheral blood monocyte count > 300/mm(3), alpha-fetoprotein level > 100 ng/mL, aspartate aminotransferase level > 100 IU/mL, and presence of microvascular invasion were independent risk factors for disease-free survival of less than 5 years. The peripheral blood monocyte count was higher in patients of male sex or those with a noncirrhotic liver, microvascular invasion, major hepatic resection, older age (>65 years), large tumor (> or =50 mm), or increased platelet count (>100,000/mm(3)) than in patients without these characteristics. CONCLUSIONS: Our findings indicate that the preoperative absolute count (>300/mm(3)) of peripheral blood monocytes may be related to tumor progression and that it is an independent risk factor for recurrence of hepatocellular carcinoma after resection. Postoperative adjuvant chemotherapy might be necessary in patients with elevation of the preoperative absolute count of peripheral blood monocytes.

Adult↗

Laparoscopic surgical resection for early gastric cancer.

This paper provides an overview of the current status of laparoscopic resection for early gastric cancer. According to many case-control studies, laparoscopic gastrectomy is feasible and safe, and in comparison with conventional open gastrectomy is associated with less pain, a quicker recovery of gastrointestinal function, and a better postoperative quality of life, with no negative influence on survival. Large randomized controlled trials of laparoscopic versus open gastrectomy are needed to establish the future role of laparoscopic surgery in the treatment of patients with gastric cancer.

Gastrectomy↗

Long-term outcome of laparoscopic wedge resection for gastric submucosal tumor compared with open wedge resection.

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.

Aged↗

Laparoscopic splenectomy in patients with inflammatory pseudotumor of the spleen: Report of 2 cases and review of the literature.

We report 2 cases of splenic inflammatory pseudotumor treated by laparoscopic splenectomy. The first patient was a 58-year-old woman who complained of constipation. Computed tomography (CT) showed a well-demarcated mass that measured 4 cm in diameter and was not enhanced. She underwent laparoscopic splenectomy under a preoperative diagnosis of hemangioma. The final histopathologic diagnosis was inflammatory pseudotumor. The second patient was a 29-year-old man who complained of abdominal pain. Computed tomography revealed a demarcated splenic tumor that measured 3 cm in diameter and was not enhanced. Laparoscopic splenectomy was performed. The pathologic and operative diagnoses were both inflammatory pseudotumor. In both cases, the postoperative course was uneventful, and the postoperative hospital stays were 10 and 11 days. Preoperative diagnosis of a splenic inflammatory pseudotumor is very difficult. However, laparoscopic splenectomy is safe and beneficial treatment for this tumor and should be performed in cases in which it is diagnosed.

Adult↗

Clinicopathologic features and treatment of residual early cancers after endoscopic mucosal resection of the stomach.

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.

Aged↗

Chemokine receptor CCR6 as a prognostic factor after hepatic resection for hepatocellular carcinoma.

BACKGROUND AND AIMS: Chemokines and their receptors have recently been shown to have major roles in cancer metastasis. The aim of this study was to determine whether the interaction between chemokine receptor 6 (CCR6) and its ligand, macrophage inflammatory protein-3 alpha (MIP-3alpha), correlates with metastasis of hepatocellular carcinoma (HCC). METHODS: To observe the reaction of CCR6 expressed cancer cells to MIP-3alpha stimulation, chemotactic and actin polymerization assays for both CCR6 high cells (HepG2) and CCR6 low cells (MCF-7) were performed. CCR6 mRNA levels in tumor specimens from 30 HCC patients were quantified by real-time polymerase chain reaction. Patients were classified into two groups, high (>or= 20 copies; n=10) CCR6 and low (<20 copies; n=20) CCR6 on the basis of CCR6 expression, and the groups were compared with respect to clinicopathological features. RESULTS: When HepG2 cells (CCR6 high) were stimulated with MIP-3alpha, they migrated in a dose-dependent manner, and formation of pseudopodia was observed. These phenomena were not observed in the CCR6 low cells. The incidence of intrahepatic metastasis was higher in the high CCR6 expression group than in the low CCR6 expression group (P<0.05). Disease-free survival was significantly poorer in the high CCR6 expression group than in the low CCR6 expression group (P<0.05). CONCLUSIONS: It was indicated that CCR6 might be associated with intrahepatic metastasis of HCC and might be able to become one of the prognostic factor after hepatic resection for HCC.

Aged↗

Expression of endothelin receptors in the gastric mucosa of portal hypertensive rats.

BACKGROUND: Portal hypertensive gastropathy is an abnormal circulatory state in gastric mucosa with vascular dilatation due to portal hypertension. The aim of the present study was to evaluate expression of endothelin receptors and their roles in the portal hypertensive gastric mucosa. METHODS: Portal hypertensive rats were generated by staged portal vein occlusion. Expression of endothelin-A receptor and endothelin-B receptor mRNA was examined by reverse transcriptase-polymerase chain reaction, and protein were examined by immunohistochemistry. The changes of mucosal microcirculation by endothelin receptor antagonists were measured with in vivo microscope. RESULTS: Expression of endothelin-A receptor mRNA was increased significantly in portal hypertensive rats in comparison with sham-operated control rats (P < 0.05). There was no significant difference between the two groups in endothelin-B receptor mRNA expression. Vessels of the gastric mucosa were dilated, and intravessel blood flow was increased significantly in the portal hypertensive group (P < 0.05). Diameters of mucosal vessels and blood flow were increased significantly by endothelin-A receptor antagonist (BQ-485) in the portal hypertensive rats. Endothelin-B receptor antagonist (IRL-1038) had no significant effect on mucosal microcirculation. CONCLUSION: These data suggest that increased expression of endothelin-A receptor in the portal hypertensive gastric mucosa may be related to the regulation of gastric microcirculation.

Animals↗

Florid cystic endosalpingiosis of the spleen.

A case of endosalpingiosis appearing as a huge multilocular cyst in the spleen of a 31-year-old woman is reported. The cystic lumens were smooth, and lined by fallopian tubal epithelium containing ciliated and secretory cells. The epithelial lining showed neither atypia nor foci of papillary proliferation, with only 3-5% MIB-1 labeling index. The epithelial lining was histochemically negative for mucin, but positive for MUC1 and progesterone receptor. Despite the appearance of a tumor-like mass, it was diagnosed as florid cystic endosalpingiosis as there was a normal tube-like epithelium. Regarding etiology, it was considered to derive from the secondary müllerian system of the splenic capsule.

Adult↗

Randomized controlled trial to evaluate laparoscopic surgery for colorectal cancer: Japan Clinical Oncology Group Study JCOG 0404.

A randomized controlled trial was started in Japan to evaluate whether laparoscopic surgery is the optimal treatment for colorectal cancer. Patients with T3 or deeper carcinoma in the colorectum without transverse and descending colons are pre-operatively randomized to either open or laparoscopic colorectal resection. Surgeons in 24 specialized institutions will recruit 818 patients. The primary end-point is overall survival. Secondary end-points are relapse-free survival, short-term clinical outcome, adverse events, the proportion of conversion from laparoscopic surgery to open surgery, and the proportion of completion of laparoscopic surgery.

Adult↗

Protease-activated receptor-2 regulates cell proliferation and enhances cyclooxygenase-2 mRNA expression in human pancreatic cancer cells.

BACKGROUND AND OBJECTIVES: Protease-activated receptor-2 (PAR-2) is a G protein-coupled receptor that is activated by trypsin. Recent studies have suggested that PAR-2 activity correlates with inflammatory processes and cell proliferation and that PAR-2 activation in non-neoplastic cells induces expression of cyclooxygenase-2 (COX-2). In the present study, we examined whether PAR-2 activation regulates cell proliferation and COX-2 expression by pancreatic cancer cells. METHODS: We analyzed PAR-2 expression immunohistochemically in 40 intraductal papillary-mucinous neoplasms (IPMNs) and 73 invasive ductal carcinomas (IDCs) of the pancreas. We used four pancreatic cancer cell lines (Panc1, T3M4, BxPC3, and MIApaca2) to measure cell proliferation and COX-2 mRNA expression after PAR-2 activation. RESULTS: PAR-2 protein was detected immunohistochemically in 85.0% of IPMNs and 65.8% of IDCs. Trypsin and a PAR-2 agonist peptide, SLIGKV, stimulated proliferation of each cell line in a dose-dependent manner. Exposure of cells to anti-PAR-2 neutralizing antibody prior to PAR-2 activation suppressed cell proliferation. In COX-2-positive cell lines (T3M4 and BxPC3), PAR-2 activation significantly increased COX-2 mRNA expression. CONCLUSIONS: Our results suggest that PAR-2 activation is associated with cell proliferation and COX-2 expression in pancreatic cancer cells. Blockade of the PAR-2 signaling pathway may be a novel strategy for suppressing pancreatic tumor growth.

Adenocarcinoma, Mucinous↗

Microsatellite distribution and indication for locoregional therapy in small hepatocellular carcinoma.

BACKGROUND: Intrahepatic disease recurrence is observed frequently after locoregional therapies for patients with hepatocellular carcinoma (HCC). However, the indication for locoregional therapy is still unclear. To clarify the indication for locoregional therapy for small HCC tumors, the authors measured the distance of microsatellites from the main tumor and analyzed the relation between this distance and clinicopathologic factors. METHODS: The authors retrospectively analyzed 100 patients with small HCC tumors (</= 5 cm in dimension) treated by curative hepatectomy. A microsatellite was defined as invasion into the portal vein or intrahepatic metastasis, and the distance from the main tumor to the most distant microsatellite was determined under light microscopy. The current study investigated the relation between microsatellite distance (0 mm if none present, </= 5 mm, and > 5 mm) and clinicopathologic factors, as well as overall and disease-free survival rates after hepatectomy. RESULTS: Of the 100 patients, 46 had microsatellites with a mean distance of 9.9 mm (median, 5.0 mm). Of the clinicopathologic factors investigated, tumor grade and preoperative alpha-fetoprotein level significantly correlated with the presence of a microsatellite. Tumor size and distance to the microsatellite were significantly correlated. All but 1 tumor associated with a microsatellite distance > 5 mm was a high-grade tumor > 25 mm in greatest dimension. The overall survival rate of patients with a microsatellite distance of > 5 mm was lower than that of patients with a microsatellite distance < 5 mm. CONCLUSIONS: Locoregional therapy, including limited resection and ablation therapies, was appropriate for patients with low-grade HCC tumors or with tumors < 25 mm in diameter.

Adult↗