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Dive into the research topics where Kiyoshi Kajiyama is active.

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Featured researches published by Kiyoshi Kajiyama.


Human Pathology | 1995

Combined hepatocellular and cholangiocarcinoma: Proposed criteria according to cytokeratin expression and analysis of clinicopathologic features

Takashi Maeda; Eisuke Adachi; Kiyoshi Kajiyama; Keizo Sugimachi; Masazumi Tsuneyoshi

We herein evaluated 36 cases of combined hepatocellular and cholangiocarcinoma (cHCC-CC) (including 29 surgically resected and seven autopsy cases) by the immunohistochemical methods of anticytokeratin antibodies 7 and 19, and then analyzed the clinicopathologic features by comparing cHCC-CC with ordinary hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). The results indicated that even if mucin production could not be confirmed, nine cases with HCC areas that showed a histological resemblance to CC also showed immunohistological biliary differentiation. Therefore, we advocate that these HCC with biliary differentiation based on an immunohistochemical analysis should thus be included in the criteria of cHCC-CC in broad terms. Regardless of the extent of mucin production, the cHCC-CCs as indicated by an immunohistochemical analysis are considered to have a similar background to that of ordinary HCCs regarding such factors as the average age, male:female ratio, hepatitis B surface antigen (HBsAg) and hepatitis C virus antibody (HCVAb) positivity, alpha-fetoprotein level, and the presence of cirrhosis. However, cHCC-CCs tend to metastasize to many organs and the lymph nodes, and, as a result, have a poor prognosis.


Annals of Surgery | 1998

Prognostic factors after repeat hepatectomy for recurrent hepatocellular carcinoma.

Mitsuo Shimada; Kenji Takenaka; Kenichi Taguchi; Yuh Fujiwara; Tomonobu Gion; Kiyoshi Kajiyama; Takashi Maeda; Ken Shirabe; Katsuhiko Yanaga; Keizo Sugimachi

OBJECTIVE The aims of this study were to identify prognostic factors in patients who developed recurrent hepatocellular carcinoma (HCC) after repeat hepatectomy and to elucidate the role of multicentric occurrence in the second tumor after a first hepatectomy. SUMMARY BACKGROUND DATA A repeat hepatectomy for recurrent HCC has been established as the most effective treatment modality, whenever it is possible. However, the prognostic factors for recurrent HCC after repeat hepatectomy have yet to be clarified. METHODS Forty-one patients who underwent a curative repeat hepatectomy were retrospectively studied. Patient survival and disease-free survival after recurrence were univariately and multivariately analyzed using 38 clinicopathologic variables. The histologic grade of HCC at repeat hepatectomy was also compared with that at first hepatectomy. RESULTS Patient survival after repeat hepatectomy did not differ substantially from that in 312 patients undergoing primary hepatectomy. However, the disease-free survival after repeat hepatectomy was significantly lower than that in patients with only a primary hepatectomy (p < 0.05). Multivariate analysis revealed only portal vein invasion in the first hepatectomy to be an independent and significantly poor prognostic factor. Regarding multicentric occurrence at repeat hepatectomy, only 6 of 40 patients (15%) whose specimens could be evaluated histologically were determined to be Edmondson and Steiners Grade 1. CONCLUSIONS The only prognostic factor identified in patients with recurrent HCC after repeat hepatectomy was portal vein invasion in the first hepatectomy. Most second tumors after the first hepatectomy are considered to be caused by metastatic recurrence, not by multicentric occurrence.


Modern Pathology | 2001

Altered expression of beta-catenin without genetic mutation in intrahepatic cholangiocarcinoma

Keishi Sugimachi; Kenichi Taguchi; Shinichi Aishima; Shinji Tanaka; Mitsuo Shimada; Kiyoshi Kajiyama; Keizo Sugimachi; Masazumi Tsuneyoshi

β-catenin which has a role in E-cadherin mediated cell-to-cell adhesion, and is also involved in Wnt signaling pathways as a downstream signaling molecule accumulating in the cytoplasm and nucleus constitutively activates Tcf/LEF-associated transcription of oncogenic genes. We examined the expression pattern and the genetic alteration of β-catenin to determine the role of β-catenin in cancer formation and/or progression in intrahepatic cholangiocarcinoma (ICC). β-catenin expression was immunohistochemically examined in 71 surgically resected ICC samples, and correlation between the expression pattern and clinicopathologic factors was investigated. Mutation analysis of β-catenin exon 3, which included the responsible element for Wnt signaling was done in 55 samples, using PCR-SSCP and direct sequence methods. Immunohistochemical analysis revealed the reduced membranous expression of β-catenin in 58 (82%) ICCs and aberrant nuclear expression in 11 (15%) ICCs. The membranous expression was preserved in 62% of the papillary adenocarcinomas, and was frequently reduced in tumors with a poorer histological differentiation (84%), with a significant difference (P =.01). Genetic analysis showed that none of the 55 ICCs examined carried mutations in β-catenin exon 3. The present study indicates that reduced membranous expression of β-catenin is associated with non-papillary ICCs which have a more malignant behavior, and that nuclear translocation of β-catenin results in oncogenic events. Mutations in β-catenin exon 3 do not appear to be responsible for nuclear translocation of β-catenin in ICCs.


Surgical Endoscopy and Other Interventional Techniques | 1995

Laparoscopic hepatic resection for hepatocellular carcinoma

Makoto Hashizume; Kenji Takenaka; Katsuhiko Yanaga; Mitsuhiko Ohta; Kiyoshi Kajiyama; Ken Shirabe; Hidetoshi Itasaka; Takashi Nishizaki; Keizo Sugimachi

Despite recent progress in diagnostics for hepatocellular carcinoma, the rate of resectability remains low, mainly because of the advancement of the underlying liver disease. We report a case of a 54-year-old man with a hepatocellular carcinoma and poor liver function that was treated successfully with a laparoscopic hepatic resection. Laparoscopic hepatic resection is considered to be feasible with the aid of an ultrasonic dissector and a microwave coagulator; however, close attention should be paid to the development of air embolism and hepatic vein injury.


Journal of Hepatology | 2001

The role of overexpression and gene amplification of cyclin D1 in intrahepatic cholangiocarcinoma

Keishi Sugimachi; Shinichi Aishima; Kenichi Taguchi; Shinji Tanaka; Mitsuo Shimada; Kiyoshi Kajiyama; Keizo Sugimachi; Masazumi Tsuneyoshi

BACKGROUND/AIMS Intrahepatic cholangiocarcinoma (ICC) is a primary liver malignant tumor with an extremely poor prognosis, but less attention has been directed to factors related to molecular carcinogenesis, including cell cycle proteins. We examined the expression and gene amplification of cyclin D1, the cell cycle regulating protein. Our objective was to evaluate correlations with clinicopathological factors in ICC. METHODS Cyclin D1 overexpression and cellular proliferative activity (Ki-67 labeling index) were investigated immunohistochemically, and 20 cases were further investigated for cyclin D1 gene amplification, using differential PCR. We examined the correlation between the expression and gene amplification of cyclin D1 and clinicopathological factors, including overall survival in patients with ICC. RESULTS Immunohistochemical analysis revealed an overexpression of cyclin D1 protein in 28 of 66 subjects with ICCs (42%). The cyclin D1 overexpression was associated with poor histological differentiation (P = 0.04), high cellular proliferative activity (P < 0.01), and a poor prognosis (P = 0.02) by univariate analysis, although it is not an independent prognostic factor by multivariate analysis. Cyclin D1 gene amplification was confirmed in five of the 20 patients. Of those five cases of ICC, all had poor histological differentiation, and four of the five ICCs (80%) showed evidence of cyclin D1 immunoreactivity. CONCLUSIONS Overexpression and gene amplification of cyclin D1 are frequent and contribute to dedifferentiation and cellular proliferative activity of ICCs, and overexpression also indicates a poor prognosis for patients with ICC.


Journal of Gastroenterology and Hepatology | 1995

CD34 expression in endothelial cells of small hepatocellular carcinoma: Its correlation with tumour progression and angiographic findings

Takashi Maeda; Eisuke Adachi; Kiyoshi Kajiyama; Kenji Takenaka; Hiroshi Honda; Keizo Sugimachi; Masazumi Tsuneyoshi

The angiogenic process plays an important role in tumour growth and metastasis during hepatocarcinogenesis, but it is still uncertain when the process begins during tumour formation. Forty‐two small hepatocellular carcinomas (HCC) that measured either less than or equal to 2 cm in diameter were studied by comparing the histologic findings with the angiographic findings, and with immunohistochemical expression of endothelial marker QB‐end/10 (QB), a new monoclonal antibody raised against CD34, in the sinusoidal wall. Twenty (91%) of 22 moderately or poorly differentiated HCC revealed a positive reaction for QB, while only eight (40%) of 20 well differentiated HCC demonstrated a positive reaction (P < 0.01). In the tumours showing a ‘nodule in nodule’ appearance, the less differentiated areas were more reactive for QB. Twenty‐three (82%) of 28 QB positive tumours were hypervascular, while only three of 14 (21%) QB negative tumours were hypervascular (P < 0.01) by angiography. All six of the poorly differentiated and 13 (81%) of the 16 moderately differentiated tumours were hypervascular, while only seven (35%) of 20 well differentiated HCC were hypervascular (P < 0.01). These results indicate that as the tumour becomes less differentiated, the QB positive areas become wider and angiography demonstrates hypervascularity. We therefore speculate that the HCC sinusoids acquire the characteristics of capillary and precapillary blood vessels during de‐differentiation from well to moderate, and thus the tumour begins to reveal hypervascularity on angiography. The above process may be correlated with the stepwise progression of HCC.


Surgery | 1999

Expression of matrix metalloproteinase-9 in surgically resected intrahepatic cholangiocarcinoma

Ken Shirabe; Mitsuo Shimada; Kiyoshi Kajiyama; Hirofumi Hasegawa; Tomonobu Gion; Yasuharu Ikeda; Kenji Takenaka; Keizo Sugimachi

BACKGROUND Matrix metalloproteinase-9 (MMP-9) has recently been reported to be related to cancer cell invasion. This study was performed to clarify the expression of MMP-9 in surgically resected intrahepatic cholangiocarcinoma (IHCC). METHODS In 37 patients with IHCC who underwent a surgical resection, the expression of MMP-9 and the clinicopathologic characteristics of MMP-9-positive IHCC were investigated. The expression of MMP-9 was immunohistochemically detected in 16 (43%) of 37 IHCC. The patients were divided into MMP-9 (-) IHCC (n = 21), MMP-9 (+) IHCC (n = 12), and MMP-9 (++) IHCC (n = 4). RESULTS The survival rate after surgical resection in patients with MMP-9 (-), (+), and (++) IHCC, was 66%, 39%, and 0% at one year, 50%, 32% and 0% at 3 years, respectively (P = .001). The incidence rate of lymph node metastasis was 6 (28%) of 21 in MMP-9 (-) patients, 7 (58%) of 12 in MMP-9 (+) patients and 4 (100%) of 4 in MMP-9 (++) patients. The incidence rate of lymph node metastasis increased in proportion to an increase in the expression of MMP-9 in IHCC (P = .02). Recurrence in the lymph node was more common in patients with MMP-9 (+) and (++) cancers than in those with MMP-9 (-) cancers. CONCLUSIONS The expression of MMP-9 in IHCC was a prognostic factor related to lymph node metastasis.


Surgery | 1996

Surgical treatment strategy for patients with stage IV hepatocellular carcinoma

Mitsuo Shimada; Kenji Takenaka; Naoyuki Kawahara; Kiyoshi Kajiyama; Kazuharu Yamamoto; Ken Shirabe; Takashi Nishizaki; Katsuhiko Yamaga; Keizo Sugimachi

BACKGROUND This study was conducted to identify the prognostic indicators for patients with stage IV hepatocellular carcinoma (HCC), as well as to clarify the strategy of surgical treatment for those patients. METHODS Forty-six patients with stage IV HCC were included in this study. Prognostic factors were univariately and multivariately analyzed. Furthermore, the significance of intraoperative treatment for residual tumors was investigated in patients with an absolute noncurative operation. RESULTS The poor prognostic factors were as follows: host factors, Childs classification of B and C and immunosuppressive acidic protein level of greater than 400 micrograms/ml; tumor factors, tumor diameter of greater than 5 cm, poorly differentiated histologic features, positive portal vein invasion, and intrahepatic metastases involving more than three segments; others, an absolute noncurative operation and no preoperative treatment. Tumor diameter of more than 5 cm was then suggested to be an independent prognostic indicator. Survival of patients with stage IV-A HCC who underwent a curative operation was similar to that of those with stages III HCC: Furthermore, the survival of patients with Stage IV-A who had an absolute noncurative operation but underwent either intraoperative microwave coagulation or ethanol injection to the residual HCCs was not statistically different from that of those with a curative operation. CONCLUSIONS Therefore for stage IV-A HCC surgical treatment is considered to be both useful and the first choice of treatment when all the tumors in the liver can be removed or when the residual tumors can be treated during operation by either microwave coagulation or ethanol injection as a result of an incomplete removal of the tumors.


Journal of Surgical Oncology | 1996

Immunohistochemical expression of Sialyl Tn, Sialyl Lewisa, Sialyl Lewisa−b−, and Sialyl Lewisx in primary tumor and metastatic lymph nodes in human gastric cancer

Yoichi Ikeda; Masaki Mori; Kiyoshi Kajiyama; Yukiaki Haraguchi; Osamu Sasaki; Keizo Sugimachi

Sialyl Lewis Tn(STN), Sialyl Lewisa(CA19‐9), Sialyl Lewisa−b−(DU‐PAN‐2), and Sialyl Lewisx(SLX) antigens were immunohistochemically examined in the primary tumor and metastatic lymph nodes in 35 patients with advanced gastric cancer. STN, CA 19‐9, DU‐PAN‐2, and SLX were expressed in 91%, 60%, 31%, and 60% in the primary lesion, and 77%, 54%, 22%, and 51% in the metastatic lesion, respectively. In only four cases, (11%) were all four antigens expressed in both the primary and metastatic lesions. Three antigens were expressed in 49% of primary lesions and in 20% of metastatic lesions. Compared with expression in primary lesions, increased, unchanged and decreased expressions in metastatic lesions were noted in 23%, 37%, and 40% for STN, 20%, 40%, and 40% for CA19‐9, 17%, 57%, and 26% for DU‐PAN‐2, and 26%, 31%, and 43% for SLX, respectively. These results indicate that the tumor in the primary and metastatic lesions has a heterogeneous expression of sialyl‐related antigens. However, metastases cannot be predicted based upon the expression of these antigens.


World Journal of Gastroenterology | 2011

Prospective randomized controlled trial investigating the type of sutures used during hepatectomy

Norifumi Harimoto; Ken Shirabe; Tomoyuki Abe; Takafumi Yukaya; Eiji Tsujita; Tomonobu Gion; Kiyoshi Kajiyama; Takashi Nagaie

AIM To determine whether absorbable sutures or non-absorbable sutures are better in preventing surgical site infection (SSI), in this paper we discuss the results of a randomized clinical trial which examined the type of sutures used during hepatectomy. METHODS All hepatic resections performed from January 2007 to November 2008 at the Department of Surgery at Iizuka Hospital in Japan were included in this study. There were 125 patients randomly assigned to an absorbable sutures (Vicryl) group or non-absorbable sutures (Silk) group. RESULTS SSI was observed in 13.6% (17/125) patients participating in this study, 11.3% in the Vicryl group and 15.8% in the Silk group. Incisional SSI including superficial and deep SSI, was observed in 8% of the Vicryl group and 9.5% of the Silk group. Organ/space SSI was observed in 3.2% of the Vicryl group and 6.0% of the Silk group. There were no significant differences, but among the patients with SSI, the period for recovery was significantly shorter for the Vicryl group compared to the Silk group. CONCLUSION The incidence of SSI in patients receiving absorbable sutures and silk sutures is not significantly different in this randomized controlled study; however, the period for recovery in patients with SSI was significantly shorter for absorbable sutures.

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Yoshihiko Maehara

Tokyo Medical and Dental University

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