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Featured researches published by Junichi Kamiya.


Annals of Surgery | 2006

Two hundred forty consecutive portal vein embolizations before extended hepatectomy for biliary cancer: surgical outcome and long-term follow-up.

Masato Nagino; Junichi Kamiya; Hideki Nishio; Tomoki Ebata; Toshiyuki Arai; Yuji Nimura

Objective:To assess clinical benefit of portal vein embolization (PVE) before extended, complex hepatectomy for biliary cancer. Summary Background Data:Many investigators have addressed clinical utility of PVE before simple hepatectomy for metastatic liver cancer or hepatocellular carcinoma, but few have reported PVE before hepatectomy for biliary cancer due to the limited number of surgical cases. Methods:This study involved 240 consecutive patients with biliary cancer (150 cholangiocarcinomas and 90 gallbladder cancers) who underwent PVE before an extended hepatectomy (right or left trisectionectomy or right hepatectomy). All PVEs were performed by the “ipsilateral approach” 2 to 3 weeks before surgery. Hepatic volume and function changes after PVE were analyzed, and the outcome also was reviewed. Results:There were no procedure-related complications requiring blood transfusion or interventions. Of the 240 patients, 47 (19.6%) did not undergo subsequent hepatectomy. The incidence of unresectability was higher in gallbladder cancer than in cholangiocarcinoma (32.2% versus 12.0%, P < 0.005). The remaining 193 patients (132 cholangiocarcinomas and 61 gallbladder cancers) underwent hepatectomy with resection of the caudate lobe and extrahepatic bile duct (n = 187), pancreatoduodenectomy (n = 42), and/or portal vein resection (n = 63). Seventeen (8.8%) patients died of postoperative complications: mortality was higher in gallbladder cancer than in cholangiocarcinoma (18.0% versus 4.5%, P < 0.05); and it was also higher in patients whose indocyanine green clearance (KICG) of the future liver remnant after PVE was <0.05 than those whose index was ≥0.05 (28.6% versus 5.5%, P < 0.001). The 3- and 5-year survival after hepatectomy was 41.7% and 26.8% in cholangiocarcinoma and 25.3% and 17.1% in gallbladder cancer, respectively (P = 0.011). In 136 other patients with cholangiocarcinoma who underwent a less than 50% resection of the liver without PVE, a mortality of 3.7% and a 5-year survival of 27.6% were observed, which was similar to the 132 patients with cholangiocarcinoma who underwent extended hepatectomy after PVE. Conclusions:PVE has the potential benefit for patients with advanced biliary cancer who are to undergo extended, complex hepatectomy. Along with the use of PVE, further improvements in surgical techniques and refinements in perioperative management are necessary to make difficult hepatobiliary resections safer.


Annals of Surgery | 2003

Hepatectomy with portal vein resection for hilar cholangiocarcinoma: audit of 52 consecutive cases.

Tomoki Ebata; Masato Nagino; Junichi Kamiya; Katsuhiko Uesaka; Tetsuro Nagasaka; Yuji Nimura

Objective: To better determine the role of portal vein resection and its effect on survival, as well as to appreciate the impact of portal vein invasion on prognosis in hilar cholangiocarcinoma. Summary Background Data: Hepatectomy with portal vein resection is sometimes performed for locally advanced hilar cholangiocarcinoma. However, the significance of microscopic invasion of the portal vein has not been determined. Methods: Medical records of 160 patients with hilar cholangiocarcinoma who underwent macroscopically curative hepatectomy with (n = 52) or without portal vein resection (n = 108) were reviewed. Invasion of the portal vein was assessed histologically on the surgical specimen, and results were correlated with clinicopathologic features and survival. Results: Surgical mortality, including all hospital deaths, was similar in patients who did and did not undergo portal vein resection (9.6% vs. 9.3%), but the primary tumor was more advanced in patients who underwent portal vein resection. Histologically, no invasion was found in 16 (30.8%) of resected portal veins. However, dense fibrosis adjacent to the portal vein was common, and the mean distance between the leading edge of cancer cells and the adventitia of the portal vein was 437 ± 431 &mgr;m. The prognosis was worse in patients with than without portal vein resection (5-year survival, 9.9% vs. 36.8%; P < 0.0001). The presence or absence of microscopic invasion of the resected portal vein did not influence survival (16.6 months in patients with microscopic invasion vs. 19.4 months in those without; P = 0.1506). Multivariate analysis identified histologic differentiation, lymph node metastasis, and macroscopic portal vein invasion as independent prognostic factors. Conclusions: Microscopic invasion of the portal vein may be misdiagnosed clinically in patients with hilar cholangiocarcinoma. However, the distance between tumor and adventitia is so narrow that curative resection without portal vein resection is unlikely to be possible. Gross portal vein invasion has a negative impact on survival, and hepatectomy with portal vein resection can offer long-term survival in some patients with advanced hilar cholangiocarcinoma.


Annals of Surgery | 2001

Lymph Node Metastasis from Hilar Cholangiocarcinoma: Audit of 110 Patients Who Underwent Regional and Paraaortic Node Dissection

Yuichi Kitagawa; Masato Nagino; Junichi Kamiya; Katsuhiko Uesaka; Tsuyoshi Sano; Hideo Yamamoto; Naokazu Hayakawa; Yuji Nimura

ObjectiveTo assess the status of the regional and paraaortic lymph nodes in hilar cholangiocarcinoma and to clarify the efficacy of systematic extended lymphadenectomy. Summary Background DataThere have been no studies in which regional and paraaortic lymphadenectomies for hilar cholangiocarcinoma have been routinely performed. Therefore, the metastasis rates to the regional and paraaortic nodes, the mode of lymphatic spread, and the effect of extended lymph node dissection on survival remain unknown. MethodsThis study involved 110 patients who underwent surgical resection for hilar cholangiocarcinoma with lymph node dissection including both the regional and paraaortic nodes. A total of 2,652 nodes retrieved from the surgical specimens were examined microscopically. ResultsOf the 110 patients, 52 (47.3%) had no involved nodes, 39 (35.5%) had regional lymph node metastases, and 19 (17.3%) had regional and paraaortic node metastases. The incidence of positive nodes was significantly higher in the patients with pT3 disease than in those with pT2 disease. The pericholedochal nodes were most commonly involved (42.7%), followed by the periportal nodes (30.9%), the common hepatic nodes (27.3%), and the posterior pancreaticoduodenal nodes (14.5%). The celiac and superior mesenteric nodes were rarely involved. The 3-year and 5-year survival rates were 55.4% and 30.5% for the 52 patients without involved nodes, 31.8% and 14.7% for the 39 patients with regional node metastases, and 12.3% and 12.3% for the 19 patients with paraaortic node metastases, respectively. Of the 19 patients with positive paraaortic nodes, 7 had no macroscopic evidence of paraaortic disease on intraoperative inspection. The survival in this group was significantly better than in the remaining 12 patients. ConclusionThe paraaortic nodes and the regional nodes are frequently involved in advanced hilar cholangiocarcinoma. Whether extended lymph node dissection provides a survival benefit requires further study. However, the fact that long-term survival is possible despite pN2 or pM1 disease encourages the authors to perform an aggressive surgical procedure with extended lymph node dissection in selected patients with hilar cholangiocarcinoma.


Annals of Surgery | 2000

Management of Hilar Cholangiocarcinoma: Comparison of an American and a Japanese Experience

Jane I. Tsao; Yuji Nimura; Junichi Kamiya; Naokazu Hayakawa; Satoshi Kondo; Masato Nagino; Masahiko Miyachi; Michio Kanai; Katsuhiko Uesaka; Koji Oda; Ricardo L. Rossi; John W. Braasch; John M. Dugan

ObjectiveTo compare the experience and outcome in the management of hilar cholangiocarcinoma at one American and one Japanese medical center. Summary Background DataControversies surround the issues of extent of resection for hilar cholangiocarcinoma and whether the histopathology of such cancers are similar between patients treated in America and in Japan. MethodsRecords were reviewed of 100 patients treated between 1980 and 1995 at the Lahey Clinic in the United States, and of 155 patients treated between 1977 and 1995 at Nagoya University Hospital in Japan. Selected pathologic slides of resected cancers were exchanged between the two institutions and reviewed for diagnostic concordance. ResultsIn the Lahey cohort, there were 25 resections, 53 cases of surgical exploration with biliary bypass or intubation, and 22 cases of percutaneous transhepatic biliary drainage or endoscopic biliary drainage without surgery. In the Nagoya cohort, the respective figures were 122, 10, and 23. The overall 5-year survival rate of all patients treated (surgical and nonsurgical) during the study periods was 7% in the Lahey cohort and 16% in the Nagoya cohort. The overall 10-year survival rates were 0% and 12%, respectively. In patients who underwent resection with negative margins, the 5- and 10-year survival rates were 43% and 0% for the Lahey cohort and 25% and 18% for the Nagoya cohort. The surgical death rate for patients undergoing resection was 4% for Lahey patients and 8% for Nagoya patients. Of the patients who underwent resection, en bloc caudate lobectomy was performed in 8% of the Lahey patients and 89% of the Nagoya patients. Histopathologic examination of resected cancers showed that the Nagoya patients had a higher stage of disease than the Lahey patients. ConclusionsIn both Lahey and Nagoya patients, survival was most favorable when resection of hilar cholangiocarcinoma was accomplished with margin-negative resections. Combined bile duct and liver resection with caudate lobectomy contributed to a higher margin-negative resection rate in the Nagoya cohort.


Annals of Surgery | 1998

The pattern of infiltration at the proximal border of hilar bile duct carcinoma. A histologic analysis of 62 resected cases

Eiji Sakamoto; Yuji Nimura; Naokazu Hayakawa; Junichi Kamiya; Satoshi Kondo; Masato Nagino; Michio Kanai; Masahiko Miyachi; Katsuhiko Uesaka

OBJECTIVE To clarify the importance of different patterns of infiltration at the proximal border of hilar bile duct carcinomas. SUMMARY BACKGROUND DATA There are few detailed pathologic studies on the proximal resection margins in patients with hilar bile duct carcinoma. METHODS Serial sections of 62 specimens of resected hilar bile duct carcinoma were examined histologically to determine the involved layers and routes of invasion at the proximal border. The degree of cancer extension was determined, and the relation between the length of the tumor-free resection margin and postoperative anastomotic recurrences was analyzed. RESULTS Mucosal extension was predominant in papillary and nodular tumors, but submucosal extension was predominant in diffusely infiltrating and nodular-infiltrating tumors. Submucosal extension usually consisted of direct or lymphatic invasion. The mean length of submucosal extension was 6.0 mm. Superficial spread of cancer, defined as mucosal extension of more than 20 mm from the main lesion, was seen in 8 specimens. No patient had an anastomotic recurrence when the tumor-free resection margin was greater than 5 mm. CONCLUSIONS The pattern of infiltration at the proximal border of resected hilar bile duct carcinomas is closely related to the gross tumor type. The length of submucosal extension is usually less than 10 mm. Superficial spread of cancer is seen in more than 10% of cases. A tumor-free proximal resection margin of 5 mm appears to be adequate in hilar bile duct carcinoma.


Surgery | 1995

Right or left trisegment portal vein embolization before hepatic trisegmentectomy for hilar bile duct carcinoma.

Masato Nagino; Yuji Nimura; Junichi Kamiya; Satoshi Kondo; Katsuhiko Uesaka; Yukoh Kin; Yasushi Kutsuna; Naokazu Hayakawa; Hideo Yamamoto

BACKGROUND Percutaneous transhepatic embolization of the right portal vein plus the left medial portal branch (R3-PE) and the left portal vein plus the right anterior portal branch (L3-PE) is not well described. METHODS Four patients with far advanced carcinoma of the hepatic hilus underwent R3-PE (n = 1) or L3-PE (n = 3) as preoperative management for right hepatic trisegmentectomy or left hepatic trisegmentectomy. The portal vein embolization was performed with the ipsilateral approach through the right anterior portal branch. RESULTS In all patients the embolizations were successful without complications. Volumetric study with computed tomography showed sufficient hypertrophy of the nonembolized hepatic segments. Three of the four patients eventually underwent trisegmentectomy. The postoperative courses in two of the patients were uneventful. The remaining patient suffered from posthepatectomy liver failure but recovered. CONCLUSIONS R3-PE or L3-PE is advisable as preoperative management for trisegmentectomy and appears effective for increasing the safety of the operation. This embolization is achievable only through the ipsilateral approach.


Annals of Surgery | 1992

Clinicopathologic studies on perineural invasion of bile duct carcinoma

Md. Mukhlesur Rahman Bhuiya; Yuji Nimura; Junichi Kamiya; Satoshi Kondo; Shinji Fukata; Naokazu Hayakawa; Shigehiko Shionoya

To elucidate the clinical significance of perineural invasion on bile duct cancer, a clinicopathologic study was performed on 70 resected patients with bile duct carcinoma. The overall incidence of perineural invasion in the resected specimen was 81.4%. There seemed to be no correlation between perineural invasion and site, size of the tumor, and lymph node metastasis. A significant correlation was observed, however, between macroscopic type, microscopic type, depth of invasion, and perineural invasion. Perineural invasion index (PNI) was defined as the ratio between the number of nerve fibers invaded by cancer and the total number of nerve fibers with and without cancer invasion. Perineural invasion index was significantly higher at the center compared with the proximal and distal part of the tumor (p less than 0.001). The 5-year survival rate for patients with perineural invasion was significantly lower (p less than 0.05) than that for those without perineural invasion (67% versus 32%).


Annals of Surgery | 2004

Surgical anatomy of the bile ducts at the hepatic hilum as applied to living donor liver transplantation.

Masayuki Ohkubo; Masato Nagino; Junichi Kamiya; Norihiro Yuasa; Koji Oda; Toshiyuki Arai; Hideki Nishio; Yuji Nimura

Objective:To evaluate anatomic variations of the biliary tree as applied to living donor liver transplantation. Summary Background Data:Anatomic variability is the rule rather than the exception in liver surgery. However, few studies have focused on the anatomic variations of the biliary tree in living donor liver transplantation in relation to biliary reconstruction. Methods:From November 1992 to June 2002, 165 patients underwent major hepatectomy with extrahepatic bile duct resection; right-sided hepatectomy in 110 patients and left-sided hepatectomy in 55. Confluence patterns of the intrahepatic bile ducts at the hepatic hilum in the surgical specimens were studied. Results:Confluence patterns of the right intrahepatic bile ducts were classified into 7 types. The right hepatic duct was absent in 4 of the 7 types and in 29 (26%) of the 110 livers. Confluence patterns of the left intrahepatic bile ducts were classified into 4 types. The left hepatic duct was absent in 1 of the 4 types and in 1 (2%) of the 55 livers. Conclusions:In harvesting the right liver from a donor without a right hepatic duct, 2 or more bile duct stumps will be present in the plane of transection in the graft in 3 patterns based on their relation to the portal vein. Accurate knowledge of the variations in the hepatic confluence is essential for successful living donor liver transplantation.


British Journal of Surgery | 2002

Extensive surgery for carcinoma of the gallbladder

Satoshi Kondo; Yuji Nimura; Naokazu Hayakawa; Junichi Kamiya; Masato Nagino; K. Uesaka

The purpose of this study was to clarify the efficacy of, and define the indications for, extensive surgery for gallbladder carcinoma.


World Journal of Surgery | 2001

Complications of Hepatectomy for Hilar Cholangiocarcinoma

Masato Nagino; Junichi Kamiya; Katsuhiko Uesaka; Tsuyoshi Sano; Hideo Yamamoto; Naokazu Hayakawa; Michio Kanai; Yuji Nimura

Abstract. We retrospectively reviewed postoperative complications in 105 patients with hilar cholangiocarcinoma who underwent hepatectomy at Nagoya University Hospital from January 1990 through March 1999. Of the 105 subjects, 97 (92.4%) underwent resection of two or more Healeys segments of the liver. Combined portal vein resection was performed in 33 (31.4%) patients and pancreatoduodenectomy in 10 (9.5%). Twenty (19.0%) patients had no postoperative complications, another 39 (37.1%) patients had minor complication(s) only, and the remaining 46 (43.8%) developed major complication(s). The morbidity rate reached as high as 81.0%. Major complications required relaparotomy in 11 (10.5%) patients. Of the 46 patients with major complication(s) 36 recovered; the remaining 10 patients died of liver failure with other organ failure(s) or of intraabdominal bleeding 12, 14, 18, 21, 57, 75, 75, 87, 93, or 134 days after surgery. Thus the 30-day mortality was 3.8% and the overall mortality 9.5%. Pleural effusion was the most frequent complication found in 66 (62.9%) patients, followed by wound sepsis in 39 (37.1%), and then liver failure in 29 (27.6%). Liver failure developed in 16.7% of 48 patients with less than 50% liver resection and in 36.8% of 57 patients with 50% or more resection (P < 0.05). Other organ failures, including renal, respiratory, gastrointestinal, and hematologic failures, developed as a sign of multiple organ failure following liver failure in most patients or preceding liver failure in a few patients. None of the six patients with four or more organ failures survived. Hepatectomy for hilar cholangiocarcinoma is risky owing to impaired hepatic functional reserve in jaundiced patients and the technical difficulty associated with hepatobiliary resection. Our goal is to reduce mortality to less than 5% while keeping a high resectability rate (above 80%).

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