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Featured researches published by Naokazu Hayakawa.


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%).


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%).


Surgical Endoscopy and Other Interventional Techniques | 1988

Value of percutaneous transhepatic cholangioscopy (PTCS)

Yuji Nimura; Shigehiko Shionoya; Naokazu Hayakawa; Junichi Kamiya; Satoshi Kondo; Akihiro Yasui

SummarySince July 1975, percutaneous transhepatic biliary drainage (PTBD) has been performed in 533 cases, and since April 1977 we have developed percutaneous transhepatic cholangioscopy (PTCS) as a diagnostic and therapeutic endoscopical tool in 198 cases of malignant disease and 195 benign cases. After dilating the sinus tract of PTBD using a 15-Fr catheter about 2 weeks after PTBD, PTCS was carried out through the sinus tract. PTCS has diagnostic advantages: the lesion can be accurately diagnosed histologically and the extent of cancer in the biliary tract can be assessed by taking biopsy specimens before the operation. PTCS has been applied for cholangioscopic lithotripsy in 145 cases of gallstone disease. In 44 cases, the Nd-YAG laser and/or electrohydraulic shock wave has been used to break up the stones. The PTCS morbidity was 6% and mortality was 0.3%.


International Journal of Gastrointestinal Cancer | 1997

Distal Pancreatectomy with En Bloc Resection of the Celiac Artery for Carcinoma of the Body and Tail of the Pancreas

Toshihiko Mayumi; Yuji Nimura; Junichi Kamiya; Satoshi Kondo; Masato Nagino; Michio Kanai; Masahiko Miyachi; Katsura Hamaguchi; Naokazu Hayakawa

SummaryConclusionCombined resection of the celiac artery with a distal pancreatectomy (DP) increases the resectability and improves the overal prognosis of patients with locally advanced ductal cancer of the body and tail of the pancreas.BackgroundCarcinoma of the body and tail of the pancreas is often unresectable because of invasion to adjacent organs. We evaluated a DP including anen bloc resection of the celiac artery (“extended”), for pancreatic cancer that had invaded the common hepatic and/or celiac arteries.MethodsSix cases of an “extended” DP were compared with 19 cases of a “standard” DP for pancreatic ductal carcinoma in terms of clinical and pathologic findings, perioperative course, and long-term outcome. We also compared the survival rate of these two groups with a third group consisting of 22 patients with unresectable pancreatic ductal carcinoma.ResultsThe mean operative time, postoperative serum aspartate aminotransferase concentration, and length of hospital stay did not significantly differ between the “extended” and “standard” DP groups. The cumulative 1- and 3-yr accumulated survival rates for the “extended,” “standard,” and unresectable groups were 40.0, 33.3, and 5.4, and 20.0, 16.6, and 0%, respectively. Statistically significant differences (p<0.01) existed between the “extended” and unresected groups.


Journal of Hepato-biliary-pancreatic Surgery | 1995

Hilar cholangiocarcinoma—surgical anatomy and curative resection

Yuji Nimura; Naokazu Hayakawa; Junichi Kamiya; Satoshi Kondo; Masato Nagino; Michio Kanai

We have studied the surgical anatomy of the intrahepatic bile duct, hepatic hilus, and caudate lobe based on intraoperative findings and selective cholangiography of surgical patients and resected specimens, and have established the cholangiographic anatomy of the intrahepatic subsegmental bile duct. Thorough knowledge of the three-dimensional anatomy of the subsegmental bile duct, hepatic hilus, and caudate lobe is indispensable for curative surgery of hilar cholangiocarcinoma. We designed and actually performed 15 kinds of hepatic segmentectomies with caudate lobectomy and extrahepatic bile buct resection in 100 consecutive patients, with curative resection being possible in 82 patients. Postoperative survival after curative resection of hilar cholangiocarcinoma was better than expected, and the 5-year survival rates for all 82 patients with curative resection and for 55 patients with curative surgery without portal vein resection were 31% and 43%, respectively. Hepatic segmentectomy with caudate lobectomy and extrahepatic bile duct resection should be designed not only in accordance with the preoperative diagnosis of tumor extension into the intrahepatic bile ducts but also so that curative surgery for advanced hilar cholangiocarcinoma can be performed.

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