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Dive into the research topics where Kazuhiro Ogasawara is active.

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Featured researches published by Kazuhiro Ogasawara.


Cancer | 1985

An AFP-producing gastric carcinoma with features of hepatic differentiation: a case report

Hiroshi Ishikura; Yuichiro Fukasawa; Kazuhiro Ogasawara; Takashi Natori; Yutaka Tsukada; Miki Aizawa

A patient with primary gastric adenocarcinoma with extremely high serum alpha‐fetoprotein (AFP) levels (12,000 ng/ml) is described. Histologically, foci strongly resembling hepatocellular carcinoma with hyaline globules were noted. Within tumor cells, AFP was identified with both light and electron microscopy, showing the production of AFP by tumor cells themselves. Furthermore, 88% of serum AFP combined with Concanavalin A (ConA), revealing that it was hepatic‐type AFP and not germcell‐type. Localization of alpha‐I‐antitrypsin within tumor cells was also noted. Ultrastructural study showed that there were two types of structures corresponding to periodic acid‐Schiff (PAS)‐positive globules, one of which, the proteinaceous material in intracytoplasmic lumina, was found to contain AFP. Among gastric adenocarcinomas with a high serum AFP level (several thousand or more ng/ml of AFP), foci resembling hepatocellular carcinomas have been reported by several investigators. Those gastric carcinomas, together with the current case, may constitute a clinicopathologic entity, hepatoid adenocarcinoma of the stomach.


Surgery | 1997

Efficacy and safety of preoperative percutaneous transhepatic portal embolization with absolute ethanol: A clinical study

Tsuyoshi Shimamura; Yasuaki Nakajima; Yoshie Une; Tsutomu Namieno; Kazuhiro Ogasawara; Kenichiro Yamashita; Tsutomu Haneda; Kazuaki Nakanishi; Jun Kimura; Michiaki Matsushita; Naoki Sato; Junichi Uchino

BACKGROUND Preoperative portal embolization has been performed by using various thrombogenic substances to increase the safety and resectability of liver surgery. We evaluated the clinical safety and efficacy of using absolute ethanol in preoperative portal embolization. METHODS Our study included 19 patients who had undergone right hepatic lobectomy. According to our criteria for right lobectomy of the liver, seven patients were not appropriate for the operation because of a high risk in each of postoperative liver failure. Those patients received preoperative right portal embolization with 11 to 32 ml absolute ethanol. The remaining 12 patients satisfied our criteria and received no preoperative embolization. RESULTS Although alanine aminotransferase concentrations increased dramatically after the embolization, all serologic changes reverted within 3 weeks. The mean volume of the nonembolized lobe increased from 320 cm3 to 619 cm3 and 667 cm3 2 and 4 weeks, respectively, after embolization. The mean regeneration rate of this lobe was 21.3 cm3 per day for the first 2 weeks and 11.4 cm3 per day for the first 4 weeks after embolization. All patients underwent right lobectomy of the liver and survived; none of the patients had severe complications associated with embolization or surgery. The postoperative survival periods were not statistically significant between the patients with and without preoperative portal embolization. CONCLUSIONS According to our criteria for liver surgery, the seven patients should not have undergone major surgery, but each underwent right lobectomy of the liver and all survived, showing that portal embolization with absolute ethanol brings about compensatory hepatic hypertrophy for major surgery and that its extreme effect on liver regeneration could widen the range of patients appropriate for liver surgery.


Surgery Today | 1995

The significance of measuring liver volume using computed tomographic images before and after hepatectomy

Kazuhiro Ogasawara; Yoshie Une; Yasuaki Nakajima; Junichi Uchino

The authors have developed a system to measure the volume of the liver parenchyma and tumors using computed tomographic images printed on film. The present study was carried out to clarify the usefulness of this method to assess both liver volume and the relationship between the volume increase and the functional recovery. We investigated 55 patients who underwent a hepatic resection of more than one segment. We calculated the effective resection ratio and the liver volume increase at the 4th postoperative week to evaluate postoperative hepatic insufficiency. The liver volume increase 4 weeks after surgery correlated significantly with the effective resection ratio and also showed an inverse correlation with the severity of chronic changes in the liver. The liver volume increase also inversely correlated with the preoperative retention of indocyanine green at 15 min. Patients with postoperative hepatic insufficiency tended to show a smaller liver volume increase than expected for their resection ratio. In contrast, noncirrhotic patients had no such particular tendency. In conclusion, measurement of the liver volume using this technique appears to be a simple and useful method to evaluate liver volume after resection; as such, it may also be used to evaluate hepatic regeneration after resection.


Cancer Chemotherapy and Pharmacology | 1989

Liver resection using a water jet

Yoshie Une; Junichi Uchino; Takashi Horie; Yuji Sato; Kazuhiro Ogasawara; Akira Kakita; Fumio Sano

SummaryThe water-jet method has been used during hepatic resection. The instrument cuts the hepatic tissue with the high pressure of the fine water flow, while the exposed elastic intrahepatic vessels are spared injury. A comparative study on the water-jet method with the previously employed conventional methods was undertaken. Hepatic resections were performed on 35 patients using the water-jet method. Cirrhosis of the liver was associated with 10 of the 24 patients with hepatocellular carcinoma. An ordinary saline solution was used as the jet, which was projected at a pressure of between 12 kg/cm2 and 20 kg/cm2 through a 0.15/mm-diameter nozzle. A higher jet pressure was needed to cut the fibrotic hepatic parenchyma. In the case of normal liver, the intrahepatic vessels of more than 0.2 mm were well preserved. In most of the cases, the loss of blood when cutting the hepatic parenchyma can be easily reduced with a jet pressure of 15–16 kg/cm2, thus preserving the fine vessels more than 0.2 mm in diameter without injury. When the same pressure was applied in the cutting of a cirrhotic liver, it took much longer time compared to that of a non-cirrhotic normal liver parenchyma. The cut surface was smooth compared to that after using CUSA, although its disadvantages lie in the formation of air bubbles, which obscure the operative field. The controlled projection of a jet of water under optimal pressure may ensure a safe hepatic resection of both normal and cirrhotic livers. Furthermore, because of its uncomplicated form, a wide range of applications can be expected, while the lower cost will also expedite its large-scale use for economic reasons.


Surgery Today | 1994

Treatment of lymph node recurrence in patients with hepatocellular carcinoma

Yoshie Une; Kazuhito Misawa; Tsuyoshi Shimamura; Kazuhiro Ogasawara; Yoshihiro Masuko; Naoki Sato; Yasuaki Nakajima; Junichi Uchino

The clinicopathological features and results of lymph node dissection were investigated in four patients with hepatocellular carcinoma (HCC) who developed lymph node recurrence following hepatectomy. One patient was found to have metastasis in the periportal lymph nodes at the time of a second laparotomy, while the other three developed posterior pancreaticoduodenal lymph node metastasis. All four patients had concomitant cirrhosis of the liver and were negative for hepatitis B surface antigen. No relationship between the site of the primary lesion and the location of lymph node metastasis was found. Two of the four patients are alive and in good health 4 years and 3 months, and 7 years and 3 months after their first operation, respectively. Thus, we conclude that the posterior pancreaticoduodenal lymph nodes are the most common site of lymph node recurrence of HCC, and that dissection of the affected lymph nodes offers the best chance of longterm survival.


World Journal of Surgical Oncology | 2015

Macro- and microscopic findings of ICG fluorescence in liver tumors

Shingo Shimada; Seiji Ohtsubo; Kazuhiro Ogasawara; Mitsuo Kusano

BackgroundReports detailing microscopic observations of indocyanine green (ICG) fluorescence imaging (IFI) in hepatocellular carcinoma (HCC) and metastatic liver cancer are rare. We were able to perform macro- and microscopic IFI results in postoperative paraffin-embedded tissue samples and formalin-fixed specimens from liver tumors.MethodsBetween April 2010 and March 2014, 19 patients with HCC or liver metastases of colorectal tumors underwent liver resection. ICG solution was injected into the peripheral vein from 14 to 2 days prior to operation. We observed liver tumor IFI during the laparotomy and IFI in resected liver sections using a photo dynamic emission (PDE) camera. The IFI of paraffin-embedded tissue samples was observed using a charge-coupled device (CCD) camera. Moreover, we microscopically performed tissue section IFI using a fluorescence microscope with an ICG-B-NQF.ResultsWe performed that IFI characteristics depended on tumor type macroscopically and microscopically. In normal liver tissue, fluorescence consistent with the bile canaliculus was observed. HCC had heterogeneous IFI, forming a total or partial tumor and rim pattern. In metastatic carcinoma, we performed that non-tumor cells in the marginal region showed fluorescence and tumor cells in the central region did not fluoresce.ConclusionsWe confirmed that the variations of ICG fluorescence imaging patterns reflect different tumor characteristics in not only macroscopic imaging as previous reports but also microscopic imaging. Moreover, the ICG fluorescence method is useful for postoperative pathological detection of microscopic lesions in histopathological specimens. ICG fluorescence in paraffin-embedded tissue samples and formalin-fixed specimens is preserved in the long term.


Archive | 1992

Treatment of recurrent primary liver cancer

Junichi Uchino; Yoshie Une; Yasuaki Nakajima; Naoki Sato; Shinichi Matsuoka; Toshiya Kamiyama; Kazuhito Misawa; Hiroyuki Ishizu; Kazuhiro Ogasawara

Resection of the liver offers the most favorable prognosis for primary liver cancer (PLC) [1]. Recently, an increasing number of patients with hepatocellular carcinoma (HCC) have been treated with resection, and the survival periods have been prolonged. However, the rate of recurrence after resection is still high, and there is much room for improvement. [2–5].


Journal of Hepato-biliary-pancreatic Surgery | 1997

Preoperative percutaneous transhepatic portal embolization with absolute ethanol in patients with hepatocellular carcinoma

Yoshie Une; Tsutomu Haneda; Kazuhiro Ogasawara; Tsuyoshi Shimamura; Michiaki Matsushita; Kazuaki Nakanishi; Yasuaki Nakajima

Preoperative percutaneous transhepatic portal vein embolization (PTPE) has been used in recent years to decrease the amount of liver resected and to reduce the risk of postoperative liver failure in patients with hepatocellular carcinoma. Various thrombogenic agents have been employed for this purpose. We evaluated the clinical safety and efficacy of absolute ethanol for PTPE and examined the histopathologic changes that follow ethanol embolization of the liver. We studied nine patients with hepatocellular carcinoma who were not originally regarded as surgical candidates because of a high risk of postoperative liver failure. They received preoperative PTPE of the right portal vein, with an average of 22.8 ml of absolute ethanol. The right lobe showed complete obstruction of portal venous branches and massive necrosis of the liver parenchyma. Macroscopically, there was atrophy of the embolized lobes and compensatory hypertrophy of the remaining lobes. The mean volume of the nonembolized lobe increased, from 351 to 585 and 633 ml, 2 and 4 weeks after embolization, respectively. The mean regeneration rate of this lobe was 16.7 cm3/day for the first 2 weeks after embolization and 10.1 cm3/day for the first 4 weeks. Transient dynamic increases in alanine aminotransferase concentrations were seen. All patients subsequently underwent right lobectomy of the liver and survived without severe complications. Portal vein embolization with absolute ethanol makes more extensive hepatectomy possible by reducing the volume necessary to resect, and it preserves the function of the remaining liver.


Surgery Today | 2001

Primary Lung Cancer Occurring Concomitantly with the Cicatrized and Calcified Ova of a Parasite: Report of a Case

Takeshi Hanagiri; Ichiro Tsuda; Tetsu Tsukamoto; Tomokazu Nagasako; Hiroaki Kobayashi; Masahiro Hattori; Katsuyoshi Kawamura; Kazuhiro Ogasawara; Kunihiko Manabe; Junichi Uchino

Abstract We report herein a rare case of primary lung cancer that occurred concomitantly with the calcified ova of a parasite. A 58-year-old man was referred to our department after a pulmonary abnormal shadow had been seen on a chest X-ray done at mass screening. A transbronchial lung biopsy (TBLB) revealed the calcified ova of a parasite. Because the possibility of concomitant lung cancer could not be ruled out, a lung biopsy was taken via video-assisted thoracic surgery (VATS). The pathological diagnosis was squamous cell carcinoma, and a left upper lobectomy was serially performed through a posterolateral thoracotomy. The patient recovered uneventfully and has remained in good health without any sign of recurrence for over 9 months. Following this case report, we review three other cases of this unusual disease combination documented in the literature.


Hepatology | 1996

Selective portal vein embolization with absolute ethanol induces hepatic hypertrophy and makes more extensive hepatectomy possible

Kazuhiro Ogasawara; J Uchino; Yoshie Une; Yasunori Fujioka

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