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Publications (12)25.82 Total impact

  • Article: A case of cutaneous T cell pseudolymphoma in a patient with Helicobacter pylori infection.
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    ABSTRACT: Cutaneous pseudolymphomas (CPL) are benign cutaneous lymphoproliferative infiltrations of various origin, including among others bacterial infections, viral infections and drugs . Helicobacter pylori has been frequently founded in the stomach of patients with MALT lymphoma. In January 2001, a 43-year-old man was referred to our department because of a 1-month history of itchy erythematous patches, plaques and flat tumors on his body. Histological examination revealed nodular infiltrations composed of lymphocytes, plasma cells and histiocytes with exocytosis of lymphocytes within the epidermis. Molecular analysis of rearrangement of T cell receptor and immunoglobulin heavy-chain genes did not reveal monoclonality. Based on these clinical, laboratory and histopathological data, a diagnosis of cutaneous T cell pseudolymphoma (CTPL) was made. The patient was anti-H. pylori antibody-positive, and was treated with anti-H. pylori combination with the result that all of the tumors had disappeared by January 2002. The patient has maintained complete response up to the last follow-up visit in December 2005.
    Dermatology 02/2006; 213(2):156-8. · 2.05 Impact Factor
  • Article: Evaluation using contrast-enhanced harmonic gray scale sonography after radio frequency ablation of small hepatocellular carcinoma: sonographic-histopathologic correlation.
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    ABSTRACT: To evaluate the usefulness of contrast-enhanced harmonic wideband gray scale sonographic images obtained after radio frequency-induced coagulation necrosis, we compared the morphologic and histopathologic characteristics of the ablated tumors with sonographic images of the tumors. Forty-eight patients with 72 hepatocellular carcinomas with a maximal diameter of 3 cm or less were treated percutaneously using radio frequency ablation. Six treated tumors in 4 patients were resected 1 month after ablation; the remaining 66 treated tumors were evaluated by a biopsy procedure performed with an 18-gauge fine needle 1 month after ablation. The excised tumors and biopsy specimens were then examined by histopathologic methods, and the findings were compared with those obtained on contrast-enhanced harmonic wideband gray scale sonography. Hematoxylin-eosin-stained specimens were inconclusive as to whether cellular viability remained; therefore, cell viability was determined by a positive result after histochemical (lactate dehydrogenase and nicotinamide adenine dinucleotide phosphate-diaphorase) staining. Contrast-enhanced harmonic wideband gray scale sonography after radio frequency ablation showed residual tumor enhancement in 5 (6.9%) of the 72 tumors; the histopathologic results for these 5 tumors were also positive for tumor residue. The remaining 67 tumors (93.1%) did not show any residual tumor enhancement when examined by sonography; however, only 66 tumors did not reveal tumor residue when examined histopathologically. Contrast-enhanced harmonic wideband sonographic imaging provided results that were comparable with histopathologic findings, the criterion standard for diagnosis; the sensitivity and specificity of the sonographic images for the detection of residual tumor tissue in ablated tumors were 83.3% (5 of 6) and 100% (66 of 66), respectively. Contrast-enhanced harmonic wideband gray scale sonography is a potentially useful technique for evaluating the therapeutic effects of radio frequency ablation on hepatocellular carcinoma.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 04/2005; 24(3):273-83. · 1.25 Impact Factor
  • Article: Retrograde transvenous obliteration of gastric varices associated with large collateral veins or a large gastrorenal shunt.
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    ABSTRACT: Balloon-occluded retrograde transvenous obliteration of gastric varices by a microcatheter insertion method was performed in eight patients with large collateral veins or a large gastrorenal shunt. A 3-F microcatheter was selectively inserted into the gastric varices through a 6-F balloon catheter wedged in the left adrenal vein. Selective venography of the gastric varices and injection of the sclerosing agent, a mixture of 10% ethanolamine oleate and iopamidol, through the microcatheter system without occluding the collateral veins was accomplished in one treatment session in all patients. There have been no complications or recurrences of gastric varices in any of the patients during the follow-up period.
    Journal of Vascular and Interventional Radiology 02/2005; 16(1):113-8. · 2.08 Impact Factor
  • Article: [A case of the rupture of gastroduodenal artery aneurysm by penetration to the duodenum, successfully treated with transcatheter arterial embolization].
    Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 06/2004; 101(5):516-20.
  • Article: Contrast-enhanced harmonic gray-scale sonographic-histologic correlation of the therapeutic effects of transcatheter arterial chemoembolization in patients with hepatocellular carcinoma.
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    ABSTRACT: We evaluated the usefulness of contrast-enhanced harmonic wideband gray-scale sonography in the assessment of the therapeutic effects of transcatheter arterial chemoembolization in patients with hepatocellular carcinoma and compared the performance of this imaging modality with the histologic findings for the patients. Twenty-nine patients with 29 hepatocellular carcinoma lesions were examined. Tumor vascularity was evaluated before and 7 days after transcatheter arterial chemoembolization with contrast-enhanced harmonic wideband gray-scale sonography performed after injection of the contrast agent Levovist. Several biopsy specimens were obtained from the evaluated lesions, and the histologic findings were compared with the results of contrast-enhanced sonography. Contrast-enhanced harmonic wideband gray-scale sonography performed after transcatheter arterial chemoembolization showed tumor vascularity in 16 of the 29 lesions, but none in the other 13 lesions. At histologic examination, 13 of the 16 lesions with tumor vascularity had residual tumor revealed, and the 13 lesions without tumor vascularity were found to have no histologically evident tumor residue, although three of these lesions showed tumor progression detected on CT during a 9- to 12-month follow-up period. Contrast-enhanced harmonic wideband gray-scale sonographic images were compared with the histologic findings as the gold standard, and the sensitivity and specificity of these images for discerning viable and nonviable hepatocellular carcinoma after transcatheter arterial chemoembolization were 100% and 81%, respectively. Contrast-enhanced harmonic wideband gray-scale sonography is potentially useful for evaluating the therapeutic effects of transcatheter arterial chemoembolization on hepatocellular carcinoma.
    American Journal of Roentgenology 08/2003; 181(1):65-9. · 2.78 Impact Factor
  • Article: [A case of AFP-producing gastric cancer with multiple liver metastases responding to CPT-11 and cisplatin combination chemotherapy].
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    ABSTRACT: A case of AFP-producing gastric cancer successfully treated with CPT-11 and cisplatin combined therapy is reported together with a review of the literature. A 52-year-old male was admitted with complaints of upper abdominal pain and body weight loss. Gastric cancer with multiple liver metastases was diagnosed based on endoscopy and computed tomography findings. The patient's serum AFP level was 697,100 ng/ml and a biopsy specimen showed AFP-positive tumor cells immunohistochemically. He was treated with a combination chemotherapy consisting of CPT-11 (70 mg/m2) on day 1 and 15, and cisplatin (80 mg/m2) on day 1, repeated every 4 weeks. The primary lesion of the stomach and the liver metastases were remarkably reduced, and the serum level of AFP decreased to 18 ng/ml after 5 cycles of this treatment. No severe side effects were seen during this treatment. This result suggests that combination chemotherapy consisting of CPT-11 and cisplatin may be effective and safe for patients with AFP-producing gastric cancer with multiple liver metastases.
    Gan to kagaku ryoho. Cancer & chemotherapy 12/2002; 29(11):1985-8.
  • Article: Hepatocellular carcinoma: therapeutic experience with percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography with the contrast agent Levovist.
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    ABSTRACT: To describe our experience with percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography with Levovist (SH U 508A; Nihon Schering, Osaka, Japan) for hepatocellular carcinoma after transcatheter arterial infusion. Twenty patients (17 men and 3 women; mean age, 58.4 years) with 23 hepatocellular carcinoma nodules (mean +/- SD, 2.7 +/- 1.5 cm) underwent percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography 1 week after transcatheter arterial infusion. Therapeutic effects were assessed by contrast-enhanced computed tomography and posttreatment fine-needle biopsy. This study was performed on a prospective basis. After the transcatheter arterial infusion, contrast-enhanced color Doppler sonography showed intense intratumoral color signals in all 23 hepatocellular carcinomas. After the percutaneous ethanol injection, contrast-enhanced color Doppler sonography, fine-needle biopsy, and contrast-enhanced computed tomography showed no color signals, no viable tumor tissues, and no enhancement in any of the 23 hepatocellular carcinomas. Three to 5 (mean, 3.3) percutaneous ethanol injection sessions with a 5.2- to 15.6-mL (mean, 12.8-mL) total volume of ethanol per tumor were required for complete disappearance of color signals on contrast-enhanced color Doppler sonography. Percutaneous ethanol injection under real-time contrast-enhanced color Doppler sonography has considerable efficacy in treating hepatocellular carcinoma.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 10/2002; 21(9):1015-22. · 1.25 Impact Factor
  • Article: Radiofrequency ablation in a pig liver model: effect of transcatheter arterial embolization on coagulation diameter and histologic characteristics.
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    ABSTRACT: To determine whether transcatheter arterial embolization (TAE) can alter radiofrequency (RF)-induced coagulation necrosis, we evaluated the morphology and histologic characteristics of RF ablation lesions combined with TAE in normal pig liver. Using a RF ablation system, consisting of a RF generator and 2-cm expandable LeVeen needle electrodes, nine lesions were generated by RF ablation combined with TAE and 11 lesions by RF ablation alone in five animals. On completion of treatment, the lesions were excised for gross and histologic examination. Gross examination demonstrated a core of ablated tissue surrounded by a narrow rim of hemorrhagic necrosis. The final shape of the lesion in the RF ablation group was frequently altered by patent intrahepatic vessels at the periphery of the lesion, whereas the lesions in the RF ablation and TAE group were spherical (P<0.05, chi(2)-test). The coagulation diameter was significantly larger in the RF ablation and TAE group than in the RF ablation group (28.7+/-4.2 vs. 24.1+/-3.2 mm, P<0.05). Histochemical (lactate-dehydrogenase, maleate-dehydrogenase and NADPH-diaphorase) stainings showed what appeared to be 100% cellular destruction in the ablated lesion and its hemorrhagic rim in both groups. We conclude that RF ablation combined with TAE induces greater and more spherical areas of coagulation necrosis in normal pig liver tissue than RF ablation alone.
    Hepatology Research 10/2002; 24(2):164. · 2.20 Impact Factor
  • Article: Treatment of hepatocellular carcinoma with radiofrequency ablation: radiologic-histologic correlation during follow-up periods.
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    ABSTRACT: To determine whether radiographic images after radiofrequency (RF)-induced coagulation necrosis are correlated with the pathologic effects, we evaluated the morphology and histologic characteristics of RF ablation lesions over a 6-month follow-up period and compared the results with those of radiologic studies. Thirty-three hepatocellular carcinoma (HCC) tumors with a maximum diameter of 3 cm or less were treated percutaneously by using RF ablation in 26 patients. Six treated tumors were resected 4 weeks after ablation; the remaining 27 treated tumors underwent a biopsy procedure by using an 18-gauge fine needle 3 days, 4 weeks, and 24 weeks after ablation. The excised or biopsied lesions were examined by using histologic methods; the findings were then compared with those of contrast-enhanced computed tomography (CT). Three days after ablation, a core of hypoattenuation surrounded by an enhanced/hemorrhagic rim was observed on the contrast-enhanced CT images. Hematoxylin-eosin-stained specimens were inconclusive as to whether or not cellular viability remained; however, cell viability as determined by the presence of histochemical (lactate-dehydrogenase, maleate-dehydrogenase, and the reduced form of nicotinamide-adenine dinucleotide phosphate [NADPH]-diaphorase) stains was absent, suggesting 100% cellular destruction in the ablated lesion. Four and 24 weeks after ablation, the sizes of the ablated lesions were progressively smaller on the CT images; the histochemical stains remained superior to the hematoxylin-eosin stains for obtaining a definite diagnosis of cell death. We conclude that irreversible cellular destruction, as determined by the absence of positive histochemical staining patterns, was useful for evaluating the pathologic thermal effect of RF ablation. These pathologic findings can be correlated with those of contrast-enhanced CT.
    Hepatology 07/2002; 35(6):1467-75. · 11.66 Impact Factor
  • Article: Small hepatocellular carcinoma: therapeutic effectiveness of percutaneous radio frequency ablation therapy with a LeVeen needle electrode.
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    ABSTRACT: To evaluate the therapeutic effectiveness of percutaneous radio frequency ablation of small (< or =3-cm) hepatocellular carcinoma with a LeVeen needle electrode. Thirty patients (mean age, 65.7 years) with 32 hepatocellular carcinomas (range, 1.2-3.0 cm; mean, 2.3+/-0.5 cm) underwent percutaneous radio frequency ablation to the center of the hepatocellular carcinoma after expansion of the inner needles. The manufacturer's recommended radio frequency ablation protocol was used. Posttreatment contrast-enhanced color Doppler sonography, contrast-enhanced computed tomography, and fine-needle biopsy were performed to assess the radio frequency ablation-induced coagulated necrosis. Severe intratreatment pain made us abort radio frequency ablation in 2 patients. Complete tumor necrosis was achieved in 1 treatment session with 1 needle electrode insertion in 28 (93.4%) of 30 nodules (28 patients). We found no residual focus on both color Doppler sonography and computed tomography after any of the sessions. In follow-ups ranging from 3 to 15 months (mean, 8.4 months), no local recurrence was found in cases with complete tumor ablation. Radio frequency ablation with the LeVeen needle electrode was effective, obtaining complete coagulated necrosis with a safety margin when used for the treatment of small hepatocellular carcinomas.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 01/2002; 21(1):67-76. · 1.25 Impact Factor
  • Article: Hepatocellular carcinoma: percutaneous radiofrequency ablation using expandable needle electrodes and the double-insertion technique.
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    ABSTRACT: The authors present a case of percutaneous radiofrequency ablation for the treatment of a confirmed hepatocellular carcinoma using expandable needle electrodes and the double-insertion technique. The patient underwent radiofrequency ablation for a 5.0-cm-in-diameter hepatocellular carcinoma in liver segment VIII. One radiofrequency ablation session using the double-insertion technique was performed, resulting in the complete necrosis of the tumor. A collection of pleural effusion as a complication of radiofrequency ablation was revealed by a computed tomography scanning which was performed after the radiofrequency ablation session. However, no other serious complication was encountered. No local recurrences have been observed after a 10-month follow-up period. The present case suggests the therapeutic efficacy of radiofrequency ablation using expandable needle electrodes and the double-insertion technique.
    Hepato-gastroenterology 49(48):1481-3. · 0.66 Impact Factor
  • Article: Hepatocellular carcinoma: a case of extrahepatic seeding after percutaneous radiofrequency ablation using an expandable needle electrode.
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    ABSTRACT: A 2.5-cm diameter, exophytic seeding of hepatocellular carcinoma was detected by contrast-enhanced computed tomography in a 76-year-old man. He had previously undergone a radiofrequency ablation therapy with an expandable, ten-hook needle electrode for the treatment of a 1.5-cm hepatocellular carcinoma in liver segment VI. Ultrasound-guided fine needle biopsy revealed that this hepatocellular carcinoma was moderately differentiated, as initial tumor was. An additional radiofrequency ablation achieved complete ablation of this neoplastic mass on contrast-enhanced computed tomography scanning. Recurrences were not found for eight months after. To prevent tumor seeding, using thermocoagulation when retracting the needle electrode may be useful.
    Hepato-gastroenterology 49(46):897-9. · 0.66 Impact Factor