Hiroyuki Iwasaki

International University of Health and Welfare, Otahara, Tochigi, Japan

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Publications (39)40.86 Total impact

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    ABSTRACT: Background and AimThe feasibility of TDM-621, the synthetic infectious agent-free peptides, was tested in hemostasis of the bleeding after endoscopic treatments of the gastric tumors. Methods The patients who underwent endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) were enrolled in the present study. The subject of hemostasis was the oozing after the EMR or ESD. The hemostatic effect, the secondary hemorrhage from one postoperative day to the day before discharge and operability were studied. ResultsThe hemostatic effects were assessed in 12 patients. It was remarkably effective in 11 patients and effective in 1 patient. The operability was very easy in two patients, easy in eight patients and acceptable in two patients. No secondary hemorrhage was observed in all of 12 patients. No adverse effect considered to be related to TDM-621 was observed. Conclusion It was shown that hemostasis using TDM-621 was feasible after endoscopic treatments of the gastric tumors without any technical trouble or adverse event.
    Journal of Gastroenterology and Hepatology 12/2014; 29(Suppl 4):77-79. DOI:10.1111/jgh.12798 · 3.50 Impact Factor
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    ABSTRACT: We treated three postmenopausal female patients with unresectable local recurrence from breast cancer. All pathological diagnoses of the local recurrence lesions were ER-positive breast cancer. For treatment, we administered anastrozole to these three patients. One has been stable disease for 25 months after taking anastrozole. Another has also showed stable disease for 18 months, and the last patient has been a partial response. We performed a biopsy from a recurring lesion on these three patients, and made a diagnosis of ER-positive breast cancer. This strategy of unresectable local recurrence revealed that these three patients could have had a stable condition for a long duration by taking anastrozole.
    Gan to kagaku ryoho. Cancer & chemotherapy 03/2013; 40(3):361-363.
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    ABSTRACT: For precision improvement of breast cancer examinations and additional workup, we examined Category 3, 4 and 5 mammography cases at our hospital. We included 1,624 women who underwent mammography during a one-year period from August 2008 to July 2009. Categories 1 and 2 accounted for 1,458 cases (89%). Category 3 accounted for 128 cases (7.9%), Category 4 33 cases (2.0%), and Category 5 11 cases (0.6%). Breast cancer was found in 5.4% of Category 3 cases, 54% of Category 4 cases, and 100% of Category 5 cases. This indicated that the category classification used for mammography interpretation at our institution was appropriate. Additional workup was performed on the basis of the findings, and the category was judged to be adequate. However, one problem was the large number of Category 3 and 4 cases for which it was unclear whether additional workup was necessary.
    Nihon Nyugan Kenshin Gakkaishi (Journal of Japan Association of Breast Cancer Screening) 01/2011; 20(2):135-138. DOI:10.3804/jjabcs.20.135
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    ABSTRACT: In May 2006, a 79-year-old man underwent left colectomy and D2 lymphadenectomy for descending colon cancer (fStage II , Cur A). No adjuvant chemotherapy was done. Eighteen months after surgery, the serum tumor marker level was increased (CA19-9 526 U/mL), and multiple liver metastases (H2) and peritoneal dissemination were detected using abdominal CT. He was treated with S-1 plus CPT-11 therapy, because mFOLFOX6 as a standard chemotherapy for advanced colorectal cancer was rejected. After 4 courses, tumor markers normalized and abdominal CT revealed a partial response. At present, progression-free survival (PFS) is 240 days. In our case, this regimen was found to be convenient and safe in an outpatient compared with FOLFIRI and FOLFOX. This case suggested that S-1 plus CPT-11 therapy could well be a promising systemic chemotherapy for patients with advanced colorectal cancer.
    Gan to kagaku ryoho. Cancer & chemotherapy 09/2009; 36(8):1371-3.
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    ABSTRACT: We report a case of advanced rectal cancer successfully treated with a combination of S-1 and CPT-11 as neoadjuvant chemotherapy. The patient, a 61-year-old man, had a rectal cancer with pelvic viscera invasion and severe stenosis. After colostomy for removing stenosis, he was treated with a combination of S-1 and CPT-11 (S-1 120 mg/body day on day 1-14, CPT-11 120 mg/body/day on day 1 and day 15, every 4 weeks). Seven courses of treatment resulted in a marked reduction of the primary tumor and disappearance of invasion. Subsequently, rectal amputation for curative intent was done. No surgical complication was observed. On microscopic examination, only a few tumor cells were detected in the granulation tissue of the resected rectum and no tumor cells in dissected LNs. This case demonstrates the effectiveness and safety in a neoadjuvant setting of a combination of S-1 and irinotecan for rectal cancer.
    Gan to kagaku ryoho. Cancer & chemotherapy 11/2007; 34(10):1667-9.
  • Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/2007; 68(5):1206-1210. DOI:10.3919/jjsa.68.1206
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    Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/2005; 66(9):2177-2180. DOI:10.3919/jjsa.66.2177
  • Nippon Shokaki Geka Gakkai zasshi 01/2004; 37(4):440-445. DOI:10.5833/jjgs.37.440
  • Nippon Shokaki Geka Gakkai zasshi 01/2004; 37(11):1787-1793. DOI:10.5833/jjgs.37.1787
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    Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/2004; 65(9):2319-2324. DOI:10.3919/jjsa.65.2319
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    ABSTRACT: To determine the frequency and pattern of lymph node metastasis (LNM) from papillary thyroid microcarcinoma (PTMC) and the results of node dissection, and to establish the optimal strategy for neck dissection in these patients. Most PTMCs carry a favorable prognosis, but a few present with palpable lymphadenopathy. Patients with LNM are at risk for nodal recurrence, although they do not have higher mortality. The frequency and pattern of LNM from PTMC and the results of node dissection are not well established. The frequency and pattern of LNM from 259 PTMCs were analyzed according to the size and location of the primary tumor. Of the 259, 24 with palpable nodes underwent therapeutic node dissection and the other 235 patients without palpable nodes underwent prophylactic node dissection. The authors compared the results of node dissection between the therapeutic group and the prophylactic group, and between PTMCs 5 mm or smaller and PTMCs larger than 5 mm. The authors also compared nodal recurrence between the prophylactic group and a no-lymph-node-dissection group (155 PTMCs). Overall, 64.1% (166/259) and 44.5% (93/209) had node involvement of the central and ipsilateral lateral compartment, respectively. Pretracheal (43.2%), ipsilateral central (36.3%), and ipsilateral mid-lower (37.8%) jugular were more commonly involved. LNM was more frequent in the therapeutic group than in the prophylactic group (95.8% vs. 60.9% for central compartment, 83.3% vs. 39.5% for ipsilateral lateral compartment). Nodal recurrence was more common in the therapeutic group than in the prophylactic group (16.7% vs. 0.43%), but did not differ between the prophylactic group and the no-dissection group (0.43% vs. 0.65%). The tumor size did not influence nodal recurrence. Nodal recurrence preferentially occurred in ipsilateral mid-lower jugular nodes. Patients who have PTMC presenting with palpable lymphadenopathy should have therapeutic node dissection. Prophylactic node dissection is not beneficial in those without palpable lymphadenopathy.
    Annals of Surgery 04/2003; 237(3):399-407. DOI:10.1097/01.SLA.0000055273.58908.19 · 8.33 Impact Factor
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    ABSTRACT: Anaplastic thyroid carcinoma is a rare and highly lethal neoplasm. We investigated whether operations have an impact on the survival of patients who have anaplastic carcinoma without distant metastasis. Between 1989 and 1999, 40 consecutive patients with anaplastic carcinoma, without distant metastasis at the time of presentation or during local treatment, were reviewed. The cumulative survival rates and 1-year survival rates were compared. Eleven patients had a small focus of anaplastic carcinoma in a differentiated carcinoma, and 29 patients had ordinary anaplastic thyroid carcinoma. Surgical debulking was performed in 26 patients. Radiotherapy was used for 31 patients and chemotherapy for 19 patients. The 1-year survival rates of the patients with incidental anaplastic carcinoma, ordinary anaplastic carcinoma who underwent operations, and ordinary anaplastic carcinoma who did not undergo operations were 73%, 60%, and 21%, respectively. A significantly higher cumulative survival rate was observed in patients with incidental anaplastic carcinoma than in those with ordinary anaplastic carcinoma. A significantly better outcome was obtained by surgical debulking of ordinary anaplastic carcinoma. Patients with incidental anaplastic carcinoma tended to have a good outcome, but some had a poor prognosis. Surgical debulking improved the outcome of patients with ordinary anaplastic carcinoma.
    Surgery 04/2002; 131(3):245-8. DOI:10.1067/msy.2002.119936 · 3.38 Impact Factor
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    ABSTRACT: We reviewed 188 cases of Hürthle cell tumor of the thyroid (HCT) between 1982 and 1996. There were 160 women and 28 men with a mean age of 51.8 years. Thirty-one of the patients had cancer, and the others had adenoma. Age, size of the primary tumor, and preoperative thyroglobulin level were not significantly different in the cancer and adenoma patients. The gender ratio, however, was significantly different (p < 0.05). Recurrent HCT was observed in three patients with adenoma. Two patients had subcutaneous recurrence (suspected implantation), and the other patient had recurrence in the residual thyroid gland. All patients with recurrence of adenoma underwent partial lobectomy at the initial operation. Three cancer patients had recurrent disease. Locoregional recurrence was observed in one patient and distant metastases in two patients (lung in one, lung and bone in one). One of the patients with distant metastasis died from the disease, and the other is alive with the disease. Tumor implantation was observed in patients with adenoma, so intraoperative handling of the tumor requires care. It also means that this tumor, even though benign, is aggressive in terms of proliferative activity. All patients with Hürthle cell tumor should be treated by total lobectomy at least. The outcome of the cancer patients was not as poor as in previous reports.
    World Journal of Surgery 09/2001; 25(9):1160-1163. DOI:10.1007/BF03215865 · 2.64 Impact Factor
  • Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/2001; 62(4):889-893. DOI:10.3919/jjsa.62.889
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    ABSTRACT: Thyroid-stimulating hormone (TSH)-binding inhibitory immunoglobulin (TBII) is thought to be one of the essential causes of Graves' disease, and most cases of neonatal hyperthyroidism can be explained by transplacental passage of TBII. Because surgery is often indicated for patients of childbearing age, it is important to elucidate how surgery reduces TBII levels. Between 1988 and 1991 a total of 946 female patients with Graves' disease underwent subtotal thyroidectomy. Follow-up examination was undertaken at 1, 2, 3, and 4 to 5 years after surgery. At 4 to 5 years after surgery, 76.8% of patients without recurrent overt hyperthyroidism had TBII < 20%. In patients with recurrent hyperthyroidism, TBII increased gradually during follow-up, and they had higher TBII levels than nonrecurrence patients. There were a few euthyroid and hypothyroid patients who had TBII > 60%, and the number of such patients decreased annually. In most of the patients, immunologic remission was obtained by subtotal thyroidectomy except for their having recurrent hyperthyroidism. To acquire immunologic remission, hormonal remission, at least, would be necessary. Because no definite factor other than the size of the thyroid remnant related to postoperative thyroid function was elucidated, near-total thyroidectomy rather than subtotal thyroidectomy is expected to be induced not only hormonal remission but also immunologic remission. It should be noted that a few patients achieved hormonal remission but not immunologic remission.
    World Journal of Surgery 07/1999; 23(7):727-31. DOI:10.1007/PL00012377 · 2.64 Impact Factor
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    ABSTRACT: We report herein an extremely rare case of intrathoracic omental herniation through the esophageal hiatus. In fact, according to our review of the literature, only eight other cases have been reported, most of which were misdiagnosed as mediastinal lipoma after being identified as an intrathoracic mass. We report herein the ninth case of intrathoracic omental herniation through the esophageal hiatus. A 54-year-old obese woman was admitted to our hospital for investigation of a chest roentgenographic abnormality. She was asymptomatic, and her physical examination and laboratory data were all within normal limits. Her chest X-ray demonstrated a large, sharply-defined mass, and a computed tomography scan of the thorax indicated a large mediastinal mass with fat density. A thoracotomy was performed under the diagnosis of a mediastinal lipoma which revealed an encapsulated fatty mass, 10x7.5x6 cm in size, that proved to be an omental herniation through the esophageal hiatus. There was no herniation of the stomach or intestines into the thorax. The esophageal hiatus was repaired after the omental mass and hernia sac had been resected. This case report serves to demonstrate that whenever a mass of fat density is recognized in the lower thorax, an omental herniation should be borne in mind as a possible differential diagnosis.
    Surgery Today 02/1999; 29(4):347-50. DOI:10.1007/BF02483060 · 1.53 Impact Factor
  • Y Rino · T Imada · H Iwasaki · H Tanabe · H Toyoda · N Kato · T Amano · J Kondo
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    ABSTRACT: This paper reports a case in which endoscopic hemostasis of a bleeding colonic diverticula was successful with endoscopic hemoclip. The patient, a 53 year-old man with painless hematochezia, was urgently admitted to our institute. After colonic cleaning preparation, colonoscopic examination was performed. At the bottom of the diverticulum of the ascending colon, a vessel with oozing blood was endoscopically noted. Hemoclips were placed on and around the visible vessel and immediate hemostasis was completed. Endoscopic clipping method for management of bleeding diverticular vessel is an effective, simple, and safe procedure.
    Hepato-gastroenterology 01/1999; 46(27):1733-5. · 0.93 Impact Factor
  • Kiminori Sugino · K Ito · O Ozaki · T Mimura · H Iwasaki
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    ABSTRACT: Papillary microcarcinoma of the thyroid has been often detected by aspiration biopsy cytology performed with ultrasonographic guidance. Autopsy studies also have often revealed small thyroid carcinomas, and it was concluded that most small thyroid carcinomas should not be regarded as a clinical matter. In this study, 112 patients with papillary microcarcinoma 10 mm or less in size treated between 1992 and 1995 were analyzed. There were 104 females and 8 males, with a mean age of 46.0 years. Diagnosis of papillary carcinoma was made preoperatively in 100 of these patients (89.3%), and 77 patients underwent aspiration biopsy cytology under ultrasound guidance. Seventy of these patients underwent modified neck dissection, and 63.8% of these patients had lymph node metastases. The number of lymph node metastasis increased as primary tumor size increased. There was no clear border or clinical differences between primary tumors 10 mm or less and tumors more than 10 mm. One patient had lymph node recurrence after surgery and another patient had recurrent nerve palsy at the first visit. Based on these findings, papillary microcarcinoma should be treated surgically.
    Journal of endocrinological investigation 07/1998; 21(7):445-8. DOI:10.1007/BF03347324 · 1.45 Impact Factor
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    ABSTRACT: To make the surgical treatment for Graves' disease more ideal, it is important to elucidate factors related to postoperative thyroid dysfunction in addition to thyroid remnant. Because TSH receptor antibody (TRAb) is thought to be one of the essential causes of Graves' disease, we investigated whether preoperative changes in serum TRAb levels are related to postoperative recurrent hyperthyroidism. Between 1987 and 1992 a total of 1520 patients with Graves' disease were treated by subtotal thyroidectomy. Of these patients 335 visited Ito Hospital with no history of drug treatment of their disease and were treated surgically after several courses of antithyroid drug (ATD) therapy. There were 68 males and 267 females with a mean age of 25.8 years. The mean follow-up period was 48 months (range 12-84 months). Factors analyzed by univariate and multivariate analysis were as follows: age, sex, duration of ATD treatment, weight of resected thyroid, weight of thyroid remnant, preoperative titer of MCHA, TRAb at the time of initial examination (TRAb1), TRAb at the time of surgery (TRAb2), and DeltaTRAb, the difference between TRAb1 and TRAb2 (DeltaTRAb = TRAb1 - TRAb2). The chi-square test was used for univariate analysis and a logistic model for multivariate analysis. Of this group, 119 patients were euthyroid (35.5%), 50 were hyperthyroid (14.9%), and 166 were hypothyroid (49.3%). Significant factors related to recurrent hyperthyroidism were weight of thyroid remnant and DeltaTRAb in both univariate and multivariate analyses. DeltaTRAb is a possible new marker for predicting postoperative recurrent hyperthyroidism. If the preoperative TRAb level is not improved by ATDs in patients with Graves' disease, the thyroid remnant should be made smaller.
    World Journal of Surgery 10/1996; 20(7):801-6; discussion 806-7. DOI:10.1007/s002689900122 · 2.64 Impact Factor
  • Kiminori Sugino · T Mimura · O Ozaki · H Iwasaki · N Wada · A Matsumoto · K Ito
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    ABSTRACT: If the aim of surgical treatment for Graves' disease is not permanent hypothyroidism, it is difficult to avoid recurrent hyperthyroidism completely. The management of recurrent hyperthyroidism, however, is neither easy nor obvious. Improvement in the sensitivity of TSH assay has allowed the diagnosis of latent hyperthyroidism. Little is known about the clinical course of latent hyperthyroidism. We studied the management and outcome of recurrent hyperthyroidism in patients with Graves' disease treated by subtotal thyroidectomy. Between January 1988 and August 1991, 1115 patients with Graves' disease were treated by surgery. Postoperative thyroid function was evaluated by free T3, free T4 and TSH measurements. One hundred seventy-five patients with suppressed TSH secretion for at least 6 months were categorized as having recurrent hyperthyroidism. Eighty patients (45.1%) also had elevated thyroid hormone levels, (group 1). The remaining 95 patients (54.9%) had normal thyroid hormone levels with suppressed TSH values (group 2). In group 1, 58 patients were treated with antithyroid drug (ATD), 12 with iodine and 10 with radioiodine (RI). Remission of Graves' disease was obtained in 22 patients (11 by ATD, 1 by iodine and 10 by Ri). On the other hand, patients in group 2 were followed up without medication, and spontaneous remission was observed in 21 of theln (22.1%). It was difficult to induce remission of overt recurrent Graves' disease by ATD or iodine. In contrast spontaneous remission could be obtained in some patients with postoperative latent hyperthyroidism.
    Journal of endocrinological investigation 07/1995; 18(6):415-9. DOI:10.1007/BF03349738 · 1.45 Impact Factor