Hiroyuki Iwasaki

International University of Health and Welfare, Atami, Shizuoka-ken, Japan

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Publications (28)33.17 Total impact

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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: 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.
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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. · 7.19 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. · 3.11 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. On a revu les dossiers de 108 cas de tumeur de cellules de Hürthle de la thyroïde (HCT) observées entre 1982 et 1996. II y avait 160 femmes et 28 hommes avec un âge moyen de 51.8 ans. Trente et un patients avaient un cancer alors que les autres avaient un adénome. L’âge, la taille de la tumeur primitive et le taux de thyroglobuline préopératoire ne différaient pas de facon significative entre les patients ayant un cancer ou un adénome. Le sexe ratio, cependant, différait de façon significative (p<0.05). On a observé une récidive de tumeur de cellules de Hürthle chez trois patients ayant un adénome. Deux patients avaient une récidive sous-cutanée, probablement par implantation, alors que le troisième avait une récidive au niveau du moignon thyroïdien. Tous les patients ayant une récidive d’adénome ont eu une lobectomie partielle au moment de l’intervention initiale. Trois patients ont eu une récidive. On a observé une récidive locorégionale chez un patient et des métastasesà distance chez deux patients (poumon n=1, os, n=1). Un seul ayant des métastasesà distance est décédé. L’implantation tumorale a été observée chez les patients ayant un adénome et ainsi, la manipulation de la tumeur en peropératoire semble être un facteur important. II va de soi, également, que la tumeur, même si elle est bénigne, est agressive en termes d’activité proliférative. Tous les patients ayant une HCT doivent être traités, au moins, par lobectomie totale. L’évolution des patients ayant un cancer n’était pas aussi péjorative que rapporté antérieurement. Se revisan entre 1982 y 1996, 188 casos de tumores de tiroides con células de Hürthle (HCT). 160 eran mujeres y 28 hombres con edad media de 51.8 anõs. Se registraron 31 casos de cánceres, siendo los restantes adenomas. La edad, el tamanõ del tumor primario y los niveles preoperatorios de tiroglobulina no mostraron diferencias significativas entre los cánceres y los adenomas. Sin embargo, la incidencia por lo que al sexo se refiere fue muy significativa (p<0.05). Recidiva del HCT se constató en 3 pacientes con adenomas. Dos presentaron recidivas subcutáneas (sospechosas de implantación celular) y otro enfermo desarrolló la recidiva en tejido glandular residual del tiroides. En todos los pacientes con recidiva adenomatosa se habia efectuado, como operación inicial, una lobectomia. Tres enfermos con cáncer recidivaron; recidiva loco-regional se observó en uno y metástasis a distancia en dos (una pulmonar y otra ósea); uno de los pacientes con metástasis a distancia falleció; el otro vive con su enfermedad. Implantación tumoral se constató en pacientes con adenoma por lo que la manipulación intraoperatoria de estos tumores requiere sumo cuidado. Este hecho demuestra que los HCT aunque sean benignos son agresivos por lo que a su actividad proliferativa se refiere. En todos los pacientes con HCT debe realizarse al menos una lobectomia total. Los resultados en pacientes con cáncer no fueron tan malos como los referatados en trabajos previos.
    World Journal of Surgery 09/2001; 25(9):1160-1163. · 2.35 Impact Factor
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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. · 2.35 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. · 1.21 Impact Factor
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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. · 0.91 Impact Factor
  • K 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 01/1998; 21(7):445-8. · 1.55 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. · 2.35 Impact Factor
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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. · 1.55 Impact Factor
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    ABSTRACT: To investigate the biological characteristics of papillary thyroid carcinoma from the perspectives of lymph node metastasis, lymph node recurrence, and distant metastasis, 746 patients with nonadvanced papillary thyroid carcinoma were retrospectively studied. There were 76 men and 670 women with a mean age of 42.7 years. The rate of lymph node metastasis was significantly higher in young patients (aged less than 30 years). Lymph node recurrence was observed in 80 patients and distant metastasis in 13, being seen with significant frequency in the young and elderly (aged over 50 years) patients and in the men. The frequency of distant metastasis was significantly greater in the elderly patients and in those with lymph node recurrence. These findings indicate that the role of regional lymph nodes and the clinical meaning of lymph node recurrence differ between young and elderly patients.
    Surgery Today 02/1995; 25(4):324-8. · 1.21 Impact Factor
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    ABSTRACT: Prerequisites for surgical treatment of Graves' disease are that it can be done safely and that it is associated with a low incidence of recurrent hyperthyroidism. Early recurrence is especially undesirable. We studied 728 patients with Graves' disease treated by subtotal thyroidectomy using multivariate analysis in order to determine the factors related to early recurrence. The following factors were analyzed: age, sex, duration of medical treatment, weight of resected thyroid tissue, thyroid remnant size, preoperative level of thyroid-stimulating hormone (TSH) binding inhibitory immunoglobulin (TBII), and antimicrosomal hemagglutination antibody (MCHA). "Early recurrence" was defined as TSH suppression observed within the first year after surgery and continuing for at least 6 months. A total of 106 patients (14.6%) had early recurrence. Statistical analyses were performed by the chi-square test for univariate analysis and a logistic model for multivariate analysis. Significant factors were thyroid remnant size, MCHA, and TBII. These results indicated that TBII and MCHA are related to early recurrence of hyperthyroidism, and smaller remnant size is recommended for patients with a high MCHA titer or a high TBII level (or both) in order to avoid early recurrence.
    World Journal of Surgery 01/1995; 19(4):648-52. · 2.35 Impact Factor
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    ABSTRACT: We report herein the case of a 56-year-old man found to have an isolated dissecting aneurysm of the superior mesenteric artery (SMA) after he presented with a 3-day history of postprandial epigastralgia of sudden onset. An echogram showed marked dilatation of the SMA and a high level of peripheral echoes in a linear fashion within its lumen. A thin-section contrast enhanced computed tomography revealed a thin flap, separating two distinct well-enhanced lumina. Angiography confirmed the presence of a localized dissecting aneurysm of the SMA. The patient was treated conservatively and has since been followed up as an outpatient. Following the presentation of this case, the problems regarding the diagnosis and management of this rare disease are discussed based on a review of the literature.
    Surgery Today 02/1994; 24(10):933-6. · 1.21 Impact Factor
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    ABSTRACT: We experienced a very rare case of hyalinizing trabecular adenoma of the thyroid. The histopathological features of this case included the following. 1) In puncture-aspiration cytodiagnosis, tumor cells aggregated around pink-stained hyaline acellular areas in an ellipsoidal or spindly configuration, with a part of the cytoplasm appearing as filamentous with unclear borders. In addition, a large number of intranuclear "holes" and nuclear grooves were evident. 2) In biopsy, tumor cells appeared in ellipsoidal or spindly configuration, with cytoplasm that easily stained with thyroglobulin but did not stain with calcitonin. The nuclei were irregular in size and some of the nuclei appeared strongly atypical, occasionally seen with cytoplastic inclusion body in the nucleus. These cells showed funicular structures in a radical arrangement with a hyaline material at the center. The hyaline material was stained positively with PAS or Laminin, but not with Cong red.
    Nippon Geka Gakkai zasshi 05/1993; 94(4):416-9.
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    ABSTRACT: We studied histopathologically the infiltrative modes in 17 cases with tracheal infiltration of the thyroid cancer, and studied its excisional range. 1) Macroscopically, morphologies in the regions of the trachea were divided into 3 types. Types I and II were noted in 4 cases for each and Type III was noted in 9 cases. 2) When the infiltrative modes in the trachea were divided into localized and infiltrative types, localized type was noted in all cases of type I, and infiltrative type was noted in all cases of Type II. The both types were noted in 2 cases and 7 cases of Type III, respectively. 3) Infiltrative region of the tracheal mucous membrane in all cases of Types I and III was localized in the range of the infiltrative region of the extratracheal mucous membrane. The infiltrative region of the tracheal mucous membrane was wider in 2 cases of Type II comparing with that of the extratracheal mucous membrane. It is considered that radical treatment of types I and III can be obtained by the excisional range of the infiltration of the extratracheal mucous membrane. Operative diagnosis is necessary because wider range infiltration of the cancer is observed in the tracheal mucous membrane of Type II.
    Nippon Geka Gakkai zasshi 01/1992; 92(12):1694-9.
  • K Sugino, Y Kure, H Iwasaki, A Matsumoto
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    ABSTRACT: Bone mineral content of 38 thyroidectomized patients with well differentiated thyroid carcinoma were determined. Seventeen patients were totally thyroidectomized and 21 patients were non-totally thyroidectomized (lobectomy). Thirty-eight healthy males and females were served as age-matched controls. Trabecular bone mineral content of lumbar vertebra was evaluated by quantitative CT method. Bone metabolic parameters in serum were measured. No significant differences were observed in the mean bone mineral content and BMC-index of totally thyroidectomized patients compared with non-totally thyroidectomized patients and control. Serum calcitonin level was not reduced in totally thyroidectomized. It is concluded that after total thyroidectomy, bone metabolic disturbance was not significant, and that when calcitonin remained at its basal level, it had no effects on bone metabolism.
    International surgery 01/1992; 77(3):178-80. · 0.25 Impact Factor
  • The journal of the Japanese Practical Surgeon Society. 01/1991; 52(10):2346-2350.

Publication Stats

486 Citations
33.17 Total Impact Points


  • 2013
    • International University of Health and Welfare
      • Department of Surgery
      Atami, Shizuoka-ken, Japan
  • 1992–2003
    • Yokohama City University
      • Department of Medicine
      Yokohama, Kanagawa, Japan
  • 1988–2003
    • Ito Hospital
      Edo, Tōkyō, Japan