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Kazuo Shimizu

Publications and source records attributed to Kazuo Shimizu.

At least 91 records · Page 5Linked to original sources
PubMed2003

[Endocrine surgery: the tenth report. Diagnosis, surgical indications and operative strategy of renal hyperparathyroidism].

In Japan, there are many dialysis patients because of the successful development and wide application of dialysis techniques. Almost all patients require long-term hemodialysis treatment because kidney transplantation is performed rarely. Renal hyperparathyroidism is one of the serious complications for hemodialysis patients. According to the overview of regular dialysis treatment reported by the Japanese Society for Dialysis Therapy, parathyroidectomy is required in 9.2%of patients who remain on hemodialysis more than 10 years and in 33.5%of those who so remain for more than 25 years. In this paper, we will describe the diagnosis, surgical indications, and operative strategy of renal hyperparathyroidism. The symptoms and biochemical variables were high serum parathyroid hormone (PTH) level, hyperphosphatemia, bone and joints pain, itching, irritability, muscle weakness, severe skeletal deformity, progression of ectopic calcification, and anemia. The clinical indications for performing parathyroidectomy to treat renal hyperparathyroidism in our institute are based on the indications reported by Tominaga et al. These are 1) high serum PTH level, 2) detection of enlarged parathyroid glands, 3) detection of osteitis fibrosa cystica on radiography or detection of high bone turnover by bone metabolic markers or bone scintigram, 4) resistance of symptoms to medical treatment. The routine operative procedure for renal hyperparathyroidism is total parathyroidectomy with forearm autograft. For autotransplantation, 30 pieces sliced 1x1x3 mm of diffuse hyperplasia are implanted into 30 pockets in the forearm without arteriorvenous (A-V) fistula for hemodialysis. In any surgical procedure for renal hyperparathyroidism, it is crucial to identify all parathyroid glands, including supernumerary glands and ectopic glands. At the initial operation for renal hyperparathyroidism, the surgeon must remove all parathyroid glands to avoid persistent and recurrent hyperparathyroidism and choose proper and adequate parathyroid tissue for autograft.

Humans↗
PubMed2003

Surgical therapy in Hashimoto's thyroiditis.

Hashimoto's thyroiditis (HT) is usually considered to be manageable by levothyroxine (L-T4) administration, which can reduce the thyroid volume and supplement the lack of hormone. However, we sometimes encounter a huge goiter that has not shrunk in response to L-T4 therapy. These goiters continue to produce symptoms of compression and an unsightly appearance. Here we discuss the surgical indication and procedure for HT. Thirteen patients with clinically diagnosed Hashimoto's thyroiditis involving a huge diffuse goiter that produced pressure symptoms or nodular lesions were treated with surgery. The gender, age distribution, total dose and period of L-T4 administration prior to the operation, and clinical symptoms caused by the large goiter were evaluated in each case. The titer of antibodies was extremely elevated in 8 HT patients with a diffusely enlarged goiter. The total period of L-T4 medication ranged from 6 to 25 years. A subtotal thyroidectomy in which a small amount of thyroid was left in the posterior area of the bilateral lobes was performed in the 8 cases of diffusely enlarged goiter. Pressure symptoms and the unsightly appearance caused by the goiter were relieved by the surgery in all cases. No surgical complications developed. In conclusion, the surgery is an effective therapy for HT patients who have persistent compression symptoms and/or an unsightly neck appearance due to a large goiter despite long-term L-T4 treatment.

Aged↗
PubMed2003

[A report of questionnaire survey asking teaching staff concerning evaluation of faculty teaching from the students in Nippon Medical School].

A questionnaire survey was conducted to ask teaching staffs about the present activities and opinions of evaluation of faculty teaching from the students (EFS). One hundred and eighty-eight among 336 members (56.1%) responded. Among them sixty-four (34%) replied that they had tried at least once EFS of their lectures and/or practices. Approximately 70% had a opinion that EFS would benefit them for improving their lectures and practices, and/or for improving course planning. Fifty-four per cent of members supported EFS to be introduced, 34% depended upon how to evaluate, and remaining 5% did not support it. These results indicate that the staff members are highly concerned with EFS which should be provided for introduction after a full discussion how to evaluate.

Education, Medical↗
PubMed2003

[Endocrine surgery. The ninth report: the latest data on and clinical characteristics of the epidemiology of thyroid carcinoma].

Thyroid disease is comparatively prevalent, and it is important to perform careful palpation of the anterior neck when patients are first examined. In this paper, the latest data on and clinical characteristics of the epidemiology of thyroid carcinoma are described. According to Japanese cancer statistics, in 1996, the number of cases of thyroid carcinoma was 1,390 men and 5,437 women. The female to male ratio was 3.91: 1. The crude rate of thyroid carcinoma per 100,000 population was 2.3 men and 8.5 women. The age-adjusted incidence rate showed a gradual increase with age, and the peak of the age-adjusted incidence rate was over 80 years old among men, and from 70 to 80 years old among women. According to the Japanese Thyroid Cancer Registration Committee, from 1977 to 1999, papillary thyroid carcinoma accounted for more than 85% (30,256) of thyroid carcinomas among 35,312 patients. Medullary thyroid carcinoma (1.4%) and anaplastic thyroid carcinoma (1.6%) were rare. The female to male ratio of thyroid carcinoma was 6.1: 1. Registration was made in accordance with the general rules issued by the Japanese Society of Thyroid Surgery. According to the vital statistics, mortality related to thyroid carcinoma among all cancer-related deaths was 0.23% among men (411) and 0.76% among women (887) in 2000. The female to male ratio of mortality was 2.16: 1. The peak of mortality was from 70 to 80 years old among men, and from 80 to 90 years old among women. Most patients with differentiated thyroid carcinoma had a low mortality rate, but anaplastic carcinoma had a poor prognosis. Lung and bone were the main distant metastatic sites, and respiratory insufficiency was the most common specific fatal condition.

Adolescent↗
PubMed2003

Radioguided parathyroidectomy for renal hyperparathyroidism.

BACKGROUND: The usefulness of radioguided parathyroidectomy for primary hyperparathyroidism has been demonstrated in recent years, however, its applicability to renal hyperparathyroidism is uncertain. We report a case in which radioguided parathyroidectomy was used to treat renal hyperparathyroidism and was found to be helpful in preventing persistent and recurrent hyperparathyroidism. CASE REPORT: The patient was a 55-year-old Japanese woman who had received hemodialysis for 67 months. Three enlarged parathyroid glands were identified preoperatively by ultrasonography. Two hours before the operation, the patient received an intravenous injection of 600 MBq 99mTc-sestamibi and radioguided parathyroidectomy was performed. The three enlarged parathyroid glands were resected easily by the use of radioguided surgery. However, the localization of the residual parathyroid gland was uncertain. The operative field was analyzed using an intraoperative gamma probe, and the upper mediastinum was found to have higher radioactivity than the other regions. The upper mediastinum was dissected and the enlarged parathyroid gland was identified in the anterosuperior mediastinum in front of the trachea. The target parathyroid gland was then removed. The pathological diagnosis was hyperplasia of the parathyroid. No complications were observed and a follow-up examination 30 months later did not show any recurrence. CONCLUSIONS: An intraoperative gamma probe can be used to locate supernumerary and ectopic parathyroid glands. Radioguided parathyroidectomy for renal hyperparathyroidism can theoretically decrease the risk of persistent and recurrent hyperparathyroidism that is due to remaining parathyroid tissue.

Female↗
PubMed2003

Radioguided parathyroidectomy for primary hyperparathyroidism using the solid-state, multi-crystal gamma camera.

BACKGROUND: Minimally invasive radioguided parathyroidectomy (MIRP) offers several cosmetic and surgical advantages. Intraoperative 99m-Tc sestamibi scintigraphy using a solid-state, multi-crystal gamma camera was used to perform the MIRP. We report a case of primary hyperparathyroidism treated with this surgical procedure and discuss the usefulness of intraoperative scintigraphy. CASE REPORT: The patient was a 58-year-old Japanese woman was given a diagnosis of primary hyperparathyroidism. One hour before the operation, 99m-Tc sestamibi was injected intravenously and scintigraphy was performed in the operating room before the skin incision. Sestamibi imaging revealed an abnormal uptake close to the lower right lobe of the thyroid gland and MIRP was performed. After the tumor behind the right recurrent laryngeal nerve close to the lower right lobe of the thyroid gland was removed, intraoperative scintigraphy still revealed an abnormal uptake. MIRP was continued and an abnormal parathyroid gland behind the right carotid artery near the right recurrent laryngeal nerve was identified. After removing a parathyroid adenoma from this second location, intraoperative sestamibi imaging revealed no abnormal uptake. RESULTS: The operation time was 80 minutes and the amount of bleeding was 12 ml. Postoperatively, serum calcium and PTH levels were within normal range. No complications were observed. CONCLUSIONS: Intraoperative sestamibi imaging using a portable gamma camera is useful for locating abnormal parathyroid glands.

Female↗
PubMed2002

Functional mediastinal parathyroid cyst: report of a case.

We report herein a rare case of a functional mediastinal parathyroid cyst. A mediastinal tumor was detected by a chest X-ray film and subsequent computed tomography (CT) scan in a 68-year-old woman who was asymptomatic. Biochemical examination revealed that her serum calcium and intact-parathyroid hormone (i-PTH) levels were above the normal range. The findings of chest CT and magnetic resonance imaging suggested a cystic mass. The mass, which adhered tightly to its surrounding structures, was resected through a median sternotomy. The patient had an uneventful postoperative course, and her serum calcium and i-PTH levels rapidly returned to within the normal range.

Aged↗
PubMed2002

Video-assisted endoscopic thyroid and parathyroid surgery using a gasless method of anterior neck skin lifting: a review of 130 cases.

PURPOSE: Endoscopic endocrine neck surgery is desirable from a cosmetic viewpoint. We compared the effectiveness of our new technique with that of conventional surgery in a clinical study. METHODS: We performed our original endoscopic method of video-assisted neck surgery (VANS) on 130 patients: 126 with thyroid tumors and 4 with parathyroid tumors. The percentage of patients who underwent VANS among all those who underwent neck surgery and the procedure involved were analyzed. Operating time and blood loss were compared between the first 40 patients and last 39, and all factors were statistically analyzed in the most recent 20 patients who underwent the VANS method and the most recent 20 who underwent conventional surgery. RESULTS: More than 60% of benign thyroid tumors and 5.3% of malignant thyroid tumors were operated on by the VANS method. Nearly total lobectomy was the most common procedure (57.7%), followed by total lobectomy (26.1%), for benign tumors. Malignancy was defined as papillary carcinoma less than 1 cm in diameter. Total lobectomy with lymph node clearance was performed for all malignant tumors. There was less bleeding when the VANS method (P < 0.001) was used than when conventional surgery was performed, and the operating time has been reduced with experience. CONCLUSION: The VANS method is feasible, practical, and safe, and has great cosmetic benefits.

Humans↗
PubMed2002

Video-assisted neck surgery for thyroid and parathyroid diseases.

BACKGROUND: Endoscopic surgery has now become a well-established modality for the treatment of various organ diseases. In the present study, we analyzed the surgical results achieved by video-assisted neck surgery (VANS) in thyroid and parathyroid diseases. METHODS: From January 2000 to April 2002, 87 patients (eight males and 79 females) with a mean age of 49 years underwent VANS. The preoperative diagnoses of these patients included 37 benign thyroid tumors, 30 Graves' diseases, 17 parathyroid adenomas and three thyroid cancers. RESULTS: The mean operative time of VANS was 165 min for a hemithyroidectomy, 287 min for a subtotal thyroidectomy, and 157 min for a parathyroidectomy. The mean intraoperative blood loss was 60, 183 and 23 g for a hemithyroidectomy, subtotal thyroidectomy and parathyroidectomy, respectively. No conversion from VANS to conventional surgery was experienced. Three patients (3.4%) had temporary palsy of the recurrent laryngeal nerve. Otherwise, the postoperative courses were uneventful. CONCLUSIONS: VANS for thyroid and parathyroid diseases was found to be safe and effective. From a cosmetic point of view, a high degree of patient satisfaction was obtained. VANS is thus considered to be an excellent option for selected patients with thyroid and parathyroid diseases.

Adolescent↗
PubMed2002

Video-assisted minimally invasive endoscopic thyroid surgery using a gasless neck skin lifting method--153 cases of benign thyroid tumors and applicability for large tumors.

Endoscopic surgery is often considered to be 'minimally invasive surgery' in the light of recent developments. In particular, endoscopic endocrine neck surgery is desirable from a cosmetic viewpoint. Here we compared the usefulness of our original endoscopic method of video-assisted neck surgery (the VANS method) with conventional surgery when challenged with the removal of thyroid tumors measuring more than 5 cm in diameter, based on our experience with 167 cases (162 thyroid tumors, five parathyroid tumors). The percentage of patients who underwent the VANS method of the total number of patients who underwent neck surgery was determined and the operative procedures used in the different surgeries were analyzed. The operating time and blood loss for 153 benign thyroid tumors were statistically compared between the small-tumor group (n = 130, < 5 cm) and the large-tumor group (n = 23, > or = 5 cm). More than 60% of the benign and 5.3% of the malignant thyroid tumors were operated on by the VANS method. Near- or subtotal lobectomy was the most common procedure (64.1%) for benign tumors. Malignancy was defined as papillary carcinoma less than 1 cm in diameter. Total lobectomy with lymph node clearance was performed for all malignant tumors. Although the operating time and the blood loss were statistically greater in the large-tumor group than the small-tumor group, with increased experience it was possible to remove tumors of up to 7.4 cm safely. Our findings support the idea that the VANS method is feasible, practical, and safe, and has great cosmetic benefits, even for the removal of large benign tumors.

Humans↗
PubMed2002

Trial of autotransplantation of cryopreserved thyroid tissue for postoperative hypothyroidism in patients with Graves' disease.

BACKGROUND: Some patients with Graves' disease who select surgical therapy so they can discontinue antithyroid medication require lifelong levo-thyroxin (l-T4) replacement therapy because of irreversible postoperative hypothyroidism. The aim of this study was to enable the replacement of absent thyroid hormone through autotransplanted thyroid tissue that had been cryopreserved since the initial thyroid operation, and to release these patients from lifelong l-T4 administration. STUDY DESIGN: At the time of subtotal thyroidectomy for Graves' disease, the surgical specimen was partially cryopreserved at -196 degrees C until it was used for autotransplantation. After obtaining sufficient informed consent, four patients with postoperative hypothyroidism underwent autotransplantation of cryopreserved thyroid tissues. These patients required 50 to 150 microg/day of l-T4 at 1.8, 3.4, 3.5, and 2.8 years after operation. For the transplantation, 2.5 to 3.5 g of cryopreserved thyroid tissue was autotransplanted into the forearm muscle of each patient. RESULTS: In three of the patients, l-T4 administration could be discontinued and the clinical symptoms of hypothyroidism disappeared because of an improved serum thyroid-stimulating hormone level. Pathologic and immunohistochemical examinations of the thawed cryopreserved tissue demonstrated well-preserved thyroid structure and thyroglobulin-positive follicular cells and colloids, suggesting that the transplanted material was functional. In addition, 123I scintiscanning in patients 1 and 2 indicated an accumulation of radioactive iodine at the transplantation sites. One patient, who was able to discontinue l-T4 administration for 6 months, subsequently required l-T4 again because of recurrent hypothyroidism. BACKGROUND: Despite a few remaining uncertainties that must be resolved before this procedure is optimized, autotransplantation of cryopreserved thyroid tissue promises to be a useful therapeutic procedure for treating permanent postoperative hypothyroidism in patients with Graves' disease.

Adult↗
PubMed2002

Breast-conserving therapy in the management of early stage breast cancer: Our experience in 103 cases.

PURPOSE: The aim of this study is to determine whether our results in breastconserving therapy of 103 patients with earlystage breast cancer are comparable to those of other facilities or not. MATERIALS AND METHODS: From January 1990 to October 1999, 103 patients with earlystage breast cancer were treated by breastconserving surgery and whole breast irradiation. All patients were of Stages I or II, and the greatest dimensions of primary tumor were less than 3 cm. The median followup time was 47 months from the completion of postoperative radiotherapy. Local, regional and distant failure rates, and survival rate were presumed using the KaplanMeyer method. RESULTS: One patient suffered from local recurrence 30 months later. She was followed by simple mastectomy and kept from further recurrence. No regional relapse occurred. Distant metastases were seen in three patients:two patients in bones, and one patient in a bone and the liver after 19, 35, and 32 months, respectively. One patient died from disseminated cancer in 41 months. Only one patient died due to intercurrent disease. Both 5year and 10year diseasefree survival rates were 94.2%, and both 5year and 10year causespecific survival rates were 98.3%. CONCLUSION: Our results were comparable to previously reported data. In this stage although the followup time was too short to define the longterm outcome, it suggested that breast conserving therapy was acceptable and effective in the management of earlystage breast cancer.

Adult↗
PubMed2002

Morphological and histochemical characteristics of mast cells and the content of in-tissue histamine in various pathological parathyroids: do mast cells participate in hormone secretion in human parathyroids?

The possibility of the participation of mast cells in human parathyroid hormone secretion was studied with regard to the frequency, distribution, and sub-types of mast cells and the content of in-tissue histamine, a chemical mediator in mast-cell granules, in human parathyroids with various pathological conditions. The above factors were compared between those of a 'normal' parathyroid group and those of 'pathological' parathyroids associated with adenoma and hyperplasia. Specimens were scanned for the mean value of the mast cell number per field of microscopic view and for the ratio of the mast cell number in glandular parenchymal tissue to that in interstitial tissue. The activated state of the mast cells was examined through classifying the mast cells into two sub-types, mucosal mast cells and connective-tissue mast cells. The high-performance liquid chromatography (HPLC) method was used for assay of in-tissue histamine. The frequency of mast cells showed no difference between the groups, whereas the distribution of mast cells, showed a distinct difference. The occurrence rate of mast cells in glandular parenchymal tissue in the 'pathological' group presented an increase as compared with that in the 'normal' group. Furthermore, the occurrence rate of mucosal mast cells in an activated state also showed an increase. This suggests that mast cells are likely to participate in parathyroid hormone secretion. The histamine-content in the 'normal' group was significantly larger than that in the 'pathological' group, which was a different outcome from that observed in mast cells from the results of light microscopy. This may require taking into consideration the difference in the histamine content of the mast cells themselves between that of mucosal mast cells and connective-tissue mast cells.

Adult↗
PubMed2002

Immunohistochemical, biochemical and immunoelectron microscopic analysis of antigenic proteins on neuroendocrine cell tumors using monoclonal antibody HISL-19.

The monoclonal antibody HISL-19 was originally generated after immunizing BALB/c mice with human islet cells. We used this antibody to study a wide variety of neuroendocrine (NE) and non-NE tumors by immunohistochemical, immunoelectron microscopic, and biochemical (Western blotting) techniques. Of the thyroid tumors, HISL-19 specifically immunoreacted with medullary carcinoma of the thyroid (MCT); of the pancreatic tumors, it reacted with islet cell tumors such as insulinomas and a gastrinoma; of the adrenal tumors, it reacted with pheochromocytoma. HISL-19 showed particularly strong immunoreactivity to a gross granular material at the perinuclear area in the MCT and malignant pheochromocytoma but not in the benign pheochromocytoma, although the latter cells showed a faint and homogenous positive reactivity in the cytoplasm. The strongly HISL-19-positive material was found to consist of newly synthesized antigenic proteins with a molecular weight between 60 and 65 kilodaltons (kDa) by Western blotting. Immunoelectron microscopic analysis revealed that this antigenic protein was located in the secretory granules that appear markedly in malignant endocrine tumors, usually located close to the nucleus. Thus, HISL-19 is a useful and specific marker for the immunohistochemical diagnosis of NE cell tumors. The specific antigenic proteins of HISL-19 were defined in MCT and malignant pheochromocytoma. These proteins are speculated to be actively synthesized and more highly produced in the secretory granules of malignant endocrine tumors than benign ones. Thus, a preoperative immunohistochemical study using HISL-19 might be useful for predicting the grade of malignancy of endocrine malignant tumors and thus help determine an appropriate operative procedure, in addition to being a useful marker of neuroendocrine cell tumors.

Adenoma, Islet Cell↗
PubMed2002

[Acute suppurative thyroiditis in 7 year-old girl with piriform sinus fistula].

A 7 year-old girl was admitted to our hospital with high grade fever and redness, swelling and tenderness in left neck. CT scan revealed cyst formation (4.5x3 cm) in left lobe of thyroid with swelling of surrounding lymphonodes. We diagnosed her as acute suppurative thyroiditis and treated her with intravenous antibiotics infusion and incisional drainage. After the treatment, the clinical course was uneventful. Pharyngograph revealed left piriform sinus fistula.

Acute Disease↗