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R Nishimura

Publications and source records attributed to R Nishimura.

357 records · Page 20Linked to original sources

Effect of simple omentoplasty and omentopexy in the prevention of complications after pelvic lymphadenectomy.

This multicenter collaborative study prospectively evaluated the effect of omentoplasty and omentopexy on the prevention of complications after pelvic lymphadenectomy. Sixty-four consecutive patients (42 cervical and 22 endometrial cancer) were enrolled and examined periodically for 12 months. All patients underwent simple, semiradical, or Okabayashi's radical hysterectomy and complete pelvic lymphadenectomy. The infracolic omentum was longitudinally divided in half and omentoplasty was performed so that bilateral omental flaps would reach the pelvic floor. The omental flaps were inserted into the retroperitoneal space and the edges of the flaps were sutured to the psoas muscle. The omental flap was then covered by the peritoneum. Incidence of lymphocele, lymphedema, and severe complications associated with lymphocele, such as infection or urinary stenosis, was evaluated at intervals for at least one year after surgery. Among the 64 patients, 12 patients received pelvic radiation because of occult lymph node metastasis. Planned omentoplasty was not possible in one patient because her omentum was too small; therefore, only unilateral omentopexy was performed. Asymptomatic lymphoceles only were detected by ultrasonogram in 12 patients (18.8%). Three patients (4.7%) had a symptomatic but pressure-only lymphocele. Hydronephrosis and bladder compression probably due to lymphocele were observed in one patient, respectively (3.1%), but resolved within 6 months. Lymphedema was observed in seven patients (10.9%) and persisted for more than 6 months in two patients (3.1%). We conclude that this simple technique of omentoplasty and omentopexy appeared to be effective in reducing the incidence of complications after pelvic lymphadenectomy.

Adult↗

Respiratory reflexes in response to upper-airway administration of sevoflurane and isoflurane in anesthetized, spontaneously breathing dogs.

OBJECTIVE: To evaluate the respiratory effects occurring during administration of sevoflurane or isoflurane to the upper airway in dogs. STUDY DESIGN: A prospective, randomized study. ANIMALS: Twelve healthy adult beagles (6 males, 6 females). METHODS: At least 2 weeks after undergoing permanent tracheostomy, dogs were premedicated with acepromazine-buprenorphine, and anesthesia was induced with thiopental and maintained with alpha-chloralose. The upper airway was functionally isolated so that the inhalant could be administered to the upper airway while dogs were breathing 100% O2 via the tracheostomy. Respiratory reflexes in response to the administration of sevoflurane or isoflurane at concentrations of 1.2, 1.8, and 2.4 times the minimal alveolar concentration (MAC) (administered in 100% O2 at a flow rate of 5 L/min) were recorded. Reflexes in response to administration of each anesthetic were also recorded following upper-airway administration of lidocaine. RESULTS: Respiratory reflexes elicited by upper-airway administration of each anesthetic were characterized by a dose-dependent increase in expiration time, with a resultant decrease in respiratory minute ventilation and increase in end-tidal PCO2. The magnitude of these responses was greater with isoflurane than with sevoflurane at 1.8 and 2.4 MAC. These reflexes were abolished after lidocaine nebulization into the upper airway. CONCLUSION: Isoflurane induces greater reflex inhibition of breathing than does sevoflurane when the anesthetic is inhaled into the upper airway at concentrations used for mask induction.

Anesthetics, Inhalation↗

Thyroid clear cell adenoma with marked dilatation of membranous structures: electron-microscopic study.

The electron-microscopic features of a thyroid follicular adenoma with clear cell change is described. The tumor was 7 mm in size and located in the upper portion of the left lobe of the thyroid of a 29-year-old Japanese female. Its cut surface was pale brown in color and well demarcated. The lesion consisted of solid nests with pinpoint lumina. The cytoplasm of the tumor cells was completely clear, but slightly vesicular without oncocytic change. Electron-microscopic examination revealed that the cytoplasm of the tumor cells was filled with numerous empty vacuoles. The vacuoles consisted of dilated membranous structures, indicating that they had been formed from rough endoplasmic reticulum and Golgi apparatus. There was no accumulation of glycogen, mucin, or lipid. The dilated membranous structures in the cytoplasm may be related to the increased thyroglobulin synthesis by the tumor.

Adenoma↗

A case control study on risk factors involved in inflammatory breast recurrence after breast-conserving surgery.

Recurrence that poses the biggest problem after breast-conserving surgery is local recurrence. Particularly, in the case of inflammatory breast recurrence which is rare but has a specific pathologic nature, it is important to elucidate the pathology and risk factors and to consider appropriate countermeasures. In the present study, we classified 133 cases of recurrence following breast-conserving surgery, collected from 18 key hospitals/institutes in Japan. Recurrence types were divided into three groups, namely, inflammatory breast recurrence, noninflammatory breast recurrence and distant metastasis only, and the risk factors involved in recurrence were investigated by the case control study allotting 2 controls to each case. The study population consisted of 9 cases of the inflammatory type, 64 cases of the noninflammatory type and 60 cases of distant metastasis. The significant risk factor for inflammatory breast recurrence was positive lymph node metastasis, which was significantly more frequent in lymphatic invasion-positive cases unlike in the distant metastasis group. The positive surgical margin and nonradiation therapy which have been shown to be significant risk factors for noninflammatory breast recurrence were entirely unrelated with inflammatory breast recurrence. In addition, the inflammatory-type recurrence time was as short as about 12 months irrespective of whether radiation therapy was performed or not. The inflammatory type was accompanied with local wide extension (cancerous embolus of the dermal lymphatic vessels), and distant metastasis (lymphangitis carcinomatosa) at the time of recurrence, and further surgery was impossible in most cases, with a significantly poorer prognosis than the other recurrence types. These findings suggest that this recurrence corresponds to the so-called 'occult' case of primary inflammatory breast carcinoma. We think it important to predict this recurrence by close pathological examination, particularly in patients with lymph node metastasis, and to consider appropriate measures.

Adenocarcinoma↗

Effects of concomitant use of doxifluridine, radiotherapy and immunotherapy in patients with advanced cervical cancer.

Clinical effects of doxifluridine (group A, 600 mg/body/day; group B, 800 mg/body/day) combined with radiotherapy and immunotherapy were evaluated in patients with advanced cancer of the uterine cervix. Response rates were 84.2% (16/19 patients) in group A and 100% (18/18 patients) in group B, respectively (p=0.230). There was no significant difference in adverse reaction incidence between the methods but significantly higher grade adverse reaction were observed in group B than in group A (p=0.048). Time to progression (TTP) was longer in group B than in group A (p=0.081). The optimal 5'-DFUR dose was 800 mg/body (group B), by which higher grade adverse reactions were fully controlled and TTP was prolonged.

Adult↗

Thymidylate synthase levels as a therapeutic and prognostic predictor in breast cancer.

5-Fluorouracil (5-FU) is a commonly used adjuvant therapeutic drug in treating breast cancer. 5-FU is metabolically converted to 5-fluorouracil-2'-deoxyuridine-5'-monophosphate-(FdUMP) which is believed to inhibit DNA synthesis in neoplastic cells by forming a tightly bound ternary complex with thymidylate synthase (TS). In the present study, we examined the possible relationship between TS levels and clinico-pathologic and prognostic features in breast disease. Mean TS levels of 2.9 pmol/g, 6.1 pmol/g, and 23.1 pmol/g were obtained in cases of benign breast disease (3 cases), primary breast cancer (115 cases), and recurrent tumors (4 cases), respectively. In breast cancer, mean TS levels significantly correlated with S-phase fraction (SPF), DNA polymerase a and lymphatic invasion. Thus, TS levels in breast cancer significantly reflected cell proliferation and malignancy. Regarding the survival rate, patients with TS values above 10 pmol/g showed an unfavorable prognosis. The effectiveness of adjuvant 5-FU derivatives chemotherapy was reflected in a higher disease-free survival rate in node (+) cases showing TS levels between 5 and 10 pmol/g (p < 0.1), but not in node (-) cases. In conclusion, TS levels in neoplastic tissues of the breast were highest in recurrent tumors, followed by those in primary cancer, benign breast disease and in breast cancer which reflected proliferative activity. Breast cancers with extremely high TS levels were accompanied by an unfavorable prognosis; however, those with moderately high TS levels tended to respond to adjuvant chemotherapy with 5-FU derivatives.

Adult↗

Differential diagnosis of small round cervical lymph nodes: comparison of power Doppler US with contrast-enhanced CT and pathologic results.

PURPOSE: The purpose of this study was to differentiate reactive small round lymph nodes (SRLNs) from metastases by power Doppler ultrasonography (PD-US) and contrast-enhanced CT (CE-CT). MATERIALS AND METHODS: Both PD-US and CE-CT were performed in 99 cervical lymph nodes (LNs) with a maximum diameter of 1.5 cm or smaller and maximum longitudinal/transverse ratio of 1.5 or smaller in 76 patients with head and neck cancer. At pathologic examinations, 45 were reactive and 54 were metastatic LNs. The vascular patterns on PD-US were classified as hilar, avascular, peripheral, and miscellaneous vascular patterns. The enhancement patterns on CE-CT were classified as homogeneous, heterogeneous, and ring enhancement. RESULTS: On PD-US, the hilar pattern was more frequently associated with benignancy (91%) and the peripheral, miscellaneous vascular pattern with malignancy (91%). The avascular pattern included both benign (58%) and malignant (42%) LNs. On PD-US, accuracy was 85%. On CE-CT, ring enhancement showed metastasis (100%), and these LNs showed avascular or peripheral patterns on PD-US. On CE-CT, accuracy was 77%. When information on CE-CT results was added to PD-US results, the accuracy rate increased significantly, to 94% (p=0.01). CONCLUSION: Vascular patterns evaluated with PD-US and enhancement patterns on CE-CT can characterize SRLNs. For an avascular pattern on PD-US, information on CE-CT results can significantly increase the accuracy of characterization.

Adult↗

MR imaging of late radiation brain injury.

One hundred and four patients treated with radiotherapy for intracranial tumors and their related conditions were reviewed to evaluate the usefulness of magnetic resonance (MR) imaging in demonstrating increased signal intensity areas on T2-weighted images that were considered to be late adverse effects of irradiation of the brain. High signal intensity areas of the white matter were divided into five patterns according to their size and extension. Severity was found to increase with age and irradiation doses of more than 50 Gy. In patients with irradiation doses of more than 60 Gy, the severity of increased with shorter interval after radiotherapy than in those given low irradiation doses. Clinical findings such as mental deterioration, motor abnormality, and visual defect were observed in 12 patients. These findings were closely correlated with the severity of the MR pattern. In most patients, high signal intensity areas were stable or progressive during the course of follow-up. However, these areas were regressive in three patients. Imaging with Gd-DTPA was performed in 36 patients, six of whom showed enhancement. Pathological findings on enhancement included astrocyte proliferation and coalescing vacuoles in neural tissue. MR imaging is an excellent method with which to monitor the adverse effects of radiotherapy of the brain.

Adult↗

MR Gd-DTPA enhancement of radiation brain injury.

MR examinations of 104 patients who had undergone radiotherapy to the brain were reviewed. Thirty-six patients received Gd-DTPA enhanced study during the course of MR evaluation and six of the patients showed enhancing radiation necrosis. Histopathological confirmations were obtained in three patients. Gd-DTPA enhancing radiation lesions were multiple and patchy in three patients, multiple and patchy with cyst formation in two and ring shaped in one. In terms of their distribution, enhancing lesions in four patients were seen only in the white matter within the irradiated field and these patients had undergone radiotherapy within five years. The interval after radiotherapy was more than eight years in two patients and their enhanced lesions were observed in both the white and gray matter. Histopathological findings of Gd-DTPA enhancing radiation necrosis were gliosis and coalescing vacuoles of the neural tissue. None of these enhanced radiation lesions showed significant mass effects. Patterns of the enhancement were not specific. It was considered to be difficult to differentiate tumor recurrence from radiation necrosis with conventional Gd-DTPA enhanced MR examinations. In one patient, delayed MR images after Gd-DTPA administration showed increases in the size and number of radiation enhanced lesions. Dynamic and delayed MR study might add more information to conventional imaging after Gd-DTPA. Further studies are necessary to differentiate radiation lesions from tumor recurrences.

Adult↗

Carbon-13 chemical shift imaging of [1-13C] glucose under metabolism in the rat head in vivo.

Carbon-13 chemical shift images (metabolic maps) of [1-13C] glucose in the heads of rats were obtained and compared with proton images of the same rats in terms of signal allocation. Wistar rats were kept awake or anesthetized. [1-13C] glucose was injected intravenously in a dose of 1 g per kg of body weight. The head of the Wistar rat was placed on or into circular coils. Carbon-13 images were obtained using a 7.05 Tesla system. A simple spin echo sequence was used with a chemical shift selective (CHESS) pulse. The frequency band width was set to cover the spectral breadth of the carbon-13 signal of [1-13C] glucose. The slice thickness of the image was 4 mm or 6 mm, and the field of view (FOV) was 60 mm x 60 mm, with a matrix size of 64 x 64. The total acquisition time was 36 minutes. Strong signals were observed from the scalp muscles and tissues outside the brain, but signal strength from the brain itself was minimal. This was presumably due to the metabolism of [1-13C] glucose in the brain. Little difference was recognized between [1-13C] glucose images of the heads of rats with and without anesthesia. Chemical shift imaging of carbon-13 could be useful methods for the in vivo study of physiochemical structures and metabolic pathways of living organs.

Animals↗

Radiological findings of vanishing tumor of the stomach.

Four lesions in three patients with so-called vanishing tumor of the stomach are described. Two patients had one lesion each and the third patient two lesions. The lesions were localized in the gastric cardia, angle, and antrum. Radiological findings of these tumors showed a round tumor with smooth surface and regular margins. The edges of the tumors were gently sloping, while the mucosa surrounding the tumor was edematous. The time interval until these tumors disappeared was five days, 20 months, 12 months and seven months, respectively. When the soft appearance of a gastric tumor is suspected in UGI examination, the patient should be re-examined after a month or more, to avoid unnecessary surgery.

Adult↗

The role of radiation therapy in adult T-cell leukemia.

Five patients with adult T-cell leukemia (ATL) were treated by irradiation. Of the five patients, four were irradiated only locally to enlarged lymph nodes or cutaneous lesions as a palliative therapy. The other patient was given a single dose of 10 Gy to the total body as a definitive treatment, followed by autologous bone marrow transplantation. All five patients were treated by combined chemotherapy before irradiation. Complete reduction of lymph node enlargement and cutaneous lesions was achieved with a dose of 20 to 30 Gy. Four patients died within three months after radiotherapy, but there was no recurrence in the radiation field while new lesions developed. One patient in whom cutaneous lesions developed again after nine months of remission was alive at 10 months after irradiation. These patients responded poorly to chemotherapy. Local lesions produced by ATL were sensitive to irradiation and could be controlled by moderate irradiation doses without severe side effects. Radiotherapy did not prolong survivals, but it should be considered as a palliative method in multimodal treatment for ATL.

Adult↗

MR imaging of lingual carcinoma: comparison with surgical staging.

The purpose of this study was to determine the usefulness of magnetic resonance (MR) imaging for the preoperative staging of 18 patients with lingual carcinomas. Tumor stage as determined by MR imaging was compared with pathological stage. Conspicuity of tumors was compared among dynamic MR, T2-weighted, and postcontrast T1-weighted images. The tumor stage was evaluated correctly with MR imaging in 15/18 patients (83.3%). One patient was overstaged and two understaged due to incorrect diagnosis of size. In all T4 cases, tumor extension was diagnosed correctly. Dynamic MR and T2-weighted images were superior to postcontrast T1-weighted images in delineating and showing the extension of carcinomas. However, dynamic MR imaging showed no significant superiority to T2-weighted imaging. We conclude that MR imaging is of great value in the staging of lingual carcinoma. Dynamic study should be performed only when the lesion is undetectable or equivocal on T2-weighted imaging.

Adult↗

Azelastine: its clinical application for radiation dermatitis.

A retrospective analysis was performed to investigate the radioprotective effects of azelastine against radiation dermatitis for patients with head and neck cancers. The effects of azelastine were studied in 19 patients with laryngeal cancers treated by irradiation. As controls, 29 patients with laryngeal cancers treated by irradiation without the administration of azelastine were studied. All patients were irradiated using 3 MV linac X-rays. Azelastine was administered orally twice a day. Moist desquamation was observed in four of 29 control patients whereas no such moist desquamation developed after the administration of azelastine. Two cases of moist desquamation that developed before the administration of azelastine regressed during irradiation in patients placed on azelastine. Radiotherapy was completed without interruption in all patients treated with azelastine. No severe side effects were observed. Azelastine, administered orally, was a safe drug and has the potential of improving skin tolerance in irradiation therapy.

Anti-Inflammatory Agents, Non-Steroidal↗