Biomedical subjects

Norio Mitsuhashi

Publications and source records attributed to Norio Mitsuhashi.

At least 37 records · Page 2Linked to original sources

PubMed2003

Outcome of breast-conserving therapy in the Tokyo Women's Medical University Breast Cancer Society experience.

BACKGROUND: The results of BCT in Japanese women have not been fully evaluated. The Tokyo Women's Medical University Breast Cancer Society initiated BCT protocols in 1987. Here, we present a retrospective analysis of BCT outcomes and identify prognostic factors. METHODS: The study population comprised 348 patients (353 breasts) with UICC clinical stage 0,I or II breast cancer, for whom wide excision (n= 294), quadrantectomy (n= 56) and tumorectomy (n= 3) were performed. The final pathological margin states were positive in 102 breasts (cancer cells remained within 5 mm of the surgical margin). The whole breast was irradiated to a total dose with 44 Gy/20 fractions or 46 Gy/23 fractions in the patients with negative surgical margins. The patients with positive or close margins received 48.4 Gy/22 fractions or 50 Gy/25 fractions irradiation to the whole breast. All but 2 patients received a radiation boost to the tumor bed and all tumor beds were irradiated to more than 53 Gy. Adjuvant therapy was administered in 240 cases. The median follow-up time was 4.3 years. RESULTS: The 5-year overall, cause-specific and disease-free survival rates were 95.8%, 97.3% and 92.5%, respectively. Recurrence was observed in 29 patients including 11 patients with loco-regional recurrence. Local recurrence was observed in 6 patients, 5 of whom were premenopausal. The 5-year local control and loco-regional control rates were 98.9% and 96.6%, respectively. T status (T1 to T2) was the only significant prognostic factor for disease-free survival. No severe morbidity has been observed. Cosmetic results were excellent or good in 73% of patients. CONCLUSION: Our BCT protocols provide a high rate of local control and good cosmetic outcome. Pathologic margin status was not a major prognostic factor for local recurrence. Long term follow-up is required to reach a definite conclusion on optimal BCT protocols.

Adult↗

PubMed2003

Scatter correction by two-window method standardizes cardiac I-123 MIBG uptake in various gamma camera systems.

UNLABELLED: Heart to mediastinum count ratio (H/M) has been commonly utilized as an indicator of myocardial I-123 MIBG uptake. However, normal ranges of H/M were markedly different among various gamma camera systems. The purpose of this study was to clarify whether scatter correction by two-window method standardizes H/M among various gamma camera systems. METHODS: Scatter uncorrected and corrected MIBG imaging was acquired in phantom and human studies in combination with low energy high-resolution collimator (LEHR) and medium energy collimator (MEC). For scatter correction, energy window width of 159 keV +/- 10% was applied to main window imaging and 193 keV +/- 9.5% was applied to upper window imaging for scatter correction. RESULTS: In phantom study, a significant difference was observed in uncorrected H/M among three gamma camera systems using LEHR or MEC (2.09 +/- 0.06 vs. 2.58 +/- 0.03 in GCA7200 camera, 2.00 +/- 0.07 vs. 2.42 +/- 0.06 in DS7 camera and 2.16 +/- 0.04 vs. 2.67 +/- 0.07 in Vertex plus camera). However, there was no significant difference in corrected H/M among the three gamma camera systems, either with LEHR or MEC (2.70 +/- 0.07 vs. 2.69 +/- 0.07 in GCA7200 camera, 2.66 +/- 0.08 vs. 2.61 +/- 0.05 in DS7 camera and 2.66 +/- 0.05 vs. 2.61 +/- 0.05 in Vertex plus camera). In human study, uncorrected H/M in DS7 camera with LEHC was significantly lower than that in GCA7200 camera with MEC (1.60 +/- 0.37 vs. 1.85 +/- 0.54, N = 14). In contrast, the difference was insignificant in corrected H/M (2.12 +/- 0.59 vs. 2.16 +/- 0.68). There was a very excellent correlation in corrected H/M between DS7 and GCA7200 cameras (r = 0.991, p < 0.001). CONCLUSION: This study demonstrated that scatter correction by the two-window method standardizes the H/M in MIBG scintigraphy either with LEHR or MEC. Scatter corrected H/M can be applied to measure a standardized parameter of MIBG uptake in human clinical studies using various gamma camera systems.

3-Iodobenzylguanidine↗

PubMed2003

Logical checking function increases the accuracy of data entry in the patterns of care study.

BACKGROUND: For clinical studies, the use of a databases combined with a computer is becoming popular for data capturing. Commercially available database software has a logical checking function, which can restrict the type of data and their range. The study presented here quantitatively and prospectively evaluated the effectiveness for data management with this function using the database of Patterns of Care Study (PCS) in Japan. PATIENTS AND METHODS: The first external audit was performed from September 1998 to March 1999 using the PCS database without the function, and the second from April to September 1999 with the function. We analyzed the numbers and patterns of erroneous data for these two periods obtained with and without the function. RESULTS: In the database without the function, the number of incorrect data was 2,812 out of 596,186 (0.47%), while the corresponding number with the function was significantly reduced to 161 out of 533,656 (0.03%, p < 0.0001). CONCLUSIONS: The data accuracy was improved by using the computer database more extensively than the conventional case report form. By adding the logical checking function to the PCS database, significant improvement in the accuracy of data entry was accomplished. This indicates the potential for increasing the accuracy of data capturing with the aid of a computer.

Data Collection↗

PubMed2003

Stage IVB uterine endometrial cancer successfully salvaged by chemoradiotherapy and surgery.

A case of stage IVB adenoacanthoma of the uterine corpus is described. The patient was admitted with a large amount of atypical genital bleeding. Computed tomography and magnetic resonance imaging revealed a large tumor accompanied by lymph node involvement in the left inguinal, multiple pelvic, and paraaortic regions. She was diagnosed as having stage IVB endometrial adenoacanthoma. Neoadjuvant chemotherapy with carboplatin (CBDCA) and 5-fluorouracil (5-FU) was performed, followed by radiotherapy. The tumor responded very well, but still remained in Douglas' pouch after treatment. The patient therefore underwent a simple hysterectomy, pelvic and paraaortic lymphadenectomy, and partial rectal resection. Histopathologically, viable cancer cells were observed only in the fundus of the uterus. The patient is alive with no evidence of recurrence 4 years after the initiation of chemoradiotherapy.

Adenocarcinoma↗

PubMed2003

Radical radiation therapy for prostate cancer in Japan: a Patterns of Care Study report.

BACKGROUND: The patterns of radical radiation therapy for prostate cancer are unclear in Japan. A Patterns of Care Study was performed throughout Japan to examine the patterns of radiation therapy for prostate cancer. METHODS: From 1999 to 2000, extramural audits were performed on 50 randomly selected institutions (approximately 7% of all institutions in Japan). Detailed information was collected on a total of 311 prostate cancer patients without evidence of distant metastases, who were treated by radiation therapy between 1996 and 1998. Of these 311 patients, 162 treated radically using photon beams were analyzed in this study. RESULTS: Eighty percent of the patients had high-risk diseases defined as T3 or T4 tumors, a pretreatment prostate-specific antigen level >20 ng/ml or poorly differentiated adenocarcinoma. Androgen ablation was performed in 85.8% of patients and the median duration of hormonal therapy before and after radiation therapy was 5.3 and 21.4 months, respectively. The median total dose of radiation therapy to the prostate was 65.0 Gy (range: 20-74 Gy). The 3-year overall and biochemical relapse-free survival rates were 86.7 and 86.1%, respectively. Late toxicity was mild, with only nine patients (5.6%) exhibiting grade 2 late morbidity. CONCLUSIONS: The majority of the patients who received radical radiation therapy in Japan have high-risk disease. Androgen ablation plus radiation therapy was commonly used to treat these patients and resulted in high rates of initial control with a low risk of complications.

Adenocarcinoma↗

PubMed2003

Comparable outcomes of radiation therapy without high-dose methotrexate for patients with primary central nervous system lymphoma.

BACKGROUND: The previous trials of radiotherapy conducted for primary central nervous system lymphoma (PCNSL) have not been successful. Therefore, we have investigated the clinical outcomes and the role of radiation therapy in the treatment of PCNSL. METHODS: Thirty-three consecutive patients with PCNSL treated with cranial radiotherapy (30-40 Gy whole brain plus 10-20 Gy boost) without administration of high-dose methotrexate were retrospectively analyzed. Nine patients received whole spinal irradiation (WSI) as an additional therapy. The median age of patients was 58 years (range: 28-78 years), and 70% showed a poor performance status (PS). RESULTS: The median survival time (MST) was 13 months, and the 5-year overall survival rate was 35%. The initial response and the number of tumors were significant prognostic factors, and WSI tended toward significance in a multivariate analysis. Four of five patients, who received prophylactic WSI, were 4-year survivors without a tumor relapse and none of them had tumor involvement in the vertebral canal. One patient developed radiation-induced brain necrosis, however, WSI did not seem to affect the late complications. CONCLUSIONS: We consider it important to reduce severe acute and late complications in patients qualified for receiving an aggressive therapy, and to explore the possible tolerable and curative treatment methods that can be used in order to improve the prognosis for PCNSL. Further modifications, including the application of WSI seem to be necessary in the management of PCNSL.

Adult↗

PubMed2002

Correlations between in vivo tumor weight, oxygen pressure, 31P NMR spectroscopy, hypoxic microenvironment marking by beta-D-iodinated azomycin galactopyranoside (beta-D-IAZGP), and radiation sensitivity.

PURPOSE: The purpose of this study is to evaluate the amount of hypoxic fraction in a rodent tumor by means of polarographic oxygen electrode, phosphorus-31 magnetic resonance spectroscopy (31P-MRS), and a newly synthesized hypoxic marker, beta-D-iodinated azomycin galactopyranoside (beta-D-IAZGP). We also investigated the radiosensitivity for tumors of different weights. METHODS AND MATERIALS: Murine mammary carcinoma cells, FM3A, were subcutaneously implanted into the back of 5-week-old male C3H/He mice. beta-D-IAZGP radiolabeled with 123I or with 125I was injected intravenously into tumor-bearing mice, and marker distribution was measured by nuclear medicine procedures. Radiosensitivity of the tumor was measured by the in vivo/in vitro clonogenic assay. Tumor oxygenation status was also measured directly by polarographic oxygen electrodes and indirectly estimated from 31P-MR spectra. RESULTS: Higher accumulation of 123I-beta-D-IAZGP was observed in the tumors than in normal tissues at 24 h after administration. As to biodistribution of 125I-beta-D-IAZGP, the tumor/blood ratio varied widely, but correlated significantly with tumor weight. Mean oxygen pressure (pO2) values and ratios of nucleoside triphosphate beta to inorganic phosphate (beta-ATP/Pi) and of phosphocreatine to inorganic phosphate (PCr/Pi) decreased significantly with the increase in tumor volume. As tumor volume increased, the surviving fraction of cells from tumors irradiated in vivo increased significantly. CONCLUSIONS: The increase in tumor volume was significantly correlated with a reduction in mean pO2, a decrease in the ratios of beta-ATP/Pi or PCr/Pi, an increase in uptake of beta-D-IAZGP, and an increase in radioresistance. Because the uptake of beta-D-IAZGP can be measured noninvasively by nuclear medicine techniques, it could be clinically useful for monitoring hypoxia in human tumors.

Animals↗

PubMed2002

Redevelopment of small cell lung cancer after a long disease-free period: a case report.

Although it has been reported that the risk of second malignancies increases in long-term survivors of small cell lung cancer (SCLC) and late recurrence of SCLC is sometimes experienced, it seems uncommon. We recently experienced a case of redevelopment of SCLC after a long disease-free period. The case was considered to be second primary SCLC more than 10 years after the initial treatment. The necessity for lifelong follow-up in long-term survivors of SCLC is emphasized.

Carcinoma, Small Cell↗

PubMed2002

[A case of recurrent breast cancer with chronic renal failure treated on an outpatient basis].

We report a case of recurrent breast cancer with chronic renal failure in a 58-year-old female. She could be treated on an outpatient basis under good general condition for most of her remaining life by chemoradiotherapy in combination with hemodialysis. Modification of the chemoradiotherapy procedures and collaboration of medical staff including the doctor in charge of home medical care and her family was indispensable in keeping her hospital stay as short as possible.

Ambulatory Care↗

PubMedDate not supplied

Helical CT features of arrhythmogenic right ventricular cardiomyopathy.

Arrhythmogenic right ventricular cardiomyopathy (ARVC), also known as arrhythmogenic right ventricular dysplasia, is a disorder of the heart muscle of unknown origin. It is characterized by electrical instability of the heart as a result of replacement of the right ventricular myocardium with fatty or fibrous fatty tissue. Dilatation of the right ventricle; fatty tissue in conspicuous trabeculae of the right ventricle, especially in the anterior wall, apex, and inferior (diaphragmatic) wall; and a scalloped appearance (bulging) of the right ventricular wall are characteristic findings at helical computed tomography (CT) that may be used to diagnose ARVC. Fatty tissue in the left ventricle and ventricular septum is seen relatively frequently in ARVC, and fat in the ventricular septum is another useful finding for diagnosis of ARVC with helical CT. ARVC is usually diagnosed on the basis of clinical or pathologic findings, and electron-beam CT is superior to nongated helical CT in assessment of abnormal right ventricular function. However, with knowledge of the characteristic findings, standard nongated helical CT can be helpful in diagnosing ARVC.

Arrhythmogenic Right Ventricular Dysplasia↗

PubMedDate not supplied

Comparison of primary thyroid lymphoma with anaplastic thyroid carcinoma on computed tomographic imaging.

PURPOSE: Primary non-Hodgkin's lymphoma (LY) and anaplastic carcinoma (AC) of the thyroid gland are rare malignant tumors, and the initial symptoms of these diseases are very similar. The aim of our study was to compare the characteristics of the two diseases using computed tomographic (CT) scans in order to make an accurate differential diagnosis. MATERIALS AND METHODS: Ten patients with LY and 10 with AC were analyzed. Differences in the CT findings of the two diseases were evaluated before treatment and statistically tested with either Student's t-test or the chi-square test. RESULTS: In the analysis of characteristics of CT imaging, the existence of calcification and necrosis, and heterogeneous tumor were dominant findings in AC, and there was a statistically significant difference in frequency between the two diseases (p < 0.01). Calcification detected in AC was usually multiple and/or gross (mean size: phi8.2 mm). All lymphadenopathies were delineated as having the same homogeneous attenuation as the tumors in the thyroid gland in LY, but were shown as irregular rim enhancement in AC. CONCLUSION: The CT features of the two diseases are characteristic in terms of calcification, necrosis, and tumor composition. Evaluation by means of CT imaging is useful in distinguishing between LY and AC.

Aged↗

PubMedDate not supplied

Signal transduction pathway to low-dose radiation-induced apoptosis in peripheral PNET cells.

We investigated the signal transduction pathway to low-dose radiation-induced apoptosis in vitro in the human peripheral primitive neuroectodermal tumor (pPNET) cell line with wild-type p53 established in our laboratory. Apoptosis was induced by 2Gy irradiation in an almost p53-dependent manner in this model except for a deficiency of the cleavage of caspase-9. It was detected 3 hours after irradiation by fragmentation assay. The expressions of p53, p21WAF-1 and Bax increased, in contrast to the gradually decreasing expression of Bcl-2, as observed by immunoblotting. Following this, cleavages of caspase-3 and PARP reached peak levels. There were no detectable increases in ERK expression and caspase-9 cleavage. In respect of the probability of other pathways to apoptosis, this cell line will provide a useful model both for investigating low-dose radiation-induced signal transduction pathway and for analyzing the biological characteristics of pPNET.

Adult↗

PubMedDate not supplied

Combined effect of hyperthermia at 42 degrees C and irradiation dose of 2 Gy on two rat yolk sac tumor cell lines with different radio-thermosensitivity in vitro.

BACKGROUND: Two rat yolk sac tumor cell lines, NMT-1 and NMT-1R, are of the same origin and of different sensitivity to irradiation and to heat. The aim of this study was to investigate the sensitivities of these two cell lines to combined treatments of low-dose irradiation at 2 Gy and hyperthermia at 42 degrees C. MATERIALS AND METHODS: The cell survival was assayed by soft agar clonogenic assay. After the survival curves of radiation alone and of heat alone at various temperatures were estimated, not only the effect of irradiation on heat, but the effect of heat on irradiation were evaluated with sequential treatments in both cell lines. These effects on survival curves were evaluated by the enhancement ratios at isosurvival levels of 37%, 10% and 1%, respectively. RESULTS: NMT-1 was more sensitive to radiation but more resistant to heat than NMT-1R. For 1% survival level, radiosensitivity in NMT-1 was 1.32 times that in NMT-1R, while thermal sensitivity at 42 degrees C in NMT-1R was 2.73 times that in NMT-1. For sequential treatment, thermosensitization by a radiation dose of 2 Gy in radiosensitive NMT-1 was greater than that in radioresistant NMT-1R. Following heat at 42 degrees C for 1 hour, increased radiosensitivity in NMT-1R was significant, whereas the same heat treatment produced an increase in the radiation sensitivity of NMT-1 with a reduction of the survival curve shoulder but with less slope modification. There was no difference in the surviving fraction in the time-course of a combination of heat and irradiation at various intervals within 6 hours for NMT-1 except for heating immediately after irradiation. However a significant increase in survival was observed when heat was applied more than 3 hours after 2 Gy irradiation for NMT1-R. CONCLUSION: These results from our cell lines with the same origin were useful for investigation into the interaction of irradiation with heat.

Animals↗

PubMedDate not supplied

Interaction of radiation and etoposide on two cell lines with different radiosensitivities in vitro.

PURPOSE: To investigate the differences between two rat yolk sac tumor cell lines with different radiosensitivities in etoposide sensitivity and in the sensitizing effect of etoposide in combination with irradiation. MATERIALS AND METHODS: NMT-1 is a parent radiosensitive cell line and NMT-1R is a variant radioresistant cell line. The effects were assessed by clonogenic assay. Apoptosis was evaluated by DNA fragmentation to investigate the mechanism of cell death. RESULTS: Etoposide potentiation of radiation sensitivity was manifested by elimination of the initial shoulder of the cell survival curve in radioresistant NMT-1R cells. However, there was no enhancement effect in radiosensitive NMT-1 cells. The incidence of apoptosis was elevated in NMT-1R cells treated with etoposide and radiation. CONCLUSION: Etoposide had a supra-additive effect in combination with irradiation for radioresistant NMT-1R cells due to the induction of apoptosis. However, a suppra-additive effect was not seen in radiosensitive NMT-1 cells.

Animals↗

PubMedDate not supplied

Changes in the localization of heat shock protein 72 correlated with development of thermotolerance in human esophageal cancer cell line.

BACKGROUND: The aim of this study was to investigate the relationship between the changes in the localization of heat shock proteins (Hsps) and acquisition of thermotolerance. MATERIALS AND METHODS: A human esophageal cancer cell line was used. Fractionated heat treatment with different recovery times was performed to develop thermotolerance. Changes in the localization and the expression of Hsps were examined by the immunofluorescence and immunoblot analysis. In order to inhibit Hsps induction, Hsp inhibitor, KNK437, was used. In addition, changes in susceptibility of apoptosis induction were also evaluated in thermotolerant or non-thermotolerant cells. RESULTS: Thermotolerance reached its peak at the recovery time of 120 minutes after the first heat and maximum thermotolerance was observed in consistence with the timing of appearance of cytoplasmic Hsp72. Suppression of cytoplasmic Hsp72 positivity caused by KNK437 resulted in inhibition of acquisition of thermotolerance. Caspase-3 activation and PARP cleavage, that were suppressed in thermotolerant cells, re-appeared by using KNK437, in combination with heat. CONCLUSION: The cytoplasmic localization of Hsp72 might be correlated with the development of thermotolerance.

Acclimatization↗

PubMedDate not supplied

Induction chemotherapy followed by hyperfractionated radiotherapy with concurrent chemotherapy for locally advanced head and neck cancer.

BACKGROUND: The aim of this study was to improve tumor control, the survival rate and organ preservation for locally advanced head and neck cancer by using induction chemotherapy followed by hyperfractionated radiotherapy and concurrent chemotherapy. MATERIALS AND METHODS: Thirty-five patients with stage III-IVB head and neck cancer were treated with this protocol. Induction chemotherapy consisted of cisplatin and fluorouracil and concurrent chemotherapy consisted of carboplatin and doxifluridin. Radiotherapy was administered twice a day until a dose of 72 Gy was reached. RESULTS: Twenty-two (63%) and 13 patients (37%) achieved complete responses and partial responses, respectively. In terms of non-hematological toxicities, grade 3 mucositis was observed in 49% of the patients. The overall 5-year survival was 53.5% and the progression-free survival was 40.6%. CONCLUSION: Response to induction chemotherapy was useful as a predictive factor for ultimate outcome and organ conservation. More intensive regimen or other combination chemotherapy is needed to improve treatment outcome with hyperfractionated radiotherapy.

Adult↗

PubMedDate not supplied

Selective inhibition of survival signal transduction pathways enhanced radiosensitivity in human esophageal cancer cell lines in vitro.

PURPOSE: The purpose of this study was to examine how selective inhibition of the survival signal transduction pathways affects radiosensitivity in human cancer cell lines. MATERIALS AND METHODS: Two human esophageal cancer cell lines, TE-1 (mutant p53) and TE2 (wild-type p53), were used. To inhibit the pathways selectively, 3 specific kinase inhibitors, AG1478 (an inhibitor of EGFR), PD98059 (an inhibitor of MEK) and LY294002 (an inhibitor of PI3K), were combined with radiation. RESULTS: Radiation in combination with these kinase inhibitors potentiated radiation-induced cell killing synergistically. Enhancement ratios were greater in TE-2 than those in TE-1. Radiation in combination with kinase inhibitors increased the expression of the active form of caspase-3 and the PARP cleavage only in TE-2 that has wild-type p53. CONCLUSION: Targeting the key molecules of the survival signal transduction pathway resulted in potentiation of radiation-induced cell killing. The results of this study suggest that the survival signal transduction pathways would be a molecular target in enhancing radiosensitivity.

Caspase 3↗

PubMedDate not supplied

A trial to measure local lung volume changes during respiration with CT.

PURPOSE: To evaluate changes in volume and the CT attenuation value of the pulmonary lobes and peripheral small lung tissue at full inspiration and expiration. MATERIALS AND METHODS: We designated (1000+CT insp)/(1000+CT exp)(1000+CT insp)/(1000+CT exp) as CT volume ratio, a new parameter to represent volume changes in lung tissue, and V insp/V exp as actual volume ratio: CT insp, exp: CT attenuation value of measured lung at inspiration and expiration; V insp, exp: actual lung volume measured with CT at inspiration and expiration. Ten normal healthy volunteers were investigated with 5 mm collimation CT in the supine position. RESULTS: The CT volume ratio and actual volume ratio of each lung lobe were well correlated. The CT volume ratios of small lung tissues were significantly larger in the dependent region than in the nondependent region when measured in the supine position at five levels, except at the level of the aortic arch (P<0.05). CONCLUSION: We advocated a new parameter (CT volume ratio) for representing lung tissue volume changes during respiration. The CT volume ratio might be a new noninvasive method to measure local volume changes in lung during respiration.

Adult↗