Biomedical subjects

Yasumasa Nishimura

Publications and source records attributed to Yasumasa Nishimura.

28 records · Page 2Linked to original sources

PubMed2003

Development of severe complications caused by stent placement followed by definitive radiation therapy for T4 esophageal cancer.

Esophageal stenting in previously irradiated patients is known to cause more severe complications than those in patients who were not irradiated. But there are few reports regarding the results of stent placement before radiation therapy. Three patients with stage T4 esophageal cancer with direct invasion to the trachea and/or aorta underwent radiation therapy after stent placement. Two of the three patients had received systemic chemotherapy before radiation therapy. Fifty-one to 66 Gy of radiation therapy was administrated 15 to 66 days after the stent placement. The initial response to radiation therapy was no change (NC) or progressive disease (PD). All patients died of bleeding or pneumonia caused by perforation at the site of the stents 17 to 79 days after the radiation therapy. It is strongly suggested that even in patients with locally advanced esophageal cancer with severe dysphagia, radiation therapy should precede stent placement, because the consequences of radiation therapy after stent placement are devastating, and radiation therapy alone can, potentially, resolve the symptoms.

Deglutition Disorders↗

PubMed2003

Feasibility study of the simultaneous integrated boost (SIB) method for malignant gliomas using intensity-modulated radiotherapy (IMRT).

BACKGROUND: Intensity-modulated radiotherapy (IMRT) using the simultaneous integrated boost (SIB) method was designed for treating malignant gliomas. The purpose of this study was to investigate feasibility of this treatment. METHODS: Between December 2000 and November 2002, six patients with malignant gliomas were enrolled in this study. IMRT delivered 70 Gy/28 fractions (fr)/daily 2.5 Gy to the gross tumor volume (GTV) and 56 Gy/28 fr/daily 2.0 Gy to the surrounding edema defined as the clinical target volume annulus (CTV-a). The feasibility of the treatment was assessed from both physical and clinical points of view. RESULTS: No delay due to acute radiation toxicity was observed in any of the patients. The tumor recurred locoregionally in five of the six patients. The glioblastoma (GBM) recurred in two patients during the radiotherapy and in three patients at 5.4, 4.0 and 7.0 months after the start of radiotherapy. The sites of recurrence or progression were local in the GTV in four patients and in one patient subependymal dissemination was observed. Three patients, two with GBMs and one with anaplastic astrocytoma, died of the disease at 4, 16 and 7 months after the start of radiotherapy, respectively. CONCLUSIONS: The treatment of 70 Gy/28 fr/daily 2.5 Gy to the GTV and 56 Gy/28 fr/daily 2.0 Gy to the CTV-a was feasible both physically and clinically.

Aged↗

PubMed2003

Phase I study of weekly docetaxel infusion and concurrent radiation therapy for head and neck cancer.

OBJECTIVE: This study was designed to determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of weekly docetaxel in combination with concurrent radiotherapy for treating head and neck cancer. METHODS: Twelve patients with unresectable or postoperative head and neck cancers were enrolled in a dose-escalating phase I study. Eleven of the 12 patients were postoperative patients with intermediate or high pathological risk features. Radiotherapy was delivered as a standard fractionation regimen (2 Gy/day, 5 fractions/week) to a total dose of 60-70 Gy. The starting dose of docetaxel was 10 mg/m(2) (once per week) with a subsequent dose escalation of 5 mg/m(2) in cohorts of three patients. In 2001 and 2002, 12 patients completing three dose levels were included in the study. RESULTS: The MTD of docetaxel was 20 mg/m(2). With the third dose level (20 mg/m(2)), DLT was observed in two of three patients. One experienced grade IV mucositis and another suffered from prolonged grade III mucositis-enforced treatment delay for 13 days. Hematological toxicity was minimal. Mucositis was the DLT of concurrent chemoradiotherapy using weekly docetaxel administration for head and neck cancer. CONCLUSIONS: We identified the recommended phase II dose of docetaxel as 15 mg/m(2) administered weekly with concurrent radiotherapy for head and neck cancers.

Adult↗

PubMed2003

Concurrent chemoradiotherapy with protracted infusion of 5-FU and cisplatin for postoperative recurrent or residual esophageal cancer.

BACKGROUND: We carried out the present study to investigate the feasibility and effectiveness of concurrent chemoradiotherapy (CT-RT) for postoperative recurrent esophageal cancer, which are, at present, unclear. METHODS: Between 1998 and 2002, 16 patients with postoperative loco-regional recurrence of esophageal cancer, and two patients with incompletely resected esophageal cancer were treated with concurrent CT-RT. Patients received protracted infusion of 5-FU 250-300 mg/m(2) on days 1 to 14, 1 hour infusion of cisplatin 10 mg/body on days 1 to 5 and 8 to 12, and a concurrent radiotherapy (RT) dose of 30 Gy in 15 fractions over 3 weeks. This treatment schedule was repeated twice with a gap of 1 week, for a total RT dose of 60 Gy administered over 7 weeks. RESULTS: Of the 18 patients, 13 (72%) completed the CT-RT protocol. A total RT dose of 60 Gy was administered for all except two patients, and doses of chemotherapy were reduced for five patients. Although grade 3 hematological toxicities were frequently noted, non-hematological toxicities of grades 3 and 4 were few. Of the 18 tumors, five (28%) showed complete response (CR). For patients without prior chemotherapy, the CR rate was 40% (4/10). The 2-year survival rate of 13 patients without distant metastases was 19%, with a median survival time of 9.5 months. CONCLUSION: The concurrent CT-RT protocol appears feasible and effective for patients with postoperative recurrent or residual esophageal cancer.

Adult↗

PubMed2003

Concurrent chemotherapy and radiotherapy with low-dose Cisplatin for nasopharyngeal carcinoma.

Eighty-one patients with nondisseminated nasopharyngeal carcinoma consecutively treated between January 1977 and December 1998 were analyzed to evaluate whether a concurrent adjunction of low-dose cisplatin enhances the outcome of definitive radiotherapy. Ninety-eight percent (n = 79) of the cases were ranked as stage III/IV according to the 1987 Union International Contre le Cancer staging criteria. Patients treated before 1987 and treated after 1988 were mainly managed by radiotherapy alone (historical group: n = 48) and concurrent chemoradiotherapy with relatively low-dose cisplatin (CCRT group: n = 33), respectively. The locoregional failure-free survival rate of the CCRT group was significantly better than that of the historical group (72.8% vs. 35.9% at 5 years, p = 0.0041). However, multivariate analysis identified only the total dose and the T-stage as significant independent factors for locoregional control. No difference was observed on overall, disease-specific, and distant failure-free survival between the two groups. The results of the present study suggest that concurrent adjunction of low-dose cisplatin will not improve the outcome of definitive radiotherapy for nasopharyngeal carcinoma. Full-dose concurrent chemoradiotherapy, as well as the appropriate dose escalation for better locoregional control, will be mandatory to achieve better survival.

Adult↗

PubMed2003

Additive effects of radiation and docetaxel on murine SCCVII tumors in vivo: special reference to changes in the cell cycle.

The purpose of the present study was to investigate the effects of a combination of docetaxel and irradiation in vivo with special reference to docetaxel-arrested G(2)/M-phase cells. At 24 and 48 h after intraperitoneal administration of docetaxel (90 mg/kg), tumor-bearing mice were irradiated with (60)Co gamma rays. Cell cycle distribution was analyzed by a DNA-Ki-67 double staining method using flow cytometry. An accumulation of cells in the G(2)/M phase of up to approximately 40% was observed 24 h after administration of docetaxel. Between 24 and 72 h, the percentage of cells arrested in G(2)/M phase that expressed Ki-67 decreased from 37.2% to 13.8%, in accordance with the increase in the Ki-67-negative G(2)/M-phase fraction. More than half of the cells arrested in G(2)/M phase lost their expression of Ki-67 protein between 24 and 72 h. The G(1)-phase fraction decreased from 28.4% to 8.6% at 24 h after docetaxel treatment; this remained unchanged at 72 h. These flow cytometry data suggested that docetaxel-arrested G(2)/M-phase cells did not enter the next cell cycle and were killed by docetaxel alone. Our data showed that arrest of cells in G(2)/M phase does not contribute to the synergism that has been reported for combinations of docetaxel and radiation in in vivo tumor models.

Animals↗

PubMed2003

Dynamic multidetector CT of breast tumors: diagnostic features and comparison with conventional techniques.

OBJECTIVE: We sought to analyze the features of breast tumors as revealed on dynamic multidetector CT (MDCT), to develop descriptors for these features, and to compare the performance of MDCT with the performance of other techniques used in the depiction of tumors. SUBJECTS AND METHODS. MDCT was performed in 149 women with suspected breast tumors, and 173 breast lesions were detected. These breast lesions were classified as either mass or nonmass enhancing lesions. For mass lesions, the margin, shape, and enhancement patterns were evaluated. For nonmass enhancing lesions, the distribution of enhancement and the types of time-density curve patterns were evaluated. MDCT was compared with mammography and sonography as a method of revealing breast tumors. RESULTS: Of the 173 breast lesions detected, 150 were mass lesions, 131 (87%) of which were malignant. Of the 23 nonmass enhancing lesions, 21 (91%) were malignant. The most highly predictive features for lesion malignancy were an irregular margin (100%), an irregular shape (99%), and rim enhancement (100%). Similar features were the most accurate signs of malignancy--a spiculated and irregular margin (90%). On time-density curves, the washout and plateau patterns showed high positive predictive value (93%) and sensitivity (91%) for malignancy. However, these patterns had low negative predictive value (42%) and specificity (48%). Seven breast lesions that could not be detected on mammography or sonography were identified on MDCT. MDCT more accurately revealed the margin of the tumor invasion in 11 breast tumors than did mammography or sonography. CONCLUSION: The features revealed on MDCT can help to distinguish benign lesions from carcinomas. MDCT can add to the data obtained with mammography or sonography in patients with suspected breast tumors.

Adult↗

PubMed2003

[Clinical practice guideline on radiation therapy for lung cancer].

Clinical practice guidelines for radiation therapy in the treatment of lung cancer were prepared by an expert multidisciplinary Panel. This project was supported by a Grant-in-Aid from the Ministry of Health, Labour and Welfare of Japan, with the primary objective to develop efficient practice guidelines for the treatment of lung cancer by systematic review of currently available evidence. We reviewed pertinent evidence from the published literature with a computerized search on MEDLINE, and filled in abstract forms for the most relevant. All abstract forms were reviewed by other experts in the panel. The extracted problems were as follows: the basics for radiotherapy including machines, planning equipments and quality assurance, definitive radiotherapy for medically inoperable or unresectable non-small cell lung cancer, chemoradiotherapy for non-small or small cell lung cancer, prophylactic cranial irradiation, and palliative irradiation for bone and brain metastases. Values for levels of evidence and grades of recommendation for each problem were discussed and approved by the panel. Essentially, the guidelines propose the minimum requirements for clinical practice. These guidelines, therefore, are expected to be useful for individualized treatments for lung cancer patients.

Bone Neoplasms↗

PubMed2002

Prospective trial of concurrent chemoradiotherapy with protracted infusion of 5-fluorouracil and cisplatin for T4 esophageal cancer with or without fistula.

PURPOSE: A prospective trial of concurrent chemoradiotherapy (CT-RT) with a protracted infusion of 5-fluorouracil and cisplatin was performed to evaluate the safety and efficacy of this protocol for T4 esophageal cancer (UICC 1997). METHODS AND MATERIALS: Between 1998 and 2000, 28 patients with T4 esophageal squamous cell carcinomas were treated with concurrent CT-RT. Of the 28 patients, 15 had Stage III, 5 Stage IVA, and 8 Stage IV disease. Five of the T4 tumors had evidence of fistula before treatment. Patients received a protracted infusion of 5-fluorouracil 300 mg/m(2)/24 h on Days 1-14, a 1-h infusion of cisplatin 10 mg/body on Days 1-5 and 8-12, and concurrent radiation at a dose of 30 Gy in 15 fractions during 3 weeks. This schedule was repeated twice, with a 1-week split, for a total RT dose of 60 Gy during 7 weeks for 25 patients. For the remaining 3 patients, 30 Gy of preoperative CT-RT was administered. RESULTS: Of the 25 patients who were treated with the full dose of CT-RT, 14 (56%) completed the two courses of the CT-RT protocol, and 8 patients (32%) received the full dose of RT but a reduced dose of chemotherapy. Eight (32%) of the 25 tumors showed complete regression. Although Grade 3 hematologic toxicities were frequently noted, Grade 4 or more hematologic toxicities were few. Of the 5 T4 fistulous tumors, 2 demonstrated the disappearance of the fistula after CT-RT. However, the worsening or development of an esophageal fistula was noted in 5 patients. The 2-year survival rate for patients with Stage III was 27%, and the median survival time for those with Stage III and Stage IVA+IV was 12 and 5 months, respectively. CONCLUSION: Despite its significant toxicity for esophageal fistula, this concurrent CT-RT protocol of protracted 5-fluorouracil infusion and cisplatin appears feasible and effective for T4 esophageal cancer with or without fistulas.

Aged↗

PubMedDate not supplied

Results of radiation therapy for superficial esophageal cancer using the standard radiotherapy method recommended by the Japanese Society of Therapeutic Radiology and Oncology (JASTRO) Study Group.

BACKGROUND: Superficial esophageal cancer (SEC) is defined as esophageal cancer limited to the submucosal layers, including mucosal cancer and submucosal cancer, and is squamous cell carcinoma in most patients. In 2000, the Japanese Society of Therapeutic Radiology and Oncology (JASTRO) Study Group for SEC published a consensus guideline of standard radiotherapy methods. In this study, the interim treatment outcomes of SEC patients, who had received radiation therapy following the standard radiotherapy methods, were investigated. PATIENTS AND METHODS: From 2000 to 2003, a total of 141 SEC patients were treated in 24 institutions in Japan. RESULTS: The 1-, 2- and 3-year survival rates were 95%, 90% and 90%, respectively, for patients with mucosal cancer and 90%, 81% and 70%, respectively, for patients with submucosal cancer. The overall survival was better in patients who had undergone chemotherapy than in patients who had received radiation therapy alone, though the difference was not statistically significant. The clinical target volume (CTV) did not influence overall survival and intracavitary irradiation did not influence the local control rate in either patients with mucosal or submucosal cancer. Radiation-induced esophageal ulcer was not observed in this series. CONCLUSION: The standard radiotherapy methods are safe and effective for treating SEC. However, the usefulness of chemotherapy and intracavitary irradiation and the optimal setting of the CTV should be clarified by future randomized trials.

Aged↗