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Akihiro Hayashi

Publications and source records attributed to Akihiro Hayashi.

At least 19 recordsLinked to original sources
PubMed2005

Repeat pulmonary resection for isolated recurrent lung metastases yields results comparable to those after first pulmonary resection in colorectal cancer.

Pulmonary resection for colorectal metastases is well accepted. However, the main cause of death after pulmonary resection is recurrence in the lung. The aim of this study was to clarify whether a repeat pulmonary resection was warranted in patients with recurrent lung metastases. The records of 76 patients undergoing initial pulmonary resection, including 14 patients undergoing a repeat operation for lung metastases, were reviewed for survival, operative morbidity, and mortality. Overall, pulmonary resection was performed 96 times in this group of patients. The operative mortality was 0%, morbidity involved only one case of major postoperative hemorrhage associated with the first operation. The cumulative 5-year survival rate for the 76 patients was 32%. After the second pulmonary operation, recurrence was identified in 79% (11 of 14) of the patients. In 10 patients with isolated lung recurrence after a first pulmonary resection, who showed no extrapulmonary disease before or at the time of first thoracotomy, the 3-year, and 5-year-survival rate after the second pulmonary resection was 67%, and 33%, respectively, comparing favorably with the survival rate in those who underwent primary pulmonary resection. In contrast, all 4 patients with extrapulmonary disease before or at the time of thoracotomy had poor prognosis. Repeat pulmonary operation for isolated recurrent colorectal metastases to the lung yielded results comparable to those after the first pulmonary resection in terms of operative mortality and survival in the absence of hilar/mediastinal lymph node or extrathoracic involvement.

Adult↗
PubMed2004

Preoperative spirometry versus expired gas analysis during exercise testing as predictors of cardiopulmonary complications after lung resection.

PURPOSE: As cardiopulmonary load increases with the amount of lung resected, to perform surgery safely it is important to be able to predict cardiopulmonary insufficiency. However, lung function testing with spirometry and blood gas analysis does not accurately measure cardiopulmonary reserve. We conducted this study to evaluate expired gas analysis during exercise testing for predicting postoperative complications after lung resection. METHODS: Expired gas analysis during exercise and spirometry were done 1 week preoperatively in 211 patients who underwent pulmonary resection for lung cancer. Patients were divided postoperatively according to whether cardiopulmonary complications were absent (group A) or present (group B). RESULTS: In group B there were more men than women (P < 0.01), and the mean age was greater (P < 0.05). There was no difference in disease stage, but more patients underwent pneumonectomy in group B than in group A ( P < 0.005). The results of expired gas analysis during exercise testing and of spirometry showed that maximum oxygen uptake/m(2) (P < 0.0005), anaerobic threshold/m(2) (P < 0.01), vital capacity (VC)/m(2) (P < 0.005), %VC (P < 0.0001), forced expiratory volume in 1 s (FEV(1.0))/m(2) (P < 0.0001), and FEV(1.0%) (P < 0.05) were lower in group B than in group A. CONCLUSIONS: The combination of expired gas analysis during exercise and conventional pulmonary function tests identified patients at risk for postoperative cardiopulmonary complications following pulmonary resection.

Aged↗
PubMed2004

Amyloid tumor in the anterior mediastinum: report of a case.

A 33-year-old woman being treated for rheumatoid arthritis was referred to our hospital for investigation of a mediastinal mass. A chest computed tomography scan showed an anterior mediastinal mass, 8.5 x 7.0 cm in size, with a cystic lesion and calcification. These findings were suggestive of either a noninvasive thymoma or a mature teratoma. Therefore, we performed tumor resection and thymectomy. Histologically, the tumor consisted of diffuse deposits of massive eosinophilic amorphous material. The tumor was stained red-orange by Congo red, and the staining disappeared following potassium permanganate digestion. Based on these findings, a diagnosis of reactive amyloidosis of the amyloid A-protein-derived type was made. Amyloidosis in the mediastinum has rarely been described.

Adult↗
PubMed2004

Incidental partial anomalous pulmonary venous connection in left lung cancer.

We present the case of a 79-year-old woman with partial anomalous pulmonary venous connection (PAPVC), discovered incidentally during upper left division segmentectomy for primary lung cancer. The left superior pulmonary vein originated from the hilum of the upper left lobe and flowed into the left brachiocephalic vein. The left inferior pulmonary vein was connected normally, and neither atrial septal defect nor other anomalous condition was present. Upper left lobectomy with ligation of the anomalous connected vein was performed, as the lingual segment was anatomically difficult to retain. Although this type of PAPVC is extremely rare, it is advisable to exercise caution when performing lung resection with the potential for PAPVC in mind.

Aged↗
PubMed2004

Fixation of silicone stents in the subglottic trachea: preventing stent migration using a fixation apparatus.

Silicone stents are widely used to treat benign or malignant airway stenosis. However, since straight silicone stents placed into the subglottic trachea to treat stenosis display a high risk of migration, novel approaches are required. The present report outlines our method of external fixation for silicone stents in the subglottic trachea. This technique utilizes a fixation apparatus, is readily performed, and may help to overcome the hesitation seen in placing silicone stents for subglottic tracheal stenosis.

Bronchoscopy↗
PubMed2003

Small peripheral pulmonary carcinomas evaluated with dynamic MR imaging: correlation with tumor vascularity and prognosis.

PURPOSE: To correlate the findings at contrast material-enhanced dynamic magnetic resonance (MR) imaging of small peripheral pulmonary carcinomas with tumor vascularity and prognosis. MATERIALS AND METHODS: Ninety-four patients with small peripheral pulmonary carcinomas who underwent surgical resection were examined retrospectively. Pathologic specimens were stained with hematoxylin-eosin and elastin-van Gieson. CD34 and vascular endothelial growth factor (VEGF) were assessed immunohistochemically. Delineated CD34-positive cells were counted as microvessels. Dynamic MR imaging was performed prior to and at 1, 2, 3, 4, 5, 6, and 8 minutes after injection of a bolus of gadopentetate dimeglumine. The two observers reviewed all images, and two pathologists performed all histologic analyses; a decision was determined with consensus. The maximum enhancement ratio (MER), the time lapse between the completion of the injection and the point of maximum signal intensity (Tmax), the washout ratio, and the slope value of the time-signal intensity curve were correlated with the microvessel density. VEGF-positive and VEGF-negative tumors were compared. All statistical analyses were performed by using nonparametric methods. RESULTS: The MER and the slope value were positively correlated, and the Tmax was negatively correlated (Spearman rank test, P <.0001, all comparisons) with the microvessel counts. The distribution of elastic and collagen fibers correlated with the washout ratio (Kruskal-Wallis test, P <.001). There was a statistically significant difference between the slope value of VEGF-positive tumors and that of VEGF-negative tumors (Mann-Whitney U test, P <.0001). Patients with VEGF-positive tumors had a significantly shorter overall survival than did those with VEGF-negative tumors (log-rank test, P <.0001). CONCLUSION: Dynamic MR imaging findings correlate with tumor vascularity and may be helpful in the prediction of prognosis.

Adenocarcinoma↗
PubMed2003

[Application of one step RT-PCR assay for detection of flavivirus RNA in mosquitoes].

The conditions of one step RT-PCR method for detection of virus RNA in field-collected mosquitoes, and preservation period of infected mosquitoes for one step RT-PCR were examined. We compared several virus RNA extraction methods with artificially contaminated mosquito pools with dengue virus (DV), Japanese encephalitis virus (JEV), and yellow fever virus (YFV) with a known amount of plaque forming unit (PFU) to establish the condition of one step RT-PCR. In this study, most effective RNA extraction method was ISOGEN-LS extraction combined with supernatant of centrifuged mosquito homogenates. Detection limit of one step RT-PCR using flavivirus universal primer in ten mosquitoes/tube (pool) was 10 PFU of DV, JEV and YFV, 1 PFU of each viruses using species-specific primer respectively, in one hundred mosquitoes/tube, 100 PFU/tube using universal primer pairs, 10 PFU/tube using species-specific primer pairs respectively. Dengue virus infected single mosquito was mixed with 99 un-infected mosquitoes, and tested by one step RT-PCR. We could detect single infected mosquito in pools containing 99 un-infected mosquitoes. Aedes aegypti and Aedes albopictus were inoculated intrathoracically with a mouse-adapted strain of dengue-1 virus and were kept up to 30 days at different temperature. Then examined by one step RT-PCR to determine the appropriate mosquito handling method and the condition of transportation. Positive result was obtained up to 30 days after the mosquito died naturally. These results suggested that we could detect flavivirus RNA tested not only from live mosquitoes but also dead mosquitoes as well, and could apply one step RT-PCR as a rapid, specific, and highly sensitive tool for flavivirus surveillance.

Animals↗
PubMed2003

Resection of synchronous lung and Vater's papilla cancer.

We present a case of a 78-year-old man with a synchronous double cancer of the lung and Vater's papilla. A pancreaticoduodenectomy was performed for Vater's papilla cancer and a partial lung resection for lung cancer. The pathological diagnosis of the tumors was a well differentiated tubular adenocarcinoma and well differentiated bronchioloalveolar carcinoma, respectively. Although most cases of synchronous double cancers involve lung and gastric cancers, a combination of lung and Vater's papilla is extremely rare. This patient is still alive with no recurrence for 5 years after the last operation.

Adenocarcinoma↗
PubMed2003

Rapid-growth lung cancer associated with a pulmonary giant bulla: a case report.

A giant bulla of the lung is suggested as a risk factor for lung cancer. Here we report a case with lung cancer in a giant bulla, which showed rapid progression. A 57-year-old man, who had a history of heavy smoking, was admitted to our hospital due to hemoptysis. A chest X-ray revealed a giant bulla with a ground glass shadow and a high fluid level in the right upper lung. Sputum cytology was negative for malignant cells. A chest X-ray a month later showed increases of the size of the radio-opaque shadow and of the air-fluid retention, suggesting pulmonary hemorrhage from the giant bulla. Limited resection or lobectomy was indicated, but pneumonectomy was performed due to the severe air-leak. Macroscopically, a multiple nodular tumor arose from the bulla wall, which might be related to blood flow and necrotic tissue. The postoperative pathological diagnosis was papillary adenocarcinoma. Unfortunately, the patient developed a recurrence of carcinoma in the pleuroperitoneal cavity and died at 2.5 months after the operation. Based on this report and review of other cases in the literature, we should keep in mind the rapid progression of lung cancer in association with an emphysematous bulla.

Adenocarcinoma, Papillary↗
PubMed2002

Outcome for malignant tracheobronchial stenoses in esophageal cancer.

OBJECTIVE: Optimal tracheobronchial stenosis treatment in esophageal cancer remains a clinical challenge. METHODS: Subjects were 26 patients with tracheobronchial stenosis due to esophageal cancer treated by modalities such as expandable metallic stent emplacement, laser therapy, radiotherapy, and/or chemotherapy. We assessed patient outcome and modality efficacy, and determined prognostic factors for survival using multivariate analysis. RESULTS: Of the 26, 16 (61%) had improved respiration after treatment. Average posttreatment survival was 140 days (10-1550 days). Multivariate analysis indicated that a Karnofsky performance score of > or = 70% was the most significant prognostic factor, with chemotherapy and laser therapy also significant factors. CONCLUSIONS: Although individual modalities were effective in ameliorating respiratory symptoms, patients with good performance status survived the longest. After a tracheobronchial stenosis diagnosis in esophageal cancer patients, chemotherapy and laser therapy are recommended if the patient is in good general condition.

Aged↗
PubMed2002

Vasoactive peptides in a pulmonary embolism model.

PURPOSE: To investigate changes in atrial natriuretic peptide (ANP) and angiotensin II (AT-II) levels in a canine model of pulmonary embolism (PE), created by embolizing the left posterior pulmonary artery with gelatin powder. METHODS: Pulmonary arterial pressure (PAP) was measured before, immediately after, and 1 day after pulmonary artery embolization. Plasma ANP and AT-II levels were measured by radioimmunoassay (RIA) before and 1, 3, 7, 14, 21, and 28 days after embolization. ANP and AT-II levels were also measured by RIA in both embolized and nonembolized lung tissue 28 days after embolization. RESULTS: No changes in plasma ANP or AT-II were seen within 28 days after embolization. Although the ANP level in the nonembolized lung tissue was significantly increased, the level in the embolized lung tissue was significantly decreased compared with that of sham-operated control lung tissue. The AT-II level in the nonembolized lung tissue was significantly decreased compared with that of the control lung tissue, but the level in the embolized lung tissue did not change. CONCLUSION: Both ANP and AT-II in the nonembolized lung tissue reacted to compensate for vasoconstriction caused by the PE in this model.

Angiotensin II↗
PubMed2002

Natriuretic peptides after pulmonary resection.

BACKGROUND: Little is known about alterations in the levels and influence of natriuretic peptide (NP) on cardiopulmonary function after pulmonary resection for lung cancer. This study was designed to investigate the patterns and activity of NP after pulmonary resection. METHODS: We investigated changes in plasma A-type (atrial) NP and B-type (brain) NP (BNP) using radioimmunoassay, in lung cancer patients before and after lobectomy (n = 15) or pneumonectomy (n = 10). Patient characteristics, respiratory function, operative time, blood loss, intraoperative fluid administration, and intraoperative urine output in both groups were also compared. Pulmonary hemodynamic variables were monitored continuously. RESULTS: Plasma concentrations of A-type NP and BNP did not differ between the two groups preoperatively. However, the group undergoing pneumonectomy exhibited higher concentrations of A-type NP and BNP than the group undergoing lobectomy on postoperative days 3 and 7. Alterations in A-type NP and BNP after pulmonary resection therefore differed according to the volume of lung tissue resected. Both mean pulmonary artery pressure and total pulmonary vascular resistance increased significantly in the pneumonectomy group. The total pulmonary vascular resistance on postoperative day 3 correlated with the plasma BNP concentration in the pneumonectomy group. CONCLUSIONS: A-type NP and BNP effectively compensate for the right ventricular dysfunction noted after pulmonary resection, and this is more evident after pneumonectomy than after lobectomy. Changes in ventricular activity associated with changes in plasma BNP and total pulmonary vascular resistance are indicative of cardiopulmonary adjustments after pneumonectomy.

Aged↗
PubMed2002

Adenoviral herpes simplex virus thymidine kinase gene therapy in an orthotopic lung cancer model.

BACKGROUND: Although adenovirus-mediated herpes simplex virus thymidine kinase (HSVtk) gene therapy is a potential candidate for a novel effective therapy for lung cancer, previous studies have been performed only in a subcutaneous tumor model employing nude mice. We studied therapeutic potentials in correlation with accurate adenoviral gene transduction efficiency in a more clinically relevant orthotopic lung cancer model employing immunocompetent mice. METHODS: To analyze the cytotoxicity of adenoviral HSVtk gene transduction and ganciclovir, a cell proliferation assay was performed in vitro. A survival study was carried out in immunocompetent mice with orthotopic lung cancer, which was generated by intrapulmonary inoculation with syngeneic murine lung cancer cells that had been infected beforehand with each adenoviral vector at the predetermined gene transduction efficiencies. RESULTS: Tumor cells were efficiently killed by infection with adenovirus carrying the HSVtk gene with the addition of ganciclovir in vitro. In the in vivo experiment all control mice died of rapid growth of the primary lung cancer and of metastases to mediastinal lymph nodes within 26 days after tumor inoculation. In contrast 50% and 100% of mice survived more than 40 days after inoculation with adenovirally HSVtk-transfected tumor cells that moderately and highly expressed HSVtk, respectively, when followed by ganciclovir administration. Gene transduction efficiencies were 67%. CONCLUSIONS: Adenovirus-mediated HSVtk gene therapy may be therapeutic for lung cancer when gene transduction efficiencies and sufficient expression levels of HSVtk can be achieved. Moreover, the present findings underscore the importance of the mouse orthotopic lung cancer model for studies of gene therapy.

Adenocarcinoma↗
PubMed2002

Intraoperative intercostal nerve blockade for postthoracotomy pain.

BACKGROUND: Epidural analgesia is widely employed as a means to control postthoracotomy pain, but is sometimes inadequate. The purpose of this study is to evaluate the effectiveness of intraoperative, temporary, intercostal nerve blockade in addition to epidural analgesia for control of postthoracotomy pain. METHODS: Forty patients undergoing elective lobectomy through antero-axillary thoracotomy were randomized to receive epidural analgesia only (group A, n = 20) or epidural analgesia plus temporary, intraoperative intercostal nerve blockade using 0.25% bupivacaine (group B, n = 20). Postoperative pain was assessed using a subjective analogue visual scale, and with the Prince Henry pain scale. Food intake and nonsteroidal analgesic consumption were also investigated. Serum ACTH and cortisol in each group were measured before and after the operation. RESULTS: The analogue visual scale scores were significantly higher in group A than group B (p < 0.001), and were significantly higher on the day of operation and postoperative days 1, 2, and 3 (p < 0.001, p < 0.005, p < 0.005, p < 0.05, respectively). Prince Henry pain scale scores were significantly higher on the day of operation and postoperative day 1 (p < 0.05, p < 0.005, respectively). Food intake was significantly lower in group A than in group B (p < 0.05), and nonsteroidal analgesic consumption was not significantly different between groups. There was no significant difference between group A and group B in serum ACTH or in cortisol levels. CONCLUSIONS: Additional intraoperative intercostal nerve blockade provides an additive benefit for postthoracotomy pain relief, especially early after operation.

Female↗
PubMed2002

Temporary stenting for malignant tracheal stenosis due to esophageal cancer: a case report.

We present a case of a 56-year-old male with esophageal cancer who underwent successful temporary tracheal stenting followed by a surgical procedure. The trachea was obstructed owing to endotracheal metastasis and the patient had severe dyspnea. A silicone Y-stent was initially inserted into the tracheal stenosis to secure the airway, and then tumor-specific chemo-radiotherapy was applied. The tumor was reduced, the stent was removed and a pathological study indicated that the tracheal metastasis had disappeared. The patient then underwent esophagectomy and tumor-specific chemo-radiotherapy was continued after the surgery. The patient has remained alive and free of esophageal cancer for 18 months after the airway stent emplacement. These findings suggested that the silicone stent was suitable as a temporary measure and that temporary stenting combined with tumor-specific therapy was effective as part of the aggressive therapeutic strategy with which to treat the malignant airway stenosis due to esophageal cancer.

Airway Obstruction↗
PubMed2002

Alveolar adenoma of the lung: computed tomography and magnetic resonance imaging findings.

Alveolar adenoma of the lung is a rare benign neoplasm with distinctive gross and microscopic findings. Radiographically, alveolar adenoma usually presents as a well-circumscribed, peripheral, solitary nodule. The authors describe the contrast-enhanced computed tomography and magnetic resonance imaging features of alveolar adenoma of lung. Magnetic resonance imaging demonstrated the presence of a cystic space with central fluid and thin-rim enhancement. These findings are suggestive of a benign nodule, and alveolar adenoma of lung should be added to the differential diagnosis of nodules that demonstrate this pattern of enhancement and are probably benign.

Adenocarcinoma, Bronchiolo-Alveolar↗