Biomedical subjects

T Shirakusa

Publications and source records attributed to T Shirakusa.

At least 55 records · Page 3Linked to original sources

PubMed2001

[Carinal resection for lung cancer].

Between January 1993 and March 2000, 16 patients underwent carinal resection for lung cancer; primary carcinoma in 15 patients and recurrent disease in 1. Age ranged from 41 to 74 years old, and the mean age was 58 years. Sleeve pneumonectomy was performed in 8 patients, right upper sleeve lobectomy in 7, and only carinal resection for the recurrent lesion in 1 patient. Combined resection of the aorta was performed in 2 patients, superior vena cava, in 5, left atrium and esophageal wall, in 1, and panpleura, in 1. The 30-day mortality rate was 25.0% (4/16) and the morbidity rate was 50% (8/16). The causes of death were pneumonia, airway bleeding without vascular fistula, brain edema and acute cardiac failure. Anastomotic complication including tracheo-pulmonary vascular fistula and stricture occurred in 2 patients. The 5-year survival rate was 23%.

Adult↗

PubMed2001

[Video-assisted thoracoscopic surgery lobectomy for lung carcinoma].

Video-assisted thoracoscopic surgery (VATS) has been utilized worldwide for the treatment of various types of thoracic disease, in particular for lung carcinoma. The following criteria are accepted as the operative indications for VATS lobectomy: i) clinical T1N1M0: ii) tumor located in the peripheral zone; and iii) non-small cell carcinoma. Videoscopic surgery has the merit of being less invasive, resulting in a low level of postoperative chest pain, short incisional scar, and short duration of hospital stay. Right-side upper mediastinal lymph node dissection is easy under the thoracoscope, although compared with standard thoracotomy it is not always possible to perform complete level II dissection on the left, because of the difficult approach to lymph nodess No. 3 and No. 4 under the aortic arch via the thoracoscope. The postoperative 5-year survival rate after VATS lobectomy is superior to that after standard thoracotomy. It is expected that the indications for VATS will be expanded to include T2 or N1 disease as thorascopic instruments and techniques improve.

Carcinoma, Non-Small-Cell Lung↗

PubMed2001

[Less invasive treatment for lung carcinoma].

Today, less invasive treatments for lung carcinoma are divided to two categories. One is the surgical option which includes 1. surgery by muscle sparing thoracotomy, 2. reduced operation represented by segmentectomy or partial resection, 3. so-called VATS (video-assisted thoracoscopic surgery), and 4. sentinel node navigation surgery. Other options such as photodynamic therapy or brachytherapy are also very useful for the treatment of superficial malignancies at the hilar zone, because of their lower level of invasiveness.

Adenocarcinoma↗

PubMed2001

[Result of surgical treatment to early stage peripheral non-small cell lung cancer].

In the lung cancer, the announcement of the definition, the clinical behavior and the treatment result of the central early stage lung cancer, especially in situ lung cancer, have been seen. However, the definition and a clinicopathological concept of the peripheral lung cancer are still uncertain. The so-called small lung cancer of the tumor diameter 20 mm or less are peripheral lung adenocarcinoma. These patients' prognosis is excellent better, in contradiction to the prognosis of the patients with positive for pleural involvement or vessels invasion is worse. We studied the clinicopathological features, the Noguchi's classification, and prognosis of the 101 patients with small lung adenocarcinoma which were performed the operation, and refere about the selection of the operation method including the VATS and the limited operation.

Adult↗

PubMed2000

Lymph node metastasis and prognosis in small peripheral non-small-cell lung cancers.

OBJECTIVE: The lymph node dissection and curative resection for small peripheral non-small-cell lung cancers, it is essential to know the incidence and distribution of lymph node metastasis to confirm the pathological stage. METHODS: Between January 1984 and August 1996, lobectomy with systemic mediastinal dissection (standard lobectomy) was conducted in 49 patients with small peripheral non-small-cell lung cancers (2.0 cm or less in diameter), and limited resection was conducted in 15 with cardiopulmonary insufficiency. RESULTS: Lymph node metastasis was confirmed histologically in 14 patients undergoing standard lobectomy (28.6%). The incidence of lymph node metastasis was high in tumors with pleural (p2) or subpleural (p1) involvement (63.6%) (7/14). The 5-year survival between standard lobectomy and limited resection patients (83% vs. 71%) was not statistically significant. In patients undergoing standard lobectomy, survival in those with node-negative disease was better than in those with node-positive disease (94% vs. 44%, p < 0.01). CONCLUSIONS: Lymph node involvement, especially in tumors with pleural involvement, is not uncommon, even when tumors are 2.0 cm or less in diameter. Systemic hilar and mediastinal dissection is therefore required for disease staging and treatment.

Aged↗

PubMed2000

Evaluation of the malignant grade of thymic epithelial tumors according to the epithelial subclassification.

We investigated the clinicopathological correlations among 49 surgically resected thymic epithelial tumors (TET), which were subclassified according to the six subtypes established by the Marino, Kirchner, and Müller-Hermelink system, which were renamed as follows: spindle cell type (medullary thymoma), mixed spindle and polygonal cell type (mixed medullary and cortical thymoma), small polygonal cell type (predominantly cortical thymoma), large polygonal cell type (cortical thymoma), atypical type (well differentiated thymic carcinoma), and cytologically malignant type (high-grade thymic carcinoma). The related categories were grouped for statistical analysis as follows: group 1, spindle cell type and mixed type; group 2, small polygonal cell type and large polygonal cell type; group 3, atypical type; group 4, cytologically malignant type. The association of each group with the presence of myasthenia gravis, tumor stage, and the length of survival was studied. Myasthenia gravis was significantly present in patients with small polygonal type, large polygonal type, and atypical type tumors (groups 2 and 3) (P = 0.003). The tumors in group 1 showed the lowest tumor stage while those of group 4 had the most advanced tumor stage (P = 0.002). The patients in group 4 had the worst prognosis, followed by those in group 3, 2, and 1, in that order. The differences among these groups were statistically significant (P = 0.0003). From our results, we determined that TET can be separated into an extremely low-grade malignancy group (group 1), a low-grade malignancy group (group 2), an intermediate malignancy group (group 3), and a high-grade malignancy group (group 4).

Epithelial Cells↗

PubMed2000

Expression of CD44, vascular endothelial growth factor, and proliferating cell nuclear antigen in severe venous invasional colorectal cancer and its relationship to liver metastasis.

The first step in liver metastasis is venous invasion by cancer cells from the primary tumor. However, even among cases where the histology shows extensive venous invasion by the primary tumor, we sometimes find cases without synchronous liver metastases. As a result, there is a strong possibility that, besides the established causes of colorectal cancer and that of cancer cells invading the veins, some other important causes for liver metastasis must exist. We investigated the expression rates of CD44, proliferating cell nuclear antigen (PCNA), and vascular endothelial growth factor (VEGF) in 28 primary colorectal tumors using immunohistological techniques, and examined an association with liver metastasis. Cases that are strongly positive for CD44 or PCNA have a higher rate of synchronous liver metastases than cases with either no expression or a low expression. We could find no correlation between the VEGF expression and synchronous liver metastasis. In cases with severe venous invasion, VEGF is not correlated with liver metastasis whereas CD44 and PCNA are correlated with liver metastasis. In cases where severe venous invasion is histologically observed, an immunohistochemical analysis for CD44 and PCNA should be done to assess the likelihood of liver metastases.

Adult↗

PubMed2000

Cartilaginous injury limits cryopreservation of tracheal isograft.

OBJECTIVE: Histological recovery of tracheal grafts after cryopreservation was investigated using a rat heterotopic tracheal transplant model in order to evaluate the clinical applicability of tracheal cryopreservation. METHODOLOGY: Heterotopic syngeneic tracheal transplantation was performed between F344 rats. Recipient animals received either a non-cryopreserved or a cryopreserved tracheal graft for direct comparison with regard to the effect of cryo-injury. In the non-cryopreserved group (CP(-)), tracheal segments were transplanted syngeneically between F344 rats immediately after harvest. Grafts were implanted into the abdominal space and wrapped with the greater omentum. In the cryopreserved group (CP(+)), grafts were implanted after cryopreservation for 7 days at -85 degrees C. Recipient rats were killed on days 7, 14, 21, 28, and at 2 months after surgery. Epithelial regeneration and cartilage changes were evaluated using a semiquantitative four grade scoring system. RESULTS: Squamous epithelium without ciliated structure was observed on day 7 in both groups. Bronchial epithelium was then regenerated gradually and normally ciliated epithelium was observed on day 28 in both groups. The condition of the epithelium was still well maintained in the CP(-) group at 2 months post-transplantation; however, a severe epithelial defect was observed in the CP(+) group. Bronchial cartilage showed a normal shape and mostly viable chondrocytes with proliferative cell nuclear antigen (PCNA) positive staining at all time points in the CP(-) group until 2 months after surgery. However, in the CP(+) group, a massive loss of viable chondrocytes was observed at 2 months post-transplantation. Macroscopically, CP(+) grafts showed a diminished structure without satisfactory airway lumen at 2 months. CONCLUSION: The epithelium of a tracheal graft can be temporarily recovered after implantation followed by 7 days cryopreservation. However, bronchial cartilage may be severely damaged by freezing, which results in late destruction with loss of viable chondrocytes. It is suggested here that establishing a method of safe cryopreservation for tracheal cartilage will be imperative to making tracheal cryopreservation possible.

Abdomen↗

PubMed2000

Implantation of ultraflex nitinol stents in malignant tracheobronchial stenoses.

STUDY OBJECTIVE: To assess the uncovered Ultraflex nitinol stent (Boston Scientific; Natick, MA) for its efficacy and safety. DESIGN, SETTING, AND PATIENTS: Between October 1997 and October 1998, we carried out a prospective multicenter study at six hospitals in Japan. Fifty-four Ultraflex stents were inserted in 34 patients with inoperable malignant airway stenosis using a flexible and/or a rigid bronchoscope under fluoroscopic and endoscopic visualization. MEASUREMENTS AND RESULTS: Clinical, endoscopic examination, and pulmonary function on days 1, 30, and 60 after stent implantation showed improvement. In 19 patients (56%), stent implantation was performed as an emergency procedure because of life-threatening tracheobronchial obstruction. Immediate relief of dyspnea was achieved in 82% of the patients. The dyspnea index improved significantly after implantation (before vs. days 1, 30, and 60; p<0.001). Significant improvements were observed in obstruction of airway diameter (81+/-15% before vs. 14+/-17% on day 1, 12+/-12% on day 30, and 22+/-28% on day 60; p<0.001). Vital capacity (VC), FEV(1), and peak expiratory flow (PEF) increased significantly after stent implantation: before vs immediately after VC (p<0.01), FEV(1) (p<0.001), and PEF (p<0.05). The main complications were tumor ingrowth (24%) and tumor overgrowth (21%). After coagulation with an Nd-YAG laser or argon plasma coagulation, mechanical coring out using the bevel of a rigid bronchoscope was necessary in patients showing tumor ingrowth or overgrowth. Removal and reposition were possible in case of misplacement. There were no problems with migration and retained secretions. The median survival time of patients was 3 months. The 1-year survival rate was 25.4%. CONCLUSIONS: In this study of the Ultraflex nitinol stent, we have demonstrated that patients were relieved from dyspnea, which contributed to improved quality of life, with minimal complications. This stent can be used safely, even in the subglottic region. Owing to its excellent flexibility and biocompatibility, the stent is also indicated in certain complicated situations, eg, narrow stenosis, hourglass stenosis, curvilinear stenosis, bilateral mainstem bronchial stenoses, and long stenosis of varying diameters.

Adult↗

PubMed2000

[Clinical evaluation of VATS lobectomy for lung cancer].

Thoracoscopic lobectomy is now recognized as a possible less invasive surgical option for stage I primary non-small cell lung cancer. We have widely used thoracoscopic procedure for surgical diagnosis of lung nodules especially in lung peripheral region as well as resection of primary lung cancer. Results of 47 thoracoscopic lobectomy during last 5 years were compared with 24 standard lobectomy under postero-lateral thoracotomy. There were no significant differences in the duration of surgery, post-operative hospital stay, intraoperative blood loss and post-operative survival. All but three patients who were diagnosed as n 2 disease or tumor with extrapulmonary extension post-operatively are surviving at the time of survey. We conclude that thoracoscopic lobectomy is safe and less invasive procedure compared to standard thoracotomy. We believe it can provide sufficient outcome for stage I non-small cell lung cancer.

Aged↗

PubMed2000

[Surgical treatment for severe pulmonary emphysema].

Volume reduction surgery (VRS) has been adopted for patients with severe pulmonary emphysema who complain of continuous exertional dyspnea in daily life. VRS comprises two types of surgical procedure: resection of the peripheral lung by median sternotomy; and the thoracoscopic approach. The latter is considered to be less invasive and better tolerated by patients in poor physical condition, while the former has the disadvantage of heavier bleeding during surgery. However, postoperative air leakage tends to be much less with median sternotomy compared to thoracoscopic VRS.

Humans↗

PubMed2000

[Postoperative results under the new stage classification of lung cancer: the additional reports for those of JACS in 1996].

This time, in 3008 lung cancer patients, the postoperative results were analyzed under the new stage grouping of TNM classification. All of those patients underwent the operation in 1989, and the 5 year-survival rates had beeb surveyed in 1996 by JACS (The Japanese Association for Chest Surgery). Under the new TNM classification established in 1996 worldwidey, T3N0M0 was transferred from IIIA to IIB. This report is the additional one in the focus of the results accompanied with the change of TNM classification.

Humans↗

PubMed1999

Relationship between Fas-ligand expression on carcinoma cell and cytotoxic T-lymphocyte response in lymphoepithelioma-like cancer of the stomach.

The Fas/Fas-ligand (Fas-L) system is involved in the induction of apoptosis and mediates T-cell cytotoxicity. We investigated the Fas/Fas-L system and cytotoxic T lymphocytes (CTLs) in 30 lymphoepithelioma-like cancer of the stomach (LECS) in order to understand the immune evasion of the tumor cells. Epstein-Barr virus (EBV) was detected in 15 cases in 30 LECSs. The expressions of Fas and Fas-L in tumor cells, and TIA-1, CD4, CD8 and CD56 in lymphocytes were examined by immunohistochemical staining. Apoptosis of tumor cells and lymphocytes was detected by the terminal deoxynucleotidyl-mediated dUTP-nick end labeling method (TUNEL). Expression of Fas and Fas-L was detected in tumor cells in 10 and 17 LECS, respectively. CTL consisted predominantly of CD8 (CD8(+) > CD4(+)), whereas natural killer (NK) cells were detected in 4 cases only. In Fas-L-positive tumors, the TIA-1-positive lymphocyte count was significantly lower (p < 0.05) and the number of apoptotic lymphocytes was significantly higher (p < 0.05) than in Fas-L-negative cases. The number of TIA-1-positive lymphocytes in EBV(+) cases was significantly higher than that in the EBV(-) tumors (p < 0.05). The number of apoptotic tumor cells in EBV(+) tumors was significantly lower than in EBV(-) cases (p < 0.01). Our results suggest that in LECS, tumor cells expressing Fas-L may evade the immune attack by killing lymphocytes through the Fas/Fas-L system. However, in EBV(+) LECS tumors, our results indicate that a high number of CTL is associated with a reduction in the number of apoptotic tumor cells. Our findings indicate that the Fas/Fas-L system plays a role in immune evasion of tumor cells in EBV(+) tumors. Int. J. Cancer (Pred. Oncol.) 84:339-343, 1999.

Aged↗

PubMed1999

p53 mutations predict non-small cell lung carcinoma response to radiotherapy.

In vitro and animal studies, the effect of loss of p53 function on radiosensitivity is controversial. p21Waf1/Cip1 is a potent inhibitor of cyclin-dependent kinases and p21 gene polymorphisms are associated with some human cancers. We sought to determine whether p53 mutations or p21 polymorphisms affect response to radiotherapy in patients with recurrent non-small cell lung carcinoma (NSCLC). Thirty-four patients with NSCLC who underwent radiotherapy for recurrent tumors after potentially curative resection were studied. Gene alterations or polymorphisms were analyzed in DNA from the primary tumor tissue, and the response to radiotherapy was based on the metastatic lesion. Mutations in exons 5-8 of the p53 gene were detected by polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. p21 gene polymorphisms were identified by restriction digestion (BsmAI or PstI) of PCR products. Mutations in p53 were found in 13 of 34 patients (38.2%). The response rates (complete plus partial) were 15.4% for patients with tumors having p53 mutations and 61.9% for patients with wild-type p53 (P = 0.013). There was no significant difference between p21 polymorphisms and response to radiation. p53 gene mutations predict response to radiotherapy in NSCLC. Our results provide clinical support for the in vitro model that loss of p53 function decreases radiosensitivity.

Adult↗

PubMed1999

Lung volume reduction surgery results in pulmonary emphysema. Changes in pulmonary function.

From December 1993 to August 1998, we conducted 57 lung volume reduction surgeries on patients with severe pulmonary emphysema but without giant bullae. Of these, 26 underwent unilateral lung volume reduction surgery and 31 bilateral surgery. We analyzed the results of thoracoscopic lung volume reduction surgery (unilateral: 25; bilateral: 16) and volume reduction surgery by median sternotomy (unilateral: 1; bilateral: 15). Bilateral surgery via thoracoscope and median sternotomy significantly improved symptoms and pulmonary functions; mean improvement in forced expiratory volume in 1 second was 42.4% for bilateral thoracoscopic volume reduction surgery and 60.0% for median sternotomy. Unilateral volume reduction surgery produced a mean improvement in forced expiratory volume in 1 second of 28.9%. No significant complications were seen with either procedure. Reevaluation at 1 and 2 years after lung volume reduction surgery showed improvement to be well maintained.

Aged↗

PubMed1999

Video-assisted thoracoscopic esophagomyotomy for achalasia after pulmonary lobectomy.

A 52-year-old man developed achalasia and a lung abscess due to aspiration pneumonia. We conducted a right upper lobectomy by thoracotomy for the abscess and, 2 weeks later, video-assisted thoracoscopic myotomy and fundoplication (modified Belsey Mark IV procedure) though the left thorax for achalasia. Three months after surgery, the patient was free of dysphasia and chest pain and had regained his original weight. Esophageal myotomy and fundoplication using video-assisted thoracoscopy appear to be feasible in treating achalasia involving impaired pulmonary function.

Endoscopy↗

PubMed1999

A lung metastasis from giant cell tumor of bone at eight years after primary resection.

We report a case of extensive pulmonary metastasis from a histologically benign giant cell tumor. A 34-year-old woman had undergone tumor resection, curettage and artificial bone grafting for giant cell tumor in the left tibia. At eight years after surgery, a chest radiograph revealed an extensive tumor shadow in the right thoracic cavity. Tumor resection with right upper and middle bilobectomy was performed. Its histological features were consistent with those of the primary tumor of the tibia. Distant metastases from a giant cell tumor of bone are rare, with only 50 reported cases. Metastasis has occurred mainly within 3 years after the primary resection. However, in 20% of reported cases, metastasis occurred after 5 years or longer. Long-term follow-up and careful observation for distant metastasis are necessary for this histologically benign disease.

Adult↗

PubMed1999

Video-assisted thoracoscopic esophagectomy for esophageal cancer.

BACKGROUND: The Ivor-Lewis procedure is a radical, invasive, and effective procedure for the resection of most esophageal cancers. To minimize invasiveness, we performed thoracoscopic and video-assisted esophagectomy and mediastinal dissection for esophageal cancer. METHODS: From November 1995 to June 1997, 23 patients with intrathoracic esophageal cancer, excluding T4 cancers, underwent thoracoscopic and video-assisted esophagectomy. Bilateral cervical dissections were performed as well as preparation of the gastric tube and transhiatal dissection of the lower esophagus. The cervical esophagus was cut using a stapler knife, and esophageal reconstruction was performed through the retrosternal route or anterior chest wall. Next, thoracoscopic mediastinal dissection and esophagectomy were performed. RESULTS: The mean volume of blood loss was 163 +/- 122 ml; mean thoracoscopic surgery duration, 111 +/- 24 min; mean postoperative day for patients to start eating, 8 +/- 3 days; and mean hospital stay, 26 +/- 8 days. No patient developed systemic inflammatory response syndrome postoperatively. Tracheal injury occurred and was repaired during the thoracoscopic approach in one patient. No patients died within 30 days after surgery. Postoperative complications included transient recurrent nerve palsy in five patients, pulmonary secretion retention requiring tracheotomy in two, and chylothorax in one. Five patients died of cancer recurrence within 1 year of surgery. CONCLUSIONS: Our surgical experience with thoracoscopic and video-assisted esophagectomy indicate that it is a feasible and useful procedure.

Blood Loss, Surgical↗