Biomedical subjects

S J Mentzer

Publications and source records attributed to S J Mentzer.

At least 37 records · Page 2Linked to original sources

PubMed2000

Surveillance transbronchial lung biopsies: implication for survival after lung transplantation.

OBJECTIVES: We wished to determine whether early rejection after lung transplantation as assessed by surveillance transbronchial biopsy predicts for survival. METHODS: Between 1990 and 1997, 96 consecutive patients had lung transplantation: 89 had a minimum 1-month follow-up. For 71 consecutive patients we have 1-year follow-up and for 69 patients we have the results of the first 3 biopsies. Cytomegalovirus status, bronchiolitis obliterans prevalence, and use of total lymphoid irradiation are noted. Biopsies were done at 1 week and 1, 3, and 6 months. Standard immunosuppression consisted of induction antilymphocyte globulin and high-dose methylprednisolone induction for 1 week and standard maintenance triple therapy. Acute rejection treatment was with pulse methylprednisolone. Bronchiolitis obliterans syndrome was treated with total lymphoid irradiation and a change to tacrolimus and mycophenolate. Blinded grading using International Society for Heart and Lung Transplantation classification was done retrospectively. RESULTS: Survival at 1 month and 1, 2, and 3 years for the 96-patient cohort with 1-year follow-up was 93%, 74%, 62%, and 56%. Survival was not significantly different for subsets with rejection on any combination of the first 3 biopsies (1/3, 2/3, 3/3) or absence of rejection on the first 3 biopsies. Ninety-one positive biopsy results were graded. Eighteen of 71 patients had one or more moderate or severe rejection episodes without survival difference relative to the others. There was no statistically significant association between acute rejection on the first 3 surveillance biopsy results and bronchiolitis obliterans. CONCLUSIONS: Intensive induction and maintenance immunotherapy with surveillance transbronchial biopsies and aggressive treatment of acute rejection is associated with a survival similar to that of patients without early acute rejection. This regimen appears to uncouple the association between early acute rejection and bronchiolitis obliterans. Further study may elucidate this mechanism.

Adolescent↗

PubMed2000

Angiocentric recruitment of lymphocytes into the lung after the intrabronchial instillation of antigen.

The pathogenesis of acute lymphocytic inflammation in the lower respiratory tract appears to involve the recruitment of lymphocytes out of the blood stream and into the extravascular lung tissue. To investigate the membrane molecules regulating this process, we used the intrabronchial instillation of cellular antigen to trigger lymphocyte recruitment into the lower respiratory tract. Sheep presensitized 6 to 10 weeks earlier at a remote site were intrabronchially challenged with 1-5 x 10(7) cells from a B lymphoblastoid cell line. The cells were instilled into a subsegmental bronchus through a bronchial catheter. The stimulated and contralateral control segments were studied at a peak of inflammation, approximately 72 hours after antigen stimulation. Gross and microscopic studies of the stimulated segment demonstrated localized inflammation characterized by the perivascular infiltration of lymphocytes. In contrast, control areas of the lung demonstrated only scattered perivascular lymphocytes. Immunohistochemistry of the stimulated lung showed that the majority of these perivascular cells were CD3+ CD4+ lymphocytes. The T lymphocytes expressed high levels of the cell adhesion molecules beta 1 integrin and LFA-1, but low levels of the L-selectin membrane molecule. Immunohistochemistry of the endothelial cells associated with the lymphocyte infiltrates demonstrated intense staining of the ICAM-1, and beta 1 integrin adhesion molecules. Electron microscopic studies of the endothelial cells in the antigen stimulated areas of the lung confirmed morphologic changes consistent with endothelialitis. These results suggest that the intrabronchial instillation of cellular antigen stimulates an angiocentric T-cell infiltration regulated by activated pulmonary endothelial cells. The histologic and morphologic findings are remarkably similar to those observed during acute lung transplant rejection.

Animals↗

PubMed2000

Generation of sheep X (sheep X mouse) heterohybridoma cell line expressing the beta-1 integrin membrane molecule.

Sheep are an important biological model in such diverse areas as immunology and reproductive biology. The limitation of sheep as an experimental model is the absence of reliable cell lines. To establish cell lines that express functional sheep membrane molecules, we produced a sheep x mouse heterohybridoma by fusion of sheep efferent lymph T cells with the murine myeloma cell line NS1. A cloned heterohybridoma fusion partner was selected by treatment with 8-azaguanine. The resulting cell line HL1/385 was selected for hypoxanthine/aminopterin/thymidine (HAT) sensitivity and growth efficiency. The HL1/385 cell line was used as a back-fusion partner into lectin-stimulated efferent T lymphocytes. The back-fusion approach produced more than 50 heterohybrid cell lines with high growth efficiency. The expression of physiological levels of the sheep beta-1 integrin cell surface molecule on the HT4/6 cell line was stable for months in culture. These results suggest that somatic heterohybrids may provide a reliable source of cell lines for sheep studies in vitro.

Animals↗

PubMed1999

Pretreatment staging by endoscopic ultrasonography does not predict complete response to neoadjuvant chemoradiation in patients with esophageal carcinoma.

BACKGROUND: Endoscopic ultrasonography (EUS) provides highly accurate preoperative T and N classifications in patients with esophageal carcinoma. Although previous data have suggested that patients with tumors classified as T4 by EUS do not benefit from surgical resection, these data were acquired prior to the widespread use of preoperative chemoradiation. The current study investigated whether pretreatment EUS can predict a complete response to neoadjuvant therapy. METHODS: Patients with esophageal carcinoma (adenocarcinoma or squamous cell carcinoma) underwent EUS classification prior to therapy. Patients classified as T2, T3, or T4 and M0 were treated with 5-fluorouracil, cisplatin, and radiation under protocol. Patients with T1 lesions underwent resection without prior chemoradiation. Chemoradiation was followed in all cases by attempted surgical resection. The initial EUS classification was compared with the final pathologic results. RESULTS: Fifty-five patients (47 males and 8 females) with a mean age of 60.5 years (range, 31-78 years) were evaluated. There were 41 adenocarcinomas and 14 squamous cell carcinomas. Among the total population, a complete response was achieved in 3 of 5 patients (60%) with tumors classified as T2 by EUS, 14 of 42 patients (33%) with tumors classified as T3 by EUS, and 5 of 8 patients (63%) with tumors classified as T4 by EUS (P = 0.19). A complete response was achieved in 9 of 24 patients (38%) found to have N0 disease by EUS versus 13 of 30 patients (43%) determined to have N1 disease (P = 0.66). The results for patients with adenocarcinoma and squamous cell carcinoma were similar. CONCLUSIONS: The results of the current study demonstrate that pretreatment EUS does not predict reliably which patients with esophageal carcinoma will achieve a complete pathologic response to preoperative neoadjuvant chemoradiation.

Adenocarcinoma↗

PubMed1999

Resection margins, extrapleural nodal status, and cell type determine postoperative long-term survival in trimodality therapy of malignant pleural mesothelioma: results in 183 patients.

OBJECTIVES: Our aim was to identify prognostic variables for long-term postoperative survival in trimodality management of malignant pleural mesothelioma. METHODS: From 1980 to 1997, 183 patients underwent extrapleural pneumonectomy followed by adjuvant chemotherapy and radiotherapy. RESULTS: Forty-three women and 140 men (age range 31-76 years) had a median follow-up of 13 months. The perioperative mortality rate was 3.8% (7 deaths) and the morbidity, 50%. Survival in the 176 remaining patients was 38% at 2 years and 15% at 5 years (median 19 months). Univariate analysis identified 3 prognostic variables associated with improved survival: epithelial cell type (52% 2-year survival, 21% 5-year survival, 26-month median survival; P =.0001), negative resection margins (44% at 2 years, 25% at 5 years, median 23 months; P =.02), and extrapleural nodes without metastases (42% at 2 years, 17% at 5 years, median 21 months; P =.004). Using the Cox proportional hazards, the relative risk of death was calculated for nonepithelial cell type (OR 3.0, CI 2.0-4.5; P <.0001), positive resection margins (OR 1.7, CI 1.2-2.6; P =.0082), and metastatic extrapleural nodes (OR 2.0, CI 1.3-3.2; P =.0026). Thirty-one patients with 3 positive variables had the best survival (68% 2-year survival, 46% 5-year survival, median 51 months; P =.013). A previously published staging system using these variables stratified survival (P <.05). CONCLUSIONS: (1) Multimodality therapy including extrapleural pneumonectomy is feasible in selected patients with malignant pleural mesotheliomas, (2) pre-resectional evaluation of extrapleural nodes may select patients for radical therapy, (3) microscopic resection margins affect long-term survival, highlighting the need for further investigation of locoregional control, and (4) patients with epithelial, margin-negative, extrapleural node-negative resection had extended survival.

Adult↗

PubMed1999

Causes of allograft dysfunction after single lung transplantation for emphysema: extrinsic restriction versus intrinsic obstruction. Brigham and Women's Hospital Lung Transplantation Group.

BACKGROUND: A subset of patients with emphysema who have undergone single lung transplantation (SLT) may subsequently present with dyspnea, worsening airways obstruction, hypoxemia, and progressive chronic native lung hyperinflation. The leading cause of late allograft dysfunction is bronchiolitis obliterans syndrome (BOS). However, extrinsic restriction manifests with a similar clinical presentation and is an additional mechanism to consider. We describe the use of the inspiratory lung resistance (RLi) to distinguish a decline in respiratory status due predominantly to either extrinsic restriction or BOS. METHODS: We studied five patients who underwent SLT for emphysema between 1992 and 1995, in whom the diagnoses of BOS and extrinsic restriction were subsequently entertained. Forced expiratory volume in 1 second (FEV1), RLi, static lung compliance, elastic recoil pressure at total lung capacity (TLC), and the slope of the maximum flow static recoil (MFSR) plot were measured. RESULTS: All patients had severe airflow obstruction, with mean FEV1 0.98 +/- 0.24 liter (26 +/- 5% predicted), elevated static lung compliance, reduced elastic recoil pressure at TLC, and reduced slope of the MFSR plot. Three patients had "low" RLi (9.3-12.8 cm H20/L/sec). Obstruction was attributed predominantly to extrinsic restriction. These patients underwent lung volume reduction surgery (LVRS) on the native lung; improvements in pulmonary mechanics were observed at 6 months. In contrast, two patients had markedly elevated RLi (17.3 and 17.4 cm H2O/L/sec). Obstruction was attributed predominantly to intrinsic airway disease from BOS that was subsequently documented at autopsy. CONCLUSIONS: The RLi appears to be a useful adjunct to the clinical history in distinguishing a decline in respiratory status due predominantly to either BOS or extrinsic restriction in patients who have undergone SLT for emphysema. Determination of the mechanism of allograft dysfunction may allow the selection of an appropriate subset of patients who would benefit from LVRS.

Airway Resistance↗

PubMed1999

Patterns of recurrence and outcome for patients with clinical stage II non-small-cell lung cancer.

Forty-six patients with pathologic clinical stage II non-small-cell lung carcinoma underwent resection with or without adjuvant radiotherapy from 1989 through 1994. These patients were analyzed to determine patterns of recurrence and survival. Surgery consisted of pneumonectomy for 11 patients, bilobectomy for two patients, lobectomy for 29 patients, and wedge or segmental resection for four patients. Adjuvant radiotherapy was delivered to 29 patients, and the median total dose was 54 Gy (range, 44-60 Gy). Median follow-up time was 23 months for all patients and 25 months for surviving patients. Twenty-six of 46 patients have had recurrence. The site of first recurrence was locoregional for 9 of 46 patients (20%) and distant for 17 of 46 patients (37%). The median time to locoregional recurrence was 18 months for patients treated with radiotherapy and 13 months for patients treated without radiotherapy. An isolated locoregional recurrence (with no simultaneous distant recurrence) was seen in 2 of 28 evaluable patients (7%) treated with radiotherapy compared with 3 of 17 patients (18%) not treated with radiotherapy. For all patients, the 3-year disease-free survival rate was 52%, and the overall survival rate was 52%. Among patients treated with radiotherapy, the 3-year disease-free survival and overall survival rates were 56% and 56%, respectively, compared with 46% and 43%, respectively, for patients who did not receive radiotherapy (p values were not significant). The locoregional recurrence rate was 33% for patients with adenocarcinoma and 15% for those with squamous cell carcinoma. The distant recurrence rates by histologic characteristic were 56% and 20%, respectively. For patients with clinical stage II non-small-cell lung cancer, postoperative radiotherapy appears to improve locoregional control. However, the preponderance of recurrences remains distant. Further study is warranted with special emphasis on control of systemic disease.

Adult↗

PubMed1999

Model of functional restriction in chronic obstructive pulmonary disease, transplantation, and lung reduction surgery.

Mechanical interactions between lung and chest wall are important determinants of respiratory function. When chest wall expansion during maximal inhalation generates insufficiently negative pleural pressures, the lungs remain functionally underinflated; this may be termed functional restriction. To explore mechanisms and effects of functional restriction in patients with emphysema, and to predict effects of single lung transplantation and lung volume reduction surgery (LVRS), we used a computational model based on standard physiology and measurements from individual patients. The model's lungs, separated by a compliant mediastinum, exhibit flow limitation according to the equal pressure point approach of Mead and coworkers. Pulmonary elastic recoil pressure is characterized by an exponential equation modified to reflect airway closure. Simulated respiratory maneuvers can be specified by variations in flow or pressure at the airway opening or in respiratory muscle activation. Model simulations successfully mimic recordings from individual patients. Input parameter values may then be altered to predict effects of surgical interventions in these same patients. The model simulations show the following. Single lung transplantation in emphysema can cause functional restriction of the normal transplanted lungs, and larger transplanted lungs may perform less well than smaller ones. LVRS improves lung and chest wall function in emphysema, but not in normal states. Surgical reduction of the native emphysematous lung after single lung transplantation can reduce functional restriction of the transplant and thereby improve its function.

Humans↗

PubMed1999

Health-related quality of life improves following pulmonary rehabilitation and lung volume reduction surgery.

STUDY OBJECTIVES: To evaluate changes in health-related quality of life (HRQL) as assessed by the Medical Outcomes Study Short Form 36-item questionnaire (SF-36) after pulmonary rehabilitation and lung volume reduction surgery (LVRS). DESIGN: Prospective cohort study. PATIENTS: Nineteen patients with severe emphysema who underwent pulmonary rehabilitation in preparation for LVRS. INTERVENTIONS: Pulmonary rehabilitation followed by bilateral sequential LVRS. MEASUREMENTS AND RESULTS: HRQL assessed by the SF-36 was measured at baseline, after pulmonary rehabilitation, and 6 months after LVRS. One-way analysis of variance with repeated measures demonstrated no significant change from baseline in any of the eight domains after pulmonary rehabilitation. Scores for only one domain, vitality, improved significantly after LVRS compared with scores after pulmonary rehabilitation. However, significant improvements over baseline scores were demonstrated after combined preoperative pulmonary rehabilitation and LVRS in the domains of physical functioning, role limitations due to physical problems, social functioning, and vitality. Pulmonary rehabilitation contributed most to the overall improvements in role limitations due to physical problems, whereas LVRS contributed mainly to the overall improvements in physical functioning, social functioning, and vitality. CONCLUSIONS: Patients with severe emphysema experience significant improvements in both physical and social health status as assessed by the SF-36 after combined pulmonary rehabilitation and LVRS. Each intervention makes unique and complementary contributions to the overall improvements in HRQL.

Aged↗

PubMed1999

Treatment of patients with lung cancer and severe emphysema.

The development of lung cancer and emphysema is associated with the destructive chemical milieu that occurs with smoking. The recent interest in lung volume reduction surgery (LVRS) has stimulated a reassessment of the indications for surgery in patients with early stage lung cancer or emphysema. For patients with both diseases, the issues surrounding LVRS are simplified. The major concern is that the lung cancer can be surgically removed without the need for postoperative ventilation or mortality. A secondary consideration is the potential for long-term postoperative respiratory morbidity. These risks can be estimated by evaluating the anatomic location of the tumor, as well as the physiology of the underlying emphysema. Early results of combined LVRS and lung cancer resections suggest a favorable outcome in carefully selected patients.

Humans↗

PubMed1999

New surgical options for elderly lung cancer patients.

To understand the size of the aging population in the United States, the imminent need to include the elderly in clinical studies on lung cancer, and the safe potential of video-assisted thoracic surgery, and to change awareness of the elderly's need for and ability to undergo treatment for lung cancer, clinical studies of video-assisted thoracic surgery in patients > or = 70 years of age are presented. The elderly are a fast-growing part of the American population who are at high risk for lung cancer and should be included in clinical studies. Age alone should not be a contradiction to thoracic surgical interventions when video thoracoscopy is performed as treatment.

Age Factors↗

PubMed1999

Management of the solitary pulmonary nodule: role of thoracoscopy in diagnosis and therapy.

OBJECTIVES: The solitary pulmonary nodule remains a common clinical problem. The essential question is whether the lesion is malignant or not. This discussion presents the clinical practice and looks at the problem. DESIGN: Didactic. SETTING: Academic tertiary-care hospital. PATIENTS: Prospective thoracic database. INTERVENTIONS: Minimally invasive technique. RESULTS: The workup and treatment of the solitary pulmonary nodule is presented with particular emphasis on the role of minimally invasive techniques. A small single-institution series is referenced. CONCLUSIONS: The approach is safe and highly effective in diagnosing and often in treating solitary pulmonary nodules.

Carcinoma, Non-Small-Cell Lung↗

PubMed1998

Relation between preoperative inspiratory lung resistance and the outcome of lung-volume-reduction surgery for emphysema.

BACKGROUND: Surgery to reduce lung volume has recently been reintroduced to alleviate dyspnea and improve exercise tolerance in selected patients with emphysema. A reliable means of identifying patients who are likely to benefit from this surgery is needed. METHODS: We measured lung resistance during inspiration, static recoil pressure at total lung capacity, static lung compliance, expiratory flow rates, and lung volumes in 29 patients with chronic obstructive lung disease before lung-volume-reduction surgery. The changes in the forced expiratory volume in one second (FEV1) six months after surgery were related to the preoperatively determined physiologic measures. A response to surgery was defined as an increase in the FEV1 of at least 0.2 liter and of at least 12 percent above base-line values. RESULTS: Of the 29 patients, 23 had some improvement in FEV1 including 15 who met the criteria for a response to surgery. Among the variables considered, only preoperative lung resistance during inspiration predicted changes in expiratory flow rates after surgery. Inspiratory lung resistance correlated significantly and inversely with improvement in FEV1 after surgery (r=-0.63, P<0.001). A preoperative criterion of an inspiratory resistance of 10 cm of water per liter per second had a sensitivity of 88 percent (14 of 16 patients) and a specificity of 92 percent (12 of 13 patients) in identifying patients who were likely to have a response to surgery. CONCLUSIONS: Preoperative lung resistance during inspiration appears to be a useful measure for selecting patients with emphysema for lung-volume-reduction surgery.

Adult↗

PubMed1998

Clinical radiation pneumonitis and radiographic changes after thoracic radiation therapy for lung carcinoma.

BACKGROUND: The authors attempted to determine the incidence of and risk factors for clinical radiation pneumonitis in patients treated for lung carcinoma. They also sought to describe the corresponding posttreatment radiographic changes. METHODS: Between 1989-1993, 83 patients received curative radiation therapy for lung carcinoma. Of these, 39 patients were treated with definitive radiation therapy, and 44 patients were treated with adjuvant radiation therapy after surgical resection. The median radiation therapy dose was 54 gray (Gy), and the median treatment area was 182 cm2. Chest radiographs obtained after radiation therapy were reviewed and scored for margin definition, volume loss, and texture quality. RESULTS: A total of 17 patients (20%) developed clinical radiation pneumonitis (CRP). The median radiation therapy dose for the CRP cohort was 54 Gy, and the median treatment volume was 193 cm2. The median time to onset of symptoms was 3 weeks after radiation therapy, and the median duration of symptoms was 10 weeks. Of the 15 evaluable patients, symptoms resolved for 9 patients, improved but persisted for 4 patients, and CRP was fatal for 2 patients. The incidence of CRP was increased for patients with low performance status, comorbid lung disease, smoking history, low pulmonary function tests, and for those patients who did not undergo a surgical resection. Posttreatment radiographic changes were common and progressed with time. Radiographic changes were more pronounced in the CRP cohort, and extended outside the radiation therapy treatment field in the majority of patients (67%). CONCLUSIONS: Clinical radiation pneumonitis developed in 20% of lung carcinoma patients. Risk factors included low performance status, comorbid lung disease, smoking history, low pulmonary function tests, and the absence of a surgical resection. Posttreatment radiograph changes were common and progressed with time, and typically were not confined to the radiation therapy treatment field.

Adult↗

PubMed1998

Arginine butyrate-induced susceptibility to ganciclovir in an Epstein-Barr-virus-associated lymphoma.

Lymphoproliferative disorders associated with Epstein-Barr virus (EBV) infections can occur in the setting of immunosuppression. In some patients, the lymphoproliferative disorder can resemble an aggressive monoclonal non-Hodgkins lymphoma (NHL). These NHL are poorly responsive to conventional therapy. Similarly, antiviral therapy with synthetic nucleosides such as ganciclovir are ineffective because the genes that render the virus susceptible to therapy are not expressed in EBV+ lymphomas. Using a cell line derived from a lung transplant recipient with an EBV+ immunoblastic NHL, we studied the ability of arginine butyrate to induce the expression of EBV thymidine kinase. Arginine butyrate was not only effective in inducing EBV thymidine kinase transcription, but also acted synergistically with the antiviral agent ganciclovir to inhibit cell proliferation and decrease cell viability. Based on these findings, the patient from whom the cell line was derived was treated with arginine butyrate/ganciclovir as well as conventional cytotoxic chemotherapy. No additional toxicity was observed with the arginine butyrate/ganciclovir therapy. Histologic examination of the tumor showed substantial necrosis. These observations suggest the feasibility of arginine butyrate induction of ganciclovir susceptibility in patients with EBV-associated lymphomas.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1998

Inflammatory cell distribution within and along asthmatic airways.

Asthmatic airways are infiltrated with inflammatory cells that release mediators and cytokines into the microenvironment. In this study, we evaluated the distribution of CD45-positive leukocytes and eosinophils in lung tissue from five patients who died with severe asthma compared with five patients with cystic fibrosis. For morphometric analysis, the airway wall was partitioned into an "inner" area (between basement membrane and smooth muscle) and an "outer" area (between smooth muscle and alveolar attachments). Large airways (with a perimeter greater than 3.0 mm) from patients with asthma or cystic fibrosis had a greater density of CD45-positive cells (p < 0.05) and eosinophils (p < 0.001) in the inner airway region compared with the same airway region in small airways. Furthermore, in small airways, asthmatic lungs showed a greater density of CD45-positive cells (p < 0.01) and eosinophils (p < 0.01) in the outer compared with the inner airway wall region. These observations indicate that there are regional variations in inflammatory cell distribution within the airway wall in patients with asthma that are not observed in airways from patients with cystic fibrosis. We speculate that this inflammatory cell density in peripheral airways in severe asthma may relate to the peripheral airway obstruction characteristic of this condition.

Adolescent↗

PubMed1997

Patterns of failure after trimodality therapy for malignant pleural mesothelioma.

BACKGROUND: Malignant pleural mesothelioma is uncommon, and presently, no standard treatment of this disease exists. The objective of our analysis was to study the patterns of failure for malignant pleural mesothelioma after trimodality treatment consisting of extrapleural pneumonectomy, chemotherapy, and radiation therapy. METHODS: Between 1987 and 1993, 49 patients with malignant pleural mesothelioma underwent extrapleural pneumonectomy. There were two perioperative deaths, and 1 patient died 5 weeks after extrapleural pneumonectomy. Thirty-five of the surviving patients received adjuvant chemotherapy (32/35 received cyclophosphamide, doxorubicin, and cisplatin) followed by hemithorax radiation therapy. Ten patients received chemotherapy but no radiation therapy, and 1 patient received no adjuvant therapy. Median follow-up time for the 23 living patients from the date of operation was 18 months. RESULTS: Of the 46 evaluable patients, 25 had recurrence (54%), with a median time to first failure of 19 months (range, 5 to 51 months). The sites of first recurrence were local in 35% of patients, abdominal in 26%, the contralateral thorax in 17%, and other distant sites in 8%. (Some patients had recurrence in multiple sites simultaneously.) CONCLUSIONS: The most common site of failure after trimodality therapy was the ipsilateral hemithorax. Isolated distant failures were uncommon. Future strategies should investigate methods of enhancing local tumor control.

Abdominal Neoplasms↗

PubMed1997

Mediastinoscopy, thoracoscopy, and video-assisted thoracic surgery in the diagnosis and staging of lung cancer.

The surgical approach to the diagnosis and staging of lung cancer requires the assessment of the lung parenchyma, hilum, pleura, chest wall, and intrathoracic lymph nodes. Chest computerized tomography is sensitive in defining the location of the primary tumor, but is relatively insensitive to invasion. Similarly, radiographic imaging can identify lymph node enlargement, but lymph node enlargement alone is insufficient for accurate staging. To facilitate the tissue biopsies of both the primary tumor and potential sites of metastatic disease, video thoracoscopy has provided a useful complement to traditional bronchoscopy and mediastinoscopy. These instruments provide minimally invasive access to the lung, pleura, and ipsilateral lymph nodes. The combined application of thoracoscopy, bronchoscopy, and mediastinoscopy can provide intrathoracic staging information while minimizing surgical morbidity.

Humans↗