Preoperative chemotherapy for esophageal cancer with paclitaxel and carboplatin: results of a phase II trial.

OBJECTIVE: Paclitaxel has one of the highest response rates when used as a single agent in patients with esophageal cancer. The combination of paclitaxel and carboplatin has been shown to be a well-tolerated and safe regimen in non-small cell lung cancer. The objective of this study was to determine the efficacy of preoperative paclitaxel and carboplatin in patients with carcinoma of the esophagus. PATIENTS AND METHODS: A phase II trial was initiated in January 1999 and concluded in January 2001. All patients had potentially resectable disease (including clinical T4 lesions). Patients with stage I disease and those with visceral metastases were excluded. All underwent preoperative computed tomography scanning and endosonography for staging. Paclitaxel (200 mg/m(2)) and carboplatin (area under the curve = 6) were given on days 1 and 22. Esophagectomy was carried out on weeks 6 to 8. RESULTS: Twenty-six (11 epidermoid, 15 adenocarcinoma) patients completed the trial. Median age was 61.5 and 85% were men. Preoperative staging showed: stage IIA, 6 patients; stage IIB, 1 patient; and stage III, 19 patients. All patients completed their preoperative chemotherapy. There was no unexpected chemotherapy-related toxicity. A major clinical response was achieved in 16 patients (61%: 19% complete, 42% partial). Resectability was 77% (20/26). A complete pathologic response was seen in 11% of all patients and in 25% of those with epidermoid cancer. Hospital mortality and morbidity were 4 and 27%, respectively. Overall 3-year survival was 48% (64% for resected patients, median not reached). All 6 unresectable patients died within 6 months of exploration. CONCLUSION: Paclitaxel-carboplatin combination is a safe and well-tolerated regimen for esophageal cancer with clinical response rates comparable to historical controls. This regimen may be especially suitable for patients with epidermoid cancer, who had a 25% pathological complete response in this report.

Celecoxib, a selective cyclo-oxygenase-2 inhibitor, enhances the response to preoperative paclitaxel and carboplatin in early-stage non-small-cell lung cancer.

PURPOSE: Preclinical studies suggest that treatment with a selective cyclo-oxygenase-2 (COX-2) inhibitor may augment the antitumor effects of chemotherapy. In this study, patients with non-small-cell lung cancer (NSCLC) were preoperatively treated with celecoxib in combination with chemotherapy. End points were toxicity, response rates, and measurement of intratumoral levels of prostaglandin E2 (PGE2). METHODS: In this phase II trial, 29 patients with stages IB to IIIA NSCLC were treated with two preoperative cycles of paclitaxel and carboplatin, as well as daily celecoxib, followed by surgical resection. Levels of PGE2 in the primary tumors and adjacent normal lung tissue were compared in 17 study patients versus 13 controls, who received preoperative paclitaxel/carboplatin without celecoxib. RESULTS: All patients completed preoperative chemotherapy, and 26 completed preoperative celecoxib. The overall clinical response rate was 65% (48% with partial response; 17% with complete response). Grade 3 or 4 neutropenia was observed in 18 patients (62%). Twenty-eight patients were explored and underwent complete resection of their tumors. There were no complete pathologic responses, but seven patients (24%) had minimal residual microscopic disease. The addition of celecoxib to a regimen of paclitaxel and carboplatin abrogated the marked increase in levels of PGE2 detected in primary tumors after treatment with paclitaxel and carboplatin alone. CONCLUSION: In comparison with historically reported response rates, these data suggest that the addition of a selective COX-2 inhibitor may enhance the response to preoperative paclitaxel and carboplatin in patients with NSCLC. Moreover, treatment with celecoxib 400 mg twice daily was sufficient to normalize the increase in PGE2 levels found in NSCLC patients after treatment with paclitaxel and carboplatin. Confirmatory trials are planned.

Intratumoral administration of low doses of an adenovirus vector encoding tumor necrosis factor alpha together with naive dendritic cells elicits significant suppression of tumor growth without toxicity.

Although tumor necrosis factor alpha (TNF-alpha) is a potent cytokine with a myriad of innate immune antitumor properties, systemic administration of TNF-alpha is associated with significant toxicity, limiting the use of the TNF-alpha protein as an antitumor therapeutic. On the basis of the knowledge that dendritic cells (DCs) play a central role in initiating antitumor adaptive immune responses, we hypothesized that intratumoral administration of low doses of an adenovirus encoding TNF-alpha (AdTNF-alpha) together with syngeneic DCs would act synergistically to suppress preexisting tumors. As a model, four different tumor cell lines, all resistant in vitro to the TNF-alpha protein, were implanted in syngeneic mice, and established tumors received intratumor AdTNF-alpha alone or in combination with DCs. At high doses (10(9) PFU), AdTNF-alpha alone suppressed tumor growth, but was associated with systemic toxicity. A 100-fold lower AdTNF-alpha concentration (10(7) PFU) or high doses of the control vector AdNull had no systemic toxicity, but also minimal suppression of tumor growth. In contrast, local administration of the low dose (10(7) PFU) of AdTNF-alpha in combination with syngeneic DCs (AdTNF-alpha + DCs) elicited marked tumor suppression without toxicity. Administration of AdTNF-alpha + DCs into tumors elicited tumor-specific cytotoxic T cells and protected animals against subsequent challenge with the same tumor, suggesting that AdTNF-alpha + DC therapy induced tumor-specific adaptive immune host responses. Consistent with this concept, studies with syngeneic knockout mice showed that MHC class I molecules on DCs as well as CD8(+) T cells were necessary for the antitumor effect of intratumor AdTNF-alpha + DCs. These data demonstrate that the combination of intratumoral administration of the TNF-alpha cDNA together with naive DCs can evoke tumor suppression without systemic toxicity, providing a new paradigm for the use of TNF-alpha as antitumor therapy.

Morbidity and mortality after neoadjuvant therapy for lung cancer: the risks of right pneumonectomy.

BACKGROUND: The risks of complications in patients undergoing thoracotomy after neoadjuvant therapy for nonsmall cell lung cancer remain controversial. We reviewed our experience to define it further. METHODS: All patients undergoing thoracotomy after induction chemotherapy from 1993 through 1999 were reviewed. Univariate and multivariate methods for logistic regression model were used to identify predictors of adverse events. RESULTS: Induction chemotherapy included mitomycin, vinblastine, and cisplatin (179 patients), carboplatin and paclitaxel (152 patients), and other combinations (139 patients). Eighty-five patients (18%) received preoperative radiation. Operations were pneumonectomy (97 patients), lobectomy (297 patients), lesser resection (18 patients), and exploration only (58 patients). Total mortality was 7 of 297 (2.4%) and 11 of 97 (11.3%) for all lobectomies and pneumonectomies, respectively, but mortality was 11 of 46 (23.9%) for right pneumonectomy. Complications developed in 179 patients (38%). By multiple regression analysis, right pneumonectomy (p = 0.02), blood loss (p = 0.01), and forced expiratory volume in one second (percent predicted) (p = 0.01) predicted complications. No factor emerged to explain this high right pneumonectomy mortality rate. CONCLUSIONS: Pulmonary resection after neoadjuvant therapy is associated with acceptable overall morbidity and mortality. However, right pneumonectomy is associated with a significantly increased risk and should be performed only in selected patients.

Adenovirus gene transfer vectors inhibit growth of lymphatic tumor metastases independent of a therapeutic transgene.

Adenovirus (Ad) gene transfer vectors traffic to regional lymph nodes (RLNs) after footpad injections in mice, resulting in localized production of interferon gamma (IFN-gamma). With this background, we evaluated the hypothesis that Ad vector administration may inhibit RLN tumor metastasis independent of the transgene in the expression cassette. Tumors of MM48, a cell line with a propensity toward lymphogenous metastasis, were established in the footpads of syngeneic C3H mice, and E1(-)E3(-) Ad vectors encoding no transgene (AdNull) or encoding an irrelevant transgene (AdCD; Escherichia coli cytosine deaminase with no 5-fluorocytosine administration) were administered (10(10) particles) in a peritumoral location. Both vectors suppressed the growth of tumor in the regional (popliteal) lymph node. This effect was localized to the regional, but not distant, lymph nodes (p < 0.05). Heat inactivation of the vector or decreasing the dose of the vector to 10(9) particles did not suppress RLN growth of the tumor when compared with 10(10) particles of active AdNull (p < 0.05 and p < 0.01, respectively). The ability of an E1(-)E4(-) vector expressing beta-galactosidase (AdRSVbetagal.11) to suppress RLN tumor growth showed that the E4 region of the Ad vector was not responsible for the effect. Blocking either IFN-gamma or natural killer (NK) cells with systemic antibody treatment in immunocompetent mice allowed rapid growth of RLN metastases despite Ad vector administration, and Ad vector injection into the footpads of tumor-free mice induced the accumulation of NK cells in the RLN. These data demonstrate that, in a metastatic murine tumor model, a low dose (10(10) particles) of replication-deficient Ad vectors inhibits RLN metastases independent of a therapeutic transgene, an effect that is mediated, at least in part, by IFN-gamma and NK cells.

Appropriate surgical treatment of resectable non-small-cell lung cancer.

Patients with early-stage non-small-cell lung cancer (NSCLC) should be treated with complete surgical resection whenever possible. Incomplete resections do not cure, and the optimal pulmonary resection is anatomic lobectomy. Limited resections (wedge resection and segmentectomy) are associated with a threefold increase in local recurrence, which translates into decreased survival. The addition of mediastinal lymph node dissection produces the best pathologic staging but has never been shown to improve survival. Resections can be performed through a variety of incisions and even using minimally invasive techniques, but posterolateral thoracotomy seems to provide the best exposure and is used most frequently. Adjuvant radiotherapy in both the preoperative and postoperative settings does not improve survival in patients with resected NSCLC. Similarly, postoperative chemotherapy cannot be advocated in these patients based on the current data. Improved survival has been demonstrated in the randomized setting for patients with locally advanced, resectable disease (N2) using preoperative (induction) chemo(radio)therapy, but the numbers are small. Patients with this stage of NSCLC should be enrolled in induction therapy protocols whenever possible to confirm the efficacy of this approach.

Effects of diltiazem prophylaxis on the incidence and clinical outcome of atrial arrhythmias after thoracic surgery.

OBJECTIVES: We sought to determine whether early prophylaxis with an L -type calcium channel blocker reduces the incidence and morbidity associated with atrial fibrillation/flutter and supraventricular tachyarrhythmia after major thoracic operations. METHODS: In this randomized, double-blind, placebo-controlled study, 330 patients were given either intravenous diltiazem (n = 167) or placebo (n = 163) immediately after lobectomy (> or =60 years) or pneumonectomy (> or =18 years) and orally thereafter for 14 days. The primary end point with respect to efficacy was a sustained (> or =15 minutes) or clinically significant atrial arrhythmia during treatment. RESULTS: Postoperative atrial arrhythmias (atrial fibrillation/flutter = 60; supraventricular tachyarrhythmias = 5) occurred in 25 (15%) of the 167 patients in the diltiazem group and 40 (25%) of the 163 patients in the placebo group (P = .03). When compared with placebo, diltiazem nearly halved the incidence of clinically significant arrhythmias (17/167 [10%] vs. 31/163 [19%], P = .02). The 2 groups did not differ in the incidence of other major postoperative complications or overall duration or costs of hospitalization. No serious adverse effects caused by diltiazem were seen. CONCLUSIONS: After major thoracic operations, prophylactic diltiazem reduced the incidence of clinically significant atrial arrhythmias in patients considered at high risk for this complication.

Adenovirus vector-mediated gene transfer to regional lymph nodes.

Regional lymph nodes (RLNs) possess important immune functions and represent a major pathway of metastasis for solid tumors. Given these facts, the ability to transfer exogenous genes to the RLNs with the goal of manipulating the local immunological milieu would be desirable. On the basis of the hypothesis that a significant proportion of adenovirus (Ad) gene transfer vectors traffic through the lymphatics, E1-E3- Ad vectors were injected into the hind footpad of C3H/He mice and the RLNs assessed for vector trafficking and transgene expression. A low dose (10(9) particles) of an Ad vector encoding the firefly luciferase gene (Ad-CMV.Luc) resulted in luciferase expression only in the injection site and RLNs, with no detectable systemic (liver, spleen, lung) expression. At a higher dose (10(11) particles), some expression could be detected systemically in addition to the RLNs, but at levels in liver 14-fold less than in the RLNs. Transgene expression in the RLNs was transient, peaking at 1 day, decreasing markedly by 7 days. At high doses (10(11) particles), interruption of draining lymphatics decreased the amount of systemic dissemination 22-fold, suggesting that a large proportion of the vector trafficks through the lymphatics before reaching the systemic circulation. Administration of a vector encoding the jellyfish green fluorescent protein gene (AdCMV.GFP, 10(11) particles) showed that transgene expression in the RLNs was primarily in the cortical area. After footpad injection of a fluorescent-labeled Ad vector (Cy3-AdCMV.Null), fluorescent virions were visualized in the draining lymph. Regional lymph collected from animals injected in the footpad with AdCMV.Luc (10(11) particles) contained functional vector. Augmentation of local immune function in the RLNs was achieved by footpad administration of an Ad vector encoding murine IL-12, resulting in high mIL-12 and IFN-gamma levels in the regional, but not distant, nodes. These data demonstrate that expression of exogenous genes in RLNs is easily accomplished with Ad vectors, Ad vector dissemination occurs primarily via the lymphatics after footpad administration in mice, and basic immune functions in the RLNs can be manipulated by Ad-mediated gene transfer in vivo.

Extent of chest wall invasion and survival in patients with lung cancer.

BACKGROUND: The long-term survival after operation of patients with lung cancer involving the chest wall is known to be related to regional nodal involvement and completeness of resection, but it is not known whether the depth of chest wall involvement or the type of resection (extrapleural or en bloc) affects either the rate of local recurrence or survival. METHODS: We retrospectively reviewed the Memorial Sloan-Kettering Cancer Center experience between 1974 and 1993 of 334 patients undergoing surgical exploration for lung cancer involving the chest wall or parietal pleura. RESULTS: Of 334 patients who underwent exploration, 175 had apparently complete (R0) resections, 94 had incomplete (R1 or R2) resections, and 65 underwent exploration without resection. The overall 5-year survival of R0 patients was 32%, of R1 or R2 patients 4%, and of patients undergoing exploration without resection 0%. In the patients undergoing R0 resections, the extent of chest wall involvement was limited to the parietal pleura in 80 patients, and extended into the ribs or soft tissues in 95. The 5-year survival of R0 patients with T3 N0 M0 disease was 49%, T3 N1 M0 disease 27%, and T3 N2 M0 disease 15% (p < 0.0003). Independent of lymph node involvement, a survival advantage was observed in R0 patients if the chest wall involvement was limited to parietal pleura only, rather than invading into the chest wall musculature or ribs. CONCLUSIONS: Survival of patients with lung cancer invading the chest wall after resection with curative intent is highly dependent on the extent of nodal involvement and the completeness of resection, and much less so on the depth of chest wall invasion.

Operative strategies for resection of pulmonary sarcomas extending into the left atrium.

Pulmonary sarcomas may extend into the left atrium through the pulmonary veins, requiring the use of cardiopulmonary bypass for resection. The operative strategy for these complicated resections must account for the laterality of the tumor, the extent of atrial involvement, the severity of local invasion within the hemithorax, and intrinsic surgical heart disease, if present. We discuss these issues using an illustrative case of a patient with a right pulmonary sarcoma extending from the lateral chest wall into the left atrium.

Lobectomy improves ventilatory function in selected patients with severe COPD.

BACKGROUND: Patients often undergo limited resection instead of lobectomy for non-small cell lung cancer because of a low preoperative forced expiratory volume in 1 second (FEV1). Our goal is to define criteria that will preoperatively identify a group of patients who will not lose further function after lobectomy. METHODS: Patients who underwent lobectomy with a preoperative FEV1 of less than 80% of predicted were retrospectively identified. Data collected included preoperative and postoperative pulmonary function tests, age, sex, the lobe resected, and preoperative ventilation-perfusion scan result. RESULTS: Thirty-two patients were included in this study. The median preoperative FEV1 was 60% of predicted (1.65 L) and the mean change in FEV1 was a loss of 7.8% after lobectomy. The patients were divided into two groups. Group 1 (n = 13) had a preoperative FEV1 of less than or equal to 60% of predicted (median, 49%; 1.35 L) combined with an FEV1 to forced vital capacity ratio of less than or equal to 0.6. Group 2 (n = 19) includes all other patients (median preoperative FEV1, 69% of predicted; 1.87 L). The mean changes in FEV1 after lobectomy were +3.7% and -15.7% for groups 1 and 2, respectively (p < 0.005). A chronic obstructive pulmonary disease index was defined and then calculated for each patient. The relationship between this index and the change in FEV1 after lobectomy for all 32 patients appears linear (r = -0.43; p = 0.015). CONCLUSIONS: Patients with a very low preoperative FEV1 and FEV1 to forced vital capacity ratio are less likely to lose ventilatory function after lobectomy and may actually improve it.

Proposed revision of the staging classification for esophageal cancer.

OBJECTIVES: This study analyzed survival with respect to lymph node involvement to develop a new staging system for patients with esophageal cancer that accurately reflects prognosis. METHODS: The records of patients undergoing resection of primary esophageal cancer from 1989 to 1993 were reviewed. The data collected included patient age and sex, tumor histologic characteristics and location, the use of preoperative or postoperative radiation and chemotherapy, the type of resection, the depth of tumor invasion, the number and location of benign and malignant lymph nodes in the resected specimen, the disease status at last follow-up, and the first site of relapse. With an anatomically specific lymph node map, tumors designated in the current American Joint Committee on Cancer system as M1 because of extensive lymph node metastases were reclassified as N2, reserving the M1 category for visceral metastases. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were assessed by log-rank and Cox regression analyses. RESULTS: There were 216 patients (159 men, 57 women) with a median age of 63.5 years. Adenocarcinoma of the distal esophagus or gastroesophageal junction was the most common tumor (127 patients, 59%) and Ivor Lewis esophagogastrectomy was the most frequently performed operation. Both lymph node location (N1 versus N2) and number (0 vs 1 to 3 vs 4 or more) significantly influenced survival. CONCLUSIONS: A new staging system that adds an N2 M0 descriptor and reclassifies stage groupings reflects prognosis more accurately than does the current American Joint Committee on Cancer staging system. The number of positive lymph nodes is also an important stratification factor.

Cervicothoracic tumors: results of resection by the "hemi-clamshell" approach.

OBJECTIVES: Our goal was to describe the "hemi-clamshell" approach for the resection of primary and metastatic tumors of the cervicothoracic junction, evaluate its morbidity and mortality, and present survival data on a series of 42 patients who underwent resection with the use of this technique. METHODS: We conducted a retrospective review of the records of all patients of a single surgeon undergoing resection of tumors of the cervicothoracic junction. Data collected includes tumor type and involvement, type of resection, complications, and survival. RESULTS: Forty-two patients underwent resection of various primary (n = 28) and metastatic (n = 14) tumors of the cervicothoracic junction over 6.5 years by means of the hemi-clamshell approach. En bloc resection of the tumor and invaded structures was successful in all but two patients (5%), who required an additional posterolateral thoracotomy to facilitate removal of tumor invading the posterior chest wall. Invaded structures that were resected included lung (n = 22), vertebral body (n = 7), chest wall (n = 8), central veins (n = 10), thyroid (n = 3), carotid artery (n = 1), and cervical esophagus (n = 1). Four major complications occurred in three patients, and nine minor complications occurred in eight patients. There were no deaths. The overall 5-year actuarial survival was 67.4%. CONCLUSIONS: Tumors of the cervicothoracic junction are represented by a variety of histologic types and can be both primary and metastatic. The hemi-clamshell approach is a successful technique for the exposure and resection of these tumors. This approach has significant advantages over other previously reported techniques. The complication rate is low and the mortality rate is zero in this series, the largest yet reported. Long-term survival is acceptable if complete resection can be performed.

Atraumatic gastric transposition after transhiatal esophagectomy.

Transhiatal esophagectomy using the stomach for esophageal replacement requires that the gastric "neoesophagus" be transferred from the peritoneal cavity through the posterior mediastinum into the neck under blind conditions. This process is associated with stretching, tearing, and hematoma formation in the most critical portion of the gastric tube, that to be used for the anastomosis. A technique is described for this procedure that is simple to perform and, most importantly, completely atraumatic to the gastric conduit.

Extent of resection and lymphadenectomy in early Barrett's cancer.

The recognition of Barrett's esophagus as a premalignant condition has led to aggressive endoscopic screening protocols aimed at detecting adenocarcinoma in this organ. This policy has resulted in an increasing number of patients who present with 'early Barrett's cancer'. In the existing literature, very little data address patients with these lesions and, therefore, no consistent definition of early Barrett's cancer currently exists. Additionally, the extent of resection and lymphadenectomy that should be performed is not known. We define early Barrett's cancer as clinical T1N0M0 adenocarcinoma. We perform en bloc esophagectomy with radical lymphadenectomy for these lesions because current data suggest that a more radical operation may improve survival in patients with esophageal cancer. It is also the only way to stage adequately the tumour and is associated with morbidity and mortality rates comparable to less radical, 'standard' resections in experienced hands. Barrett's esophagus is associated with invasive adenocarcinoma in 40% of patients who undergo esophagectomy for the preoperative diagnosis of high-grade dysplasia. The existing literature suggests these lesions may represent the earliest subset of Barrett's cancer and that a standard, less radical resection may suffice for these patients.

Complete lobar collapse following pulmonary lobectomy. Its incidence, predisposing factors, and clinical ramifications.

STUDY OBJECTIVE: To define the most severe form of postlobectomy atelectasis and determine its incidence, predisposing factors, and clinical ramifications. DESIGN: Retrospective case control. SETTING: The thoracic surgery unit at a 900-bed tertiary care hospital. PATIENTS OR PARTICIPANTS: Two hundred eighteen patients undergoing pulmonary lobectomy or bilobectomy over a 7-year time period. MEASUREMENTS AND RESULTS: Severe postlobectomy atelectasis (SPLA) was defined as complete ipsilateral lobar or bilobar collapse with whiteout of the involved lobe(s) and mediastinal shift on the chest radiograph. Data were collected consisting of patient age, lobe(s) resected, type of postoperative pain control, length of hospital and ICU stay, preoperative pulmonary function, and single- vs double-lumen tube intubation during surgery. The incidence of SPLA was 7.8%, comprising 24.6% of all postoperative complications seen. There was no statistically significant difference in patient age, preoperative room air PO2, and preoperative FEV1/FVC ratio for the SPLA group vs the group without this complication. Patients with SPLA had significantly longer ICU stays (112.7 h vs 28.4 h; p < 0.001) and hospital stays (14.7 days vs 9.3 days; p < 0.001) than the patients without complications. Patients undergoing right upper lobectomy, both alone or in combination with the right middle lobe, had a significantly higher incidence of SPLA when compared with all other types of resections (15.5% vs 3.0%; p < 0.005). There was no influence on the incidence of SPLA when the types of postoperative pain control regimen and endotracheal tubes used were examined. CONCLUSIONS: We conclude that SPLA as defined in this study is an important postoperative complication with a significant incidence. Although patients undergoing right upper lobectomy are markedly predisposed to this problem, the exact pathophysiology remains unclear. Factors shown to be causes of less severe forms of postoperative atelectasis do not seem to contribute to the formation of SPLA, indicating that these two complications may be two unrelated entities.

In vitro and in vivo transfer and expression of human surfactant SP-A- and SP-B-associated protein cDNAs mediated by replication-deficient, recombinant adenoviral vectors.

Congenital pulmonary alveolar proteinosis (CPAP) is a fatal disease of full-term infants that is unresponsive to current medical therapy. It is now recognized that at least some forms of this disorder are associated with a deficiency of SP-B, one of the surfactant-associated proteins, as well as probable aberrations in the surfactant-associated proteins SP-A and SP-C. Given these developments, it is logical to hypothesize that CPAP may be amenable to gene therapy, in which the human SP-B cDNA, and possibly the cDNAs of the other surfactant associated proteins, are transferred to the epithelium of the lower respiratory tract. We constructed replication-deficient, recombinant adenovirus vectors in which a constitutive viral promoter drives the expression of the DNAs for the surfactant-associated proteins, SP-B (AdCMV.SP-B) and SP-A (AdCMV.SP-A). Following infection of the human lung A549 epithelial cell line with these vectors in vitro, the appropriately sized mRNAs for these cDNAs were detected, whereas cells infected with a control virus or uninfected cells produced none. Western blots demonstrated expression of these proteins, including appropriate processing of the hydrophobic protein, SP-B. Following in vivo intratracheal infection of rats with these vectors, Northern analysis of the lungs revealed appropriately sized mRNAs for these cDNAs whereas rats infected with control virus or uninfected rats show no hybridization with the human surfactant-associated protein probes. In the AdCM-V.SP-A-infected rats, Western blots confirmed the overproduction of the human SP-A protein in both the bronchoalveolar lavage and lung homogenates compared to controls. Thus, it is feasible to utilize adenovirus vectors to transfer and express the human surfactant associated protein cDNAs in vitro and in vivo, presenting a possible mode of therapy for CPAP, as well as other surfactant deficiency states such as the neonatal respiratory distress syndrome and possibly the adult respiratory distress syndrome.

Gene therapy for the respiratory manifestations of cystic fibrosis.

Cystic fibrosis (CF) is caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The major manifestations are on the airway epithelial surface, with purulent mucus, recurrent infections, chronic inflammation, and loss of lung function. Consequent to mutations in both parental genes, airway epithelial cells have insufficient CFTR function. Because this can be corrected in vitro by transfer of the normal CFTR gene into airway epithelial cells, it is reasonable to hypothesize that the respiratory manifestations of CF could be prevented by transfer of the normal human CFTR cDNA to the airway epithelium in vivo. Over the past 6 years, our laboratory has developed a strategy to accomplish this goal using a replication deficient E1-E3- recombinant adenovirus (Ad) serotype 5 vector containing the normal human CFTR cDNA (AdCFTR). Studies with experimental animals demonstrate that with administration of such a vector to the airways, the human CFTR cDNA could be transferred to the airway epithelium, with expression of the human CFTR cDNA for at least 6 weeks. Extensive preclinical studies in vitro and in vivo demonstrated that the risks to humans were sufficiently low to initiate a Phase I trial using the AdCFTR vector to treat the respiratory manifestations of CF in humans. Following approval by the National Heart, Lung, and Blood Institute Institutional Review Board, the National Institutes of Health Biosafety Committee, the National Institutes of Health Recombinant DNA Advisory Committee, and the Food and Drug Administration, we initiated the first human trial of gene therapy for CF on April 17, 1993. The clinical study is still ongoing, with safety and efficacy data being evaluated, but there is clear evidence that it is feasible to transfer and express the normal CFTR cDNA to the airway epithelium in vivo in individuals with CF.

Factors associated with outcome in blunt aortic injury: a population-based study.

A population-based study was conducted for two contiguous states representing a population of 9.1 million to determine whether age, injury severity score, major complications, and preexisting conditions contribute to the outcome of patients diagnosed with blunt traumatic aortic injury. A secondary analysis reviewed patients with blunt aortic injury admitted over a six-year period to a trauma center located in one of the states to examine other more detailed factors related to mortality. Age was the only variable that correlated statistically with mortality in both populations analyzed. (Region P = .004; trauma center P = .0012) The severity of injury showed a tendency for decreased survival with increasing injury severity score. The elderly (age > or = 55) in both data sets sustained higher mortality from blunt aortic injury. In the trauma center population, the elderly had more delay in diagnosis than the younger patient population.

Validation of respiratory mechanics software in microprocessor-controlled ventilators.

BACKGROUND AND METHODS: Several microprocessor-controlled ventilators, available for clinical use, contain optional computer software programs capable of performing near-instantaneous determinations of airway resistance and lung compliance. This study was undertaken to determine the validity of the measurements for airway resistance and lung compliance obtained by the software packages on three microprocessor-controlled ventilators. Three ventilator models were studied. An artificial ventilator-patient circuit was constructed using a test lung and an endotracheal tube. Airway pressure and gas flow curves were recorded using conventional means. Static lung compliance and airway resistance were calculated using standard equations, while automated measurements were obtained from the ventilators. The following parameters were then varied to simulate a wide variety of clinical situations: tidal volume, peak inspiratory flow rate, respiratory rate, endotracheal tube, and test lung compliance. RESULTS: Automated measurements were highly correlated with values obtained manually (resistance: Puritan-Bennett 7200a r2 = .94, Bear 5 r2 = .98, Veolar r2 = .96; compliance: 7200a r2 = .93, Bear 5 r2 = .97, Veolar r2 = .97). Calculated limits of agreement between the two methods demonstrate that although not in absolute agreement, the software-determined values for airway resistance and lung compliance differed from the manually derived values in a ventilator-specific, predictable fashion. CONCLUSIONS: The correlation and agreement demonstrated between values of airway resistance and lung compliance measured by the respiratory mechanics software packages and those values derived manually suggest that these software packages may be useful for measuring trends, as well as responding to treatment in the clinical setting. These results apply only to the controlled, mechanical ventilation mode. Further studies are indicated to validate this software in patients capable of generating spontaneous breaths.