Single-agent gemcitabine in patients with resistant small-cell lung cancer

OBJECTIVE

This study was conducted to assess the activity and toxicity ofgemcitabine in patients with resistant small-cell lung cancer (SCLC). PATIENTS TAND METHODS: Forty-one patients with limited- or extensive-stage SCLC, who were previously treated with at least one chemotherapeutic regimen and progressed during or within three months of finishing the last regimen, were treated with 1000 mg/m2 gemcitabine on days 1, 8, and 15 of a four-week cycle.

RESULTS

Thirty-eight patients were evaluable for response. Five partial and no complete responses were seen, for an overall response rate of 13% (95% confidence interval (CI): 6%-27%). Time to progression varied from 4 to 20 weeks, with a median of 8 weeks. Median survival was 17 weeks (range 4-84 weeks). Hematological toxicity mainly consisted of NCI-CTC grade 3 thrombocytopenia (29% of patients) and, to a lesser extent, grade 3 leukopenia (18% of patients). Non-hematological toxicity was mild, with nausea being the most commonly reported event.

CONCLUSIONS

Gemcitabine has modest activity in patients with resistant SCLC. There is some non-cross resistance to most agents against SCLC.

Treatment of relapsed small cell lung cancer

Small cell lung cancer is a frequently relapsing tumor despite a high rate of response after first-line chemotherapy. For these patients, treatment at relapse depends on the response to first-line treatment, time off therapy, and the site of progression. For patients with a good performance status and a relapse more than 3 months after first-line treatment, the choice of chemotherapy at relapse is the same as initial therapy. In case of earlier progression, so-called non-cross-resistant chemotherapy should be given. For symptomatic metastases in bone or brain, radiotherapy usually gives temporary palliation. For intrathoracic relapse and severe obstruction of main bronchus and/or superior caval vein, radiotherapy is a possibility if not given as part of first-line treatment. Semin Oncol 28 (suppl 4):48-52.

Photodynamic therapy, Nd-YAG laser and electrocautery for treating early-stage intraluminal cancer: which to choose?

The degree of healing and damage of the bronchial wall after photodynamic therapy, Nd-YAG laser and electrocautery for intraluminal early-stage cancer have been analysed. Review of the bronchoscopy reports and follow-up histology specimens of twenty-nine patients treated bronchoscopically with curative intent for their intraluminal tumor have been performed. Seventeen patients had been treated with bronchoscopic electrocautery (BE) only, six with photodynamic therapy (PDT) and six with Nd-YAG laser. Bronchial wall scarring seen during follow-up bronchoscopy was scored and subepithelial fibrosis were histologically evaluated using Alcian blue staining, Azan staining and polarised light. After BE, prominent airway scarring was seen in five patients (29%), with significant stenosis (>50% lumen) in one of these cases. Prominent scarring and significant stenosis were found in four (67%), after PDT. In five (83%) after Nd-YAG laser prominent scarring was found, one patient had significant stenosis. In three cases, two after BE and one after PDT, subepithelial tissue in the follow-up biopsies was insufficient for proper histologic examination. In the remaining biopsy specimen only one (7%) showed a moderate or excessive amount of fibroblasts after BE, whereas for PDT and Nd-YAG this was found in three (60%) and four patients (67%), respectively. Excessive matrix was found in none of the biopsies after BE, in two (40%) after PDT and in three (50%) after Nd-YAG laser. Compact collagen formations were seen in two (12%) biopsies after BE, in two (40 and 33%) after PDT and Nd-YAG, respectively. Compared to electrocautery, more airway scarring and more subepithelial fibrosis were seen after treatment with PDT and Nd-YAG laser. These findings, especially regarding PDT, is in contrast to the assumption that PDT is selective and may be important in the choice of treatment for patients with early stage cancer.

Schedule-dependent pharmacodynamic effects of gemcitabine and cisplatin in mice bearing Lewis lung murine non-small cell lung tumours

The combination of 2',2'-difluorodeoxycytidine (gemcitabine, dFdC) and cis-diammine-dichloroplatinum(II) (cisplatin, CDDP) is increasingly applied in clinical oncology. We studied the underlying mechanisms of the in vivo schedule dependency and supraadditive interaction between dFdC and CDDP in C57/B16 mice bearing Lewis lung (LL) tumours. Mice were treated with CDDP (6 mg/kg) and dFdC (60 mg/kg) either simultaneously or in a 4 or 24 h interval with dFdC preceding CDDP or vice versa. Four, 8 (in some cases 12) and 24 h after treatment mice were sacrificed and tumours, kidneys, blood and bone marrow (BM) were collected. Since CDDP acts by formation of Platinum (Pt)-DNA adducts and dFdC by incorporation of its triphosphate (dFdCTP) into DNA, we measured total Pt levels, dFdCTP accumulation and Pt-DNA adducts by atomic absorption spectrometry (AAS), high performance liquid chromatography (HPLC) and 2P-postlabelling, respectively. These levels were related to the previously determined antitumour efficacy and toxicity of the dFdC/CDDP combination. Peak dFdCTP accumulation in tumours (11 pmol/mg) was found 4 h after dFdC treatment, while CDDP tended to reduce this in a time-dependent way. Peak levels of total Pt in tumours were found 4 h after CDDP treatment (581 fmol/mg) and dropped 1.8-fold after simultaneous treatment with dFdC (P = 0.04). Treatment with dFdC 4 h after or simultaneously with CDDP increased Pt retention (level 24 h after CDDP treatment) 1.4- and 1.6-fold (P = 0.04 and P = 0.03, respectively). Peak Pt-DNA adduct levels in tumours were also found 4 h after CDDP treatment (7 fmol/microg DNA) and were decreased 3-fold by dFdC treatment 24 h prior to CDDP (P = 0.04). Pt-DNA adduct retention was only decreased when dFdC was given 4 h before CDDP (8-fold (P < 0.01)). The retention and the area-under the concentration time curve of Pt-DNA adducts were related to decreased tumour doubling time (linear regression coefficient (R) = 0.95; P < 0.05, 0.96 P = 0.04 and 0.90; P = 0.04. Pt-DNA adduct levels in the BM cells reached a plateau level 4-24 h after CDDP treatment (approximately 10 fmol/microg DNA), which was increased by dFdC when given either simultaneously with, 4 h before or 4 h after CDDP (6-, 3- and 5-fold at 28 h, 8 h and 28 h, respectively (P < or = 0.04)). Peak Pt-DNA adduct formation (24 h: 8 fmol/microg DNA) in kidneys was enhanced by dFdC when given simultaneously with or 4 h before CDDP (4 h timepoint) (P < 0.01). However, retention was 4- and 6-fold decreased when dFdC was given 4 or 24 h after CDDP, respectively (P < or = 0.01). dFdC given 24 h before CDDP decreased all Pt-DNA adduct levels in kidneys 3-fold or more (P < or = 0.03). Pt-DNA adduct levels were inversely related to kidney toxicity when the most toxic schedule was excluded from the analysis. Peak levels of total Pt in kidneys were reached 24 h after CDDP treatment (4.3 fmol/mg) and the 8 h levels were increased 2-fold by dFdC when given 4 h after CDDP (P = 0.07).

Monitoring of recruitment and derecruitment by electrical impedance tomography in a model of acute lung injury

OBJECTIVE

To evaluate a noninvasive system for obtaining information about alveolar recruitment and derecruitment in a model of acute lung injury.

DESIGN

Prospective experimental study.

SETTING

Animal research laboratory.

SUBJECTS

Nine anesthetized pigs.

INTERVENTIONS

Electrical impedance tomography measurements were performed. Electrical impedance tomography is an imaging technique that can register the ventilation-induced impedance changes in different parts of the lung. In nine anesthetized pigs, repeated lung lavages were performed until a PaO2 of <80 mm Hg was reached. Thereafter, the lungs were recruited according to two different recruitment protocols: the open lung approach and the open lung concept. Five time points for measurements were chosen: healthy (reference), lavage (atelectasis), recruitment, derecruitment, and maintain recruited (final).

MEASUREMENTS AND MAIN RESULTS

After lavage, there was a significant increase in the impedance ratio, defined as the ventilation-induced impedance changes of the anterior part of the lung divided by that of the posterior part (from 1.75 +/- 0.63 to 4.51 +/- 2.22; p < .05). The impedance ratio decreased significantly after performing the recruitment protocol (from 4.51 +/- 2.22 to 1.18 +/- 0.51). During both recruitment procedures, a steep increase in baseline impedance change was seen. Furthermore, during derecruitment, a decrease in the slope in baseline impedance change was seen in the posterior part of the lung, whereas the anterior part showed no change.

CONCLUSION

Electrical impedance tomography is a technique that can show impedance changes resembling recruitment and derecruitment of alveoli in the anterior and posterior parts of the lung. Therefore, electrical impedance tomography may help in determining the optimal mechanical ventilation in a patient with acute lung injury.

Diagnosing acute pulmonary embolism: effect of chronic obstructive pulmonary disease on the performance of D-dimer testing, ventilation/perfusion scintigraphy, spiral computed tomographic angiography, and conventional angiography. ANTELOPE Study Group. Advances in New Technologies Evaluating the Localization of Pulmonary Embolism

In patients with chronic obstructive pulmonary disease (COPD), differentiating a pulmonary embolism (PE) from an exacerbation of COPD can be difficult, since clinical signs and symptoms of the two conditions overlap. Development of reliable noninvasive or minimally invasive techniques for the diagnosis of PE is, especially in these patients, necessary. In this study we assessed the effect of COPD on the accuracy of the clinical probability estimate (CPE), spiral computed tomographic angiography (SCTA), D-dimer analysis, ventilation perfusion (V/Q) scintigraphy, and pulmonary angiography for the diagnosis of PE. From May 1997 through March 1998, 627 consecutive patients with suspected PE were investigated in six teaching hospitals. In these patients, D-dimer testing, CPE, V/Q scintigraphy, and SCTA and/or pulmonary angiography were performed according to a strict diagnostic protocol. The patients were also independently categorized as having COPD or not. A diagnosis of COPD was established in 91 patients (15%). The prevalence of PE was similar in patients with and without COPD (29% and 31%, respectively), notwithstanding the larger proportion of nondiagnostic V/Q scan results in patients with COPD (46% versus 21%, p < 0.001). The distribution of CPEs, diagnostic value of the D-dimer assay and SCTA, and reproducibility of pulmonary angiography were comparable among patients with and without COPD. The presence of COPD does not affect the diagnostic performance of CPE, D-dimer testing, SCTA, or pulmonary angiography. Furthermore, although more nondiagnostic V/Q scan results can be expected in the presence of COPD, V/Q scintigraphy remains a valuable screening test in patients with COPD.

Second-line chemotherapy in relapsing or refractory non-small-cell lung cancer: a review

PURPOSE

Since the increased use of first-line chemotherapy for non-small-cell lung cancer (NSCLC), second-line chemotherapy may nowadays be considered for a growing group of patients. Guidelines for second-line treatment have to be developed yet.

METHODS

We reviewed the published literature on second-line chemotherapy for NSCLC with emphasis on the role of factors such as pretreatment, response to first-line treatment, and length of disease-free-interval.

RESULTS

Thirty-four single-agent-studies and 24 multidrug-studies on second-line treatment were identified. Docetaxel has been studied most extensively and is the only agent that has been studied in randomized phase III trials. Different definitions of sensitivity applied by different authors and conflicting results have been reported about the influence of response to prior chemotherapy.

CONCLUSION

Since most patients are treated with a platinum-based regimen in the first line, platinum resistance usually is a major consideration for the use of second-line agents. We argue, however, that a more general definition of drug resistance is more appropriate than resistance to platinum only. Criteria to select NSCLC patients for second-line treatment have not been defined yet. This is also important in light of the upcoming necessity to test new drugs in pretreated instead of treated patients. Guidelines for second-line treatment of NSCLC based on clinical information on drug sensitivity to first-line therapy need to be developed.

Assessment of sleep complaints and sleep-disordered breathing in a consecutive series of obese patients

BACKGROUND/OBJECTIVE

The prevalence of sleep-related complaints (SRC) and the frequency of sleep-disordered breathing (SDB) in obese patients has not been studied extensively. We investigated SRC and SDB in a group of obese persons as part of a preoperative workup for weight reduction (bariatric) surgery.

METHODS

All consecutive patients attending a weight-loss clinic for evaluation for bariatric surgery were asked to complete a questionnaire. The questionnaire consisted of a section on SRC and a validated general sleep questionnaire (Sleep Wake Experience List). The patients underwent sleep studies in which an Edentrace recorder registered heart rate, chest wall movements by impedance, airflow and oxygen saturation.

RESULTS

Fifty-one patients (14 men, 37 women) were evaluated. Mean body mass index (BMI) was 45 kg/m2 (range 33-61). Eighteen patients (35%) demonstrated SDB, defined as (a) an apnea/hypopnea index 5, and/or (b) more than 2% of registration time with an oxygen saturation below 90%. There was no difference between these 18 patients and patients who did not exhibit SDB in age, sex, BMI or SRC. Seven patients had SDB of a severity warranting closer investigation and perioperative monitoring.

CONCLUSION

Both SRC and SDB are common in obese patients. Limited nocturnal respiratory monitoring is indicated as part of the preoperative workup for weight reduction surgery.

Availability of diagnostic facilities in the Netherlands for patients with suspected pulmonary embolism. ANTELOPE Study Group. Advances in New Technologies Evaluating the Localisation of Pulmonary Embolism

Pulmonary embolism remains a complex diagnostic problem. Although accurate and cost-effective, the 'Dutch consensus' strategy is not widely applied. We assessed the availability and investment plans of the different facilities used in this strategy. Furthermore, the current and future availability of new diagnostic modalities was investigated. A questionnaire was sent to all Dutch hospitals. The questionnaire contained separate sections with questions for the hospital management and the medical practitioners at the departments of radiology, nuclear medicine, internal medicine and pulmonology. Five hundred and eighty-four questionnaires were sent out (response rate 68%). Forty-three percent of the hospitals had no nuclear medicine facility, 11% had no pulmonary angiography facility, and 59% had no spiral CT scan (SCTA). Forty-six percent of the responding hospitals had a nuclear medicine facility; and 5% used Technegas for ventilation studies. Strategies with SCTA were available in about 27% of the hospitals. Due to future investments this number will increase to approximately 55%. Strategies with Technegas were available in 2.4% of the hospitals, this number might increase to 25% if Technegas is proven accurate. The 'Dutch consensus' strategy is available in two-thirds of the hospitals. All other strategies were less feasible. Several equivalent strategies for diagnosing pulmonary embolism should be developed. These strategies should be accurate, widely available and accepted.

Treatment of brain metastases of small-cell lung cancer: comparing teniposide and teniposide with whole-brain radiotherapy--a phase III study of the European Organization for the Research and Treatment of Cancer Lung Cancer Cooperative Group

PURPOSE

Approximately 60% of patients with small-cell lung cancer (SCLC) develop brain metastases. Whole-brain radiotherapy (WBRT) gives symptomatic improvement in more than 50% of these patients. Because brain metastases are a sign of systemic progression, and chemotherapy was found to be effective as well, it becomes questionable whether WBRT is the only appropriate therapy in this situation.

PATIENTS AND METHODS

In a phase III study, SCLC patients with brain metastases were randomized to receive teniposide with or without WBRT. Teniposide 120 mg/m(2) was given intravenously three times a week, every 3 weeks. WBRT (10 fractions of 3 Gy) had to start within 3 weeks from the start of chemotherapy. Response was measured clinically and by computed tomography of the brain.

RESULTS

One hundred twenty eligible patients were randomized. A 57% response rate was seen in the combined-modality arm (95% confidence interval [CI], 43% to 69%), and a 22% response rate was seen in the teniposide-alone arm (95% CI, 12% to 34%) (P<.001). Time to progression in the brain was longer in the combined-modality group (P=.005). Clinical response and response outside the brain were not different. The median survival time was 3.5 months in the combined-modality arm and 3.2 months in the teniposide-alone arm. Overall survival in both groups was not different (P=.087).

CONCLUSION

Adding WBRT to teniposide results in a much higher response rate of brain metastases and in a longer time to progression of brain metastases than teniposide alone. Survival was poor in both groups and not significantly different.

Validation of a polymerase chain reaction aided transcript titration assay (PATTY) for topoisomerase II in lung cancer samples

This report describes the validation of a polymerase chain reaction aided transcript titration assay (PATTY) for tumor samples. The results obtained with the PATTY were compared to those of RNase protection in a set of 7 human lung cancer cell lines and in 23 non-small cell lung cancer samples derived from resected patients. Whereas between PATTY and RNase protection assay a good correlation was observed in the cell lines (r = 0.74, p = 0.057), no correlation was observed within the tumor samples (r = 0.06, p = 0.78). This was also the case when only tumors with a high percentage of tumor cells (> 90%) were selected. Although PATTY is a valuable tool to measure mRNA expression in cell lines, our results caution the use of PATTY in human tumor samples without proper validation. The possible causes of these results are discussed.

Monitoring response to therapy in cancer using [18F]-2-fluoro-2-deoxy-D-glucose and positron emission tomography: an overview of different analytical methods

[18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) is considered a valuable tool in the diagnosis and staging of cancer. In addition, it seems promising as a technique to monitor response to therapy. Progress is hampered, however, by the fact that various methods for the analysis of uptake of FDG in tumours have been described and that it is by no means clear whether these methods have the same sensitivity for monitoring response to treatment. As interest in monitoring response using FDG PET is growing, the danger exists that non-optimal methods will be used for evaluation. Hence an overview of the various analytical methods is given, highlighting both advantages and shortcomings of each of the methods. The ideal analytical method for response monitoring should represent an optimal trade-off between accuracy and simplicity (clinical applicability). At present, that trade-off still needs to be defined. Studies relating response, as measured with any of the available analytical methods, to outcome are urgently needed. Until then response monitoring studies should be conducted in such a way that all analytical methods can be compared with the most quantitative one, which at present is full compartmental modelling of the data.

Outcome of bronchial carcinoma in situ

INTRODUCTION

The proportion of patients with carcinoma in situ in whom invasive cancer will develop is not known. It is important for clinical decision making to know the outcome of these lesions. The same applies for studies assessing the effectiveness of chemoprevention treatment or endobronchial therapy.

METHODS

The records of patients with a bronchial carcinoma in situ who had undergone autofluorescence bronchoscopic examinations at regular intervals during a follow-up period for at least 6 months were reviewed. Data were examined for the outcome of carcinoma in situ, and for the detection, course, and bronchoscopic findings of neoplastic lesions at other bronchial sites.

RESULTS

Progression to carcinoma occurred in five of nine patients (56%) with a carcinoma in situ. Eight neoplastic lesions were detected at other sites in four of the nine patients (44%). In earlier biopsy specimens of two sites that later showed a severe dysplasia and a carcinoma, only normal epithelium was found. Biopsies had been performed at these sites because they were assessed as suspicious during autofluorescence bronchoscopy.

CONCLUSION

The majority of sites showing a carcinoma in situ progressed to invasive carcinoma. A considerable portion of the patients had neoplastic lesions at other bronchial sites. The fluorescence pattern of the bronchial mucosa may reflect early changes that are not found at histopathologic examination, but which may progress to neoplastic growth.

The degree of branching of the glycans of alpha(1)-acid glycoprotein in asthma. A correlation with lung function and inflammatory parameters

Alpha(1)-acid glycoprotein (AGP) is a plasma protein belonging to the group of acute-phase proteins. It contains five N-linked glycans which, depending on pathophysiologic state, differ in their degree of branching (i.e., in the relative proportions of di-, tri-, and tetraantennary glycans). Changes in the degree of branching of these glycans have been shown to affect various immunomodulatory properties of AGP. We wanted to investigate whether changes occur in the branching of AGP glycans in plasma and in bronchoalveolar lavage fluid (BALF) in asthma. For this purpose, we selected three groups of patients for study: patients with atopic asthma (AA), atopic nonasthmatic patients, and a group of patients with various interstitial lung diseases (ILDs). The plasma AGP concentration was normal in both atopic study groups, but was increased in ILD patients. In contrast, the branching of glycans of AGP was altered in subjects with AA, whereas it was normal in the other study groups. The presence of asthma symptoms correlated with the increased glycan branching of AGP in both plasma and BALF. Additionally, the degree of branching of AGP in BALF was related to FEV(1), to the provocative dose of histamine causing a 20% decrease in FEV (PD(20)), and to the number of eosinophils. In conclusion, asthma is accompanied by changes in the branching of AGP glycans that indicate an inflammatory reaction that differs markedly from a normal acute-phase response, in which decreased branching of AGP occurs.

Do bullae indicate a predisposition to recurrent pneumothorax?

A relationship between idiopathic spontaneous pneumothorax (ISP) and visible parenchymal bullae and blebs has been reported. The causal relationship between blebs and bullae and ISP is questionable. Consequently, resection of the involved area is only indicated if it predisposes to recurrence of the pneumothorax. CT studies on 101 cases of ISP were analysed. The presence of bullae and their distribution was then related to the first and recurrent pneumothorax. CT demonstrated bullae in 56% of first ISP and in 64% of recurrent ISP, mostly among older patients. Only eight patients had bullae larger than 2 cm on the side of the pneumothorax. The location of the bullae was not a factor in predicting recurrent pneumothorax.

Untreated idiopathic aneurysm of the pulmonary artery; long-term follow-up

A 57-year-old man with an idiopathic aneurysm of the left pulmonary artery is presented. The aneurysm was stable over many decades. No such long-term follow-up of an idiopathic pulmonary aneurysm has been described previously. After 39 years there is no evidence of heart failure or pulmonary hypertension. Because corrective surgery has a variable outcome, and prognosis is suggested to be good in the idiopathic form of pulmonary aneurysm, no surgical correction was proposed.

Tissue effects of bronchoscopic electrocautery: bronchoscopic appearance and histologic changes of bronchial wall after electrocautery

STUDY OBJECTIVES

To study tissue effects of bronchoscopic electrocautery (BE).

DESIGN

In six patients with non-small cell lung cancer, a BE procedure was performed immediately before surgery. After patients were placed on ventilation, normal mucosa on different carinae was treated with a cautery probe (2-mm(2) surface area) at a power setting of 30 W with a variable time of application of 1 to 5 s. Bronchoscopic appearance of the treated area was documented photographically, and histologic changes of the bronchial wall were examined.

SETTING

Bronchoscopy unit of a university hospital.

MEASUREMENTS AND RESULTS

BE resulted bronchoscopically in whitening of the bronchial mucosa with crater-shaped lesions. After longer duration of BE application, deeper craters with more profound charring were seen. Histologic changes of the lesions showed craters containing a variable amount of necrotic tissue. In one case, thin subsegmental carinae were coagulated and measurements could not be performed. In the remaining five cases, microscopic findings revealed 0.2 +/- 0.1-mm necrosis after 1 s; 0.4 +/- 0.2-mm necrosis after 2 s; 0.9 +/- 0.5-mm necrosis after 3 s; and 1.9 +/- 0.8-mm necrosis after 5 s. A variable degree of tissue damage surrounding the necrotic tissue area was found. In one case, cartilage damage appeared after 3 s of coagulation, and extensive damage of the underlying cartilage was seen in four cases after 5 s of application.

CONCLUSIONS

Superficial damage was obtained by short duration of BE (< or = 2 s), and longer duration of coagulation (3 s or 5 s) caused damage to the underlying cartilage. Bronchoscopic appearance after endobronchial electrocautery corresponded with the histologic changes.

Prediction of peak oxygen uptake in men using pulmonary and hemodynamic variables during exercise

PURPOSE

Many attempts have been made to predict peak VO2 from data obtained at rest or submaximal exercise. Predictive submaximal tests using the heart rate (HR) response have limited accuracy. Some tests incorporate submaximal gas exchange data, but a predictive test without gas exchange measurements would be of benefit. Addition of stroke volume and pulmonary function (PF) measurements might increase the predictability of a submaximal exercise test.

METHODS

In this study, an incremental exercise test (10 W x min(-1)) was performed in 30 healthy men of various habitual activity levels. Step-wise multiple regression analysis was used to isolate the most important predictor variables of peak VO2 from a set of measurements of PF: lung volumes, diffusion capacity, airway resistance, and maximum inspiratory and expiratory pressures; gas exchange; minute ventilation (V(E)), tidal volume (V(T)), respiratory exchange ratio (RER = carbon dioxide output divided by VO2); and hemodynamics (HR, stroke index (SI) = stroke volume/body surface area, and mean arterial pressure). These measurements were made at rest and during submaximal exercise.

RESULTS

Using the set of PF variables (expressed as percentages of predicted), FEV1 explained 30% of the variance of peak VO2. No other PF variables were predictive. After addition of resting hemodynamic data, SI was included in the prediction equation, raising the predictability to 40%. At the 60-W exercise level, 48% of the variance in peak VO2 could be explained by SI and FEV1. At 150 W, the prediction increased to 81%. At this level VCO2/O2 (RER) also entered the prediction equation of peak VO2: 6.44 x FEV1(%) + 13.0 x SI - 1921 x RER + 2380 (SE = 142 mL x min(-1) x m(-2), P < 0.0001). Leaving out the gas exchange variable RER, maximally 64% of the variance in peak VO2 could be explained.

CONCLUSION

In conclusion, inclusion of pulmonary function and hemodynamic measurements could improve the prediction accuracy of a submaximal exercise test. The submaximal exercise test should be performed until a level of 150 W is reached. Noninvasive stroke volume measurements by means of EIC have additional value to measurement of HR alone. Finally, measurement of gas exchange significantly improves the predictability of peak VO2.

Regional pressure volume curves by electrical impedance tomography in a model of acute lung injury

OBJECTIVE

A new noninvasive method, electrical impedance tomography (EIT), was used to make pressure-impedance (PI) curves in a lung lavage model of acute lung injury in pigs. The lower inflection point (LIP) and the upper deflection point (UDP) were determined from these curves and from the traditional pressure-volume (PV) curves to determine whether the PI curves resemble the traditional PV curves. Furthermore, regional differences in the mentioned determinants were investigated.

DESIGN

Prospective, experimental study.

SETTING

Animal research laboratory.

INTERVENTIONS

In nine anesthetized pigs, repeated lung lavage was performed until a Pao2 <80 torr was reached. Thereafter, an inspiratory PV curve was made using a constant flow of oxygen. During the intervention, EIT measurements were performed.

MEASUREMENTS AND MAIN RESULTS

In this study, the LIP(EIT) was within 2 cm H2O of the LIP(PV). Furthermore, it was possible to visualize regional PI curves by EIT. No significant difference was found between the LIP(PV) (21.3+/-3.0 cm H2O) and the LIP(EIT) of the total lung (21.5+/-3.0 cm H2O) or the anterior parts of the lung (21.5+/-2.9 cm H2O). A significantly higher LIP (29.5+/-4.9 cm H2O) was found in the posterior parts of the lung. A UDP(PV) could be found in three animals only, whereas in all animals a UDP(EIT) could be determined from the anterior part of the lung.

CONCLUSIONS

Using EIT, determination of LIP and UDP from the regional PI curves is possible. The obtained information from the regional PI curves may help in understanding alveolar recruitment. The use of this new bedside technique for clinical decision making remains to be examined.

A phase I-II study of gemcitabine and paclitaxel in advanced non-small-cell lung cancer patients

Thirty patients with chemotherapy-naïve advanced non-small-cell lung cancer (NSCLC) were given escalating doses of paclitaxel (150, 175, 200 mg/m2) on day 1 in three consecutive cycles, together with a fixed dose of gemcitabine 1000 mg/m2 on days 1 and 8; cycles were repeated every three weeks. The dose escalation of paclitaxel was feasible in the majority of patients. Subsequently, 30 other NSCLC patients received a dose of 200 mg/m2 paclitaxel with gemcitabine 1000 mg/m2 in a phase II study. The major side effect was mild myelosuppression. A response rate of 24% was achieved in 49 fully evaluable patients. This regimen proved to be safe and easy to administer on an out-patient setting, and constitutes now one of the arms of the current EORTC randomized study for advanced NSCLC.

High-resolution CT in patients with intraluminal typical bronchial carcinoid tumors treated with bronchoscopic therapy

STUDY OBJECTIVE

To evaluate the extent to which high-resolution CT (HRCT) can predict the clinical outcome of bronchoscopic treatment with curative intent in patients with intraluminal typical bronchial carcinoid tumors.

DESIGN

An observational study.

SETTING

Bronchoscopy unit and radiology department of a university hospital.

PATIENTS AND INTERVENTIONS

Eighteen patients with intraluminal typical bronchial carcinoid tumors in the absence of nodal and distant disease were treated with bronchoscopic electrocautery or Nd-YAG laser as an alternative to surgical resection. Prior to treatment, HRCT was performed.

RESULTS

In 10 patients, HRCT showed no peribronchial tumor extension, and 9 of these patients were found to be tumor free after bronchoscopic treatment. So far during follow-up, none of these patients has had a recurrence of the tumor. The median duration of follow-up was 33 months (range, 13 to 68 months). In five patients, HRCT showed signs of peribronchial tumor extension. In three of these patients, specimens taken from biopsies performed after bronchoscopic treatment showed residual tumors, and salvage surgery was carried out. In three patients, HRCT was unable to assess peribronchial tumor extension: in two because of insufficient connective tissue contrast between the hilar structures and in one patient because of suboptimal scan technique.

CONCLUSION

HRCT findings were complementary but not conclusive in patients with intraluminal typical bronchial carcinoid tumors treated with bronchoscopic therapy. However, in a category of patients in whom HRCT showed strictly intraluminal tumors, bronchoscopic resection as an alternative for surgical resection seems justified.

Electrical impedance tomography in the assessment of extravascular lung water in noncardiogenic acute respiratory failure

STUDY OBJECTIVES

To establish the value of electrical impedance tomography (EIT) in assessing pulmonary edema in noncardiogenic acute respiratory failure (ARF), as compared to the thermal dye double indicator dilution technique (TDD).

DESIGN

Prospective clinical study.

SETTING

ICU of a general hospital.

PATIENTS

Fourteen ARF patients.

INTERVENTIONS

In order to use the TDD to determine the amount of extravascular lung water (EVLW), a fiberoptic catheter was placed in the femoral artery.

MEASUREMENTS AND MAIN RESULTS

Fourteen consecutive ARF patients receiving mechanical ventilation were measured by EIT and TDD. EIT visualizes the impedance changes caused by the ventilation in two-dimensional image planes. An impedance ratio (IR) of the ventilation-induced impedance changes of a posterior and an anterior part of the lungs was used to indicate the amount of EVLW. For the 29 measurements in 14 patients, a significant correlation between EIT and TDD (r = 0. 85; p < 0.001) was found. The EIT reproducibility was good. The diagnostic value of the method was tested by receiver operator characteristic analysis, with 10 mL/kg of EVLW considered as the upper limit of normal. At a cutoff level of the IR of 0.64, the IR had a sensitivity of 93%, a specificity of 87%, and a positive predictive value of 87% for a supranormal amount of EVLW. Follow-up measurements were performed in 11 patients. A significant correlation was found between the changes in EVLW measured with EIT and TDD (r = 0.85; p < 0.005).

CONCLUSION

We conclude that EIT is a noninvasive technique for reasonably estimating the amount of EVLW in noncardiogenic ARF.