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P E Postmus

Publications and source records attributed to P E Postmus.

At least 19 recordsLinked to original sources
PubMed2006

NT-proBNP reflects right ventricular structure and function in pulmonary hypertension.

The aim of the current study was to investigate whether alterations in N-terminal pro brain natriuretic peptide (NT-proBNP) reflect changes in right ventricular structure and function in pulmonary hypertension patients during treatment. The study consisted of 30 pulmonary hypertension patients; 15 newly diagnosed and 15 on long-term treatment. NT-proBNP, right heart catheterisation and cardiac magnetic resonance imaging measurements were performed, at baseline and follow-up. There were no significant differences between newly diagnosed patients and those on treatment at baseline or follow-up with respect to NT-proBNP, haemodynamics and right ventricular parameters. Relative changes in NT-proBNP during treatment were correlated to the relative changes in right ventricular end-diastolic volume index (r = 0.59), right ventricular mass index (r = 0.62) and right ventricular ejection fraction (r = -0.81). N-terminal pro brain natriuretic peptide measurements reflect changes in magnetic resonance imaging-measured right ventricular structure and function in pulmonary hypertension patients. An increase in N-terminal pro brain natriuretic peptide over time reflects right ventricular dilatation concomitant to hypertrophy and deterioration of systolic function.

Adult↗
PubMed2006

Multicenter phase II trial of accelerated cisplatin and high-dose epirubicin followed by surgery or radiotherapy in patients with stage IIIa non-small-cell lung cancer with mediastinal lymph node involvement (N2-disease).

To assess the therapeutic activity of accelerated cisplatin and high-dose epirubicin with erythropoietin and G-CSF support as induction therapy for patients with stage IIIa-N2 non-small-cell lung cancer (NSCLC). Patients with stage IIIa-N2 NSCLC were enrolled in a phase II trial. They received cisplatin 60 mg m(-2) and epirubicin 135 mg m(-2) every 2 weeks for three courses combined with erythropoietin and G-CSF. Depending on results of clinical response to induction therapy and restaging, patients were treated with surgery or radiotherapy. In total, 61 patients entered from March 2001 to April 2004. During 169 courses of induction chemotherapy, National Cancer Institute of Canada (NCI-C) grade III/IV leucocytopenia was reported in 35 courses (20.7%), NCI-C grade III/IV thrombocytopenia in 26 courses (15.4%) and NCI-C grade III/IV anaemia in six courses (3.6%). Main cause of cisplatin dose reduction was nephrotoxicity (12 courses). Most patients received three courses. There were no chemotherapy-related deaths. Three patients were not evaluable for clinical response. Twenty-eight patients had a partial response (48.3%, 95% CI: 36-61.1%), 24 stable disease and six progressive disease. After induction therapy, 30 patients underwent surgery; complete resection was achieved in 19 procedures (31.1%). Radical radiotherapy was delivered to 25 patients (41%). Six patients were considered unfit for further treatment. Median survival for all patients was 18 months. Response rate of accelerated cisplatin and high-dose epirubicin as induction chemotherapy for stage IIIa-N2 NSCLC patients is not different from more commonly used cisplatin-based regimen.

Adult↗
PubMed2006

Pharmacology of the paclitaxel-cisplatin, gemcitabine-cisplatin, and paclitaxel-gemcitabine combinations in patients with advanced non-small cell lung cancer.

PURPOSE: To compare the pharmacology of the paclitaxel-cisplatin, gemcitabine-cisplatin and paclitaxel-gemcitabine combinations in patients with advanced non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Twenty-four chemo-naive patients with advanced NSCLC were randomized to receive one of the three regimens. Plasma pharmacokinetics and pharmacologic parameters in mononuclear cells were compared and related to toxicity and efficacy. RESULTS: Pharmacological parameters of gemcitabine and cisplatin were not influenced by the combination with one of the other agents, while the paclitaxel clearance was significantly lower for the combination with cisplatin as compared to gemcitabine (P=0.024). The percentage decrease in platelets was significantly higher for the gemcitabine combinations (P=0.004) and related to the dFdCTP-Cmax (P=0.030). Pharmacologic parameters were not related to response or survival. CONCLUSIONS: Gemcitabine and cisplatin pharmacology were not influenced by the combination with one of the other agents, while paclitaxel has a lower clearance in combination with cisplatin as compared to gemcitabine.

Adult↗
PubMed2005

[Pulmonary arterial hypertension due to the use of amphetamines as drugs or doping].

Pulmonary arterial hypertension (PAH) was diagnosed in three patients. All three had a history ofamphetamine consumption. The patients were a 48-year-old male drug addictwho had used intravenous amphetamine for more than 20 years, a 43-year-old man who had been administered intravenous amphetamines during a period of intensive cycling and a 34-year-old woman who regularly consumed amphetamine at dance festivals. All three patients received medicinal treatment. Amphetamines may lead to PAH due to the release of serotonin, which causes pulmonary vasoconstriction and the proliferation of smooth muscle cells. Due to the pathophysiology of amphetamine-induced PAH, other amphetamine derivatives such as methylenedioxymethamphetamine (ecstasy) and methylphenidate can be risk factors for PAH. These three cases show that PAH should be considered in patients who present with dyspnoea and a reduced exertion tolerance, and who are known to have a history of amphetamine use.

Adult↗
PubMed2005

[The diagnosis of pulmonary embolism: the best strategies according to the results of a large Dutch multicentre study].

The Dutch national guidelines for the diagnosis of patients with clinically suspected pulmonary embolism (from 1992 en 1998) are poorly followed in clinical practice, due especially to practical objections. A large multicentre trial to investigate the diagnostic accuracy of the available modalities and of recently developed techniques such as D-dimer determination, (99m)Tc-gas-scintigraphy and spiral CT scanning was started in I997. In the first phase, the diagnostic value was assessed of: spiral CT (sensitivity 69%, specificity 84%; sensitivity for segmental and larger pulmonary embolisms (PE) 86% and for subsegmental PE 21%), (99m)Tc-gas-ventilation scintigraphy (no improvement compared to conventional ventilation scintigraphy), D-dimer determination (sensitivity for segmental PE 93% and for subsegmental PE 53%, specificity 63%), clinical decision rules (in combination with D-dimer determination; sensitivity 100%, specificity 11%) and echography of the deep venous system (sensitivity 26% for segmental PE and 7% for subsegmental PE, specificity 97%). In the second phase, the feasibility of two new potentially cost-effective diagnostic algorithms was evaluated on the basis of the results obtained in the first phase and data in the literature. In 631 patients, a clinical risk estimate was made and D-dimer determination was done, followed by a ventilation-perfusion scan and serial compression echography of the leg veins. An apparent recurrence of PE occurred in 6 of 466 patients in whom no PE had been found originally (1.3%; 95% CI: 0.5-2.8). The average costs were 812 Euro,--per patient. In 510 patients, a spiral CT followed by compression echography was performed. Recurrent PE occurred in 3 of 378 patients with initial normal tests (0.8%; 95% CI: 0.2-2.3). The average costs were 883 Euro,--per patient. A combination of both strategies can be cost-effective with a cost 674 Euro,--per patient (recurrence rate: 1.9%). Both the strategy starting with a clinical-risk estimate and a D-dimer determination as well as the strategy consisting of spiral CT and serial echography were safe and cost-effective. According to the results of a survey of hospital directors, internists and pulmonologists, both are well accepted in clinical practice.

Algorithms↗
PubMed2005

A randomised phase II trial of docetaxel vs docetaxel and irinotecan in patients with stage IIIb-IV non-small-cell lung cancer who failed first-line treatment.

Response rate and toxicity of second-line therapy with docetaxel (75 mg m(-2)) or docetaxel, irinotecan, and lenogastrim (60 mg m(-2), 200 mg m(-2), and 150 microg m(-2) day(-1), respectively) were compared in 108 patients with stage IIIb-IV non-small-cell lung cancer. Addition of irinotecan to docetaxel does not improve response rate, and increases gastrointestinal toxicity.

Adolescent↗
PubMed2005

Expression of the p16(INK4a) gene product, methylation of the p16(INK4a) promoter region and expression of the polycomb-group gene BMI-1 in squamous cell lung carcinoma and premalignant endobronchial lesions.

It is generally assumed that squamous cell carcinoma develops in a stepwise manner from normal bronchial epithelium towards cancer by the accumulation of (epi)genetic alterations. Several mechanisms including mutations and homozygous deletions or hypermethylation of the p16(INK4a) promoter region can cause loss of p16 expression. Recent studies suggest overexpression of the polycomb-group gene BMI-1 might also down-regulate p16 expression. In this study, we analyzed the p16 expression in relation to the methylation status of the p16 promoter region of the p16(INK4a) gene and the expression of BMI-1 in bronchial squamous cell carcinomas (SCC) and its premalignant lesions. Nine (69%) SCC showed loss of p16 expression and 10 (77%) showed expression of BMI-1. Of four p16 positive samples two (50%) were BMI-1 positive, whereas among nine p16 negative samples, eight (89%) revealed BMI-1 staining. Four (44%) p16 negative samples were hypermethylated at the p16(INK4a) promoter region; the other p16 negative tumors that showed no hypermethylation revealed BMI-1 staining. Only two premalignant lesions showed absence of p16 expression, of which one (carcinoma in situ) was hypermethylated at the p16(INK4a) promoter region and the other (severe dysplasia) showed BMI-1 expression. In total, 11 precursor lesions (48%) revealed BMI-1 expression. In conclusion, the results of this study suggest that loss of p16 expression by promoter hypermethylation is inconsistently and occurs late in the carcinogenic process at the level of severe dysplasia. To what extent overexpression of the polycomb-group protein BMI-1 attributes to down regulating of p16 expression remains unclear.

Aged↗
PubMed2005

Noninvasive assessment and monitoring of the pulmonary circulation.

In pulmonary vascular disease, changes in the pulmonary vascular bed will lead to altered pulmonary haemodynamics. This review describes the application of several physiological principles to measure these changes noninvasively by means of novel techniques. Flow characteristics of blood through the pulmonary vascular bed alter in pulmonary vascular disease. Recent developments in magnetic resonance imaging and computed tomography make it possible to visualise and quantify these abnormal flow patterns. Information regarding pulmonary perfusion can also be obtained by measuring the electrical impedance changes in the lung by electrical impedance tomography. A more indirect approach to measure the pulmonary blood flow is the measurement of the absorption of acetylene, a perfusion limited gas. Information on the pulmonary vascular bed can also be obtained by the measurement of exhaled products of the pulmonary vascular endothelium, such as nitric oxide. Although all the techniques described offer new ways to diagnose or monitor pulmonary vascular disease, clinical data on these techniques are limited. Further improvement and evaluation of the clinical value of these techniques are therefore obligatory before they can be used in clinical practice.

Diagnostic Techniques, Cardiovascular↗
PubMed2004

['Palm reading' as a diagnostic aid].

In four patients, a man aged 53, a woman aged 63 and two men aged 67 and 53 years, respectively, inspection of the hand led to the final diagnosis. In the first patient who presented with clubbing of the fingers and pulmonary hypertension, a small atrial septal defect was detected. The second patient had thick curved yellow nails and recurrent pleural effusions as part of this yellow nail syndrome. The third patient presented with clubbing and hypertrophic osteoarthropathy, a secondary complaint to adenocarcinoma of the lung. The fourth patient had increasing pulmonary hypertension as a secondary complaint to recurrent multiple pulmonary embolism from deep venous malformations of his right hand, arm and shoulder as a part of the Klippel-Trenaunay syndrome. These cases show that inspection of the hand may give a clue to the diagnosis.

Adenocarcinoma↗
PubMed2004

Non-invasive diagnostic work-up of patients with clinically suspected pulmonary embolism; results of a management study.

BACKGROUND: Clinicians often deviate from the recommended algorithm for the diagnosis of pulmonary embolism consisting of ventilation-perfusion scintigraphy and pulmonary angiography. OBJECTIVES: To assess the safety and feasibility of a diagnostic algorithm which reduces the need for lung scintigraphy and avoids the use of angiography. PATIENTS AND METHODS: Consecutive patients with a clinical suspicion of pulmonary embolism were prospectively investigated according to an algorithm in which the diagnosis of pulmonary embolism was excluded after a low clinical probability estimate and a normal d-dimer test result, a normal perfusion scintigraphy result, or a non-high probability scintigraphy result in combination with normal serial ultrasonography of the legs. In these patients anticoagulant treatment was withheld and they were followed up for 3 months to record possible thromboembolic events. During the study period, 923 consecutive patients were seen, of whom 292 were excluded because of predefined criteria. RESULTS: Of the 631 included patients, the diagnosis was refuted on the basis of a low clinical probability estimate and a normal d-dimer test result (95 patients), normal perfusion scintigraphy (161 patients) and non-high probability lung scintigraphy followed by normal serial ultrasonography (210 patients). Of these 466 patients, venous thromboembolic complications during follow-up occurred in six (complication rate 1.3%, 95% confidence interval 0.5, 2.8). The diagnostic protocol was completed in 92% of all included patients. CONCLUSION: The diagnosis of pulmonary embolism can be safely ruled out by a non-invasive algorithm consisting of d-dimer testing combined with a clinical probability estimate, lung scintigraphy, or serial ultrasonography of the legs (in case of non-diagnostic lung scintigraphy).

Algorithms↗
PubMed2003

Granular cell tumors of the tracheobronchial tree.

OBJECTIVE: To describe the population-based incidence and clinical characteristics of granular cell tumors of the tracheobronchial tree. METHODS: All newly registered tracheobronchial granular cell tumors in the Dutch Network and National Database for Pathology for 10 consecutive years (1990-1999) were identified. The histologic diagnosis was confirmed and patient demographics, management, and follow-up data were analyzed. RESULTS: Thirty-one tumors were registered in 30 patients (12 male patients and 18 female patients; mean age 51 years; range 11-84) in a population of approximately 15 million. Tracheal tumors were identified in 11 patients and bronchial tumors in 19 patients (1 patient had 2 tumors). About half of the patients were asymptomatic. In the majority of the patients (61%) the granular cell tumor was an incidental finding during workup for lung carcinoma. Tracheal granular cell tumors were more frequent in women, whereas bronchial granular cell tumors showed no sex predilection. In the lung these tumors occurred more often in the upper (10 tumors) than in the lower lobes (3 tumors). There was no preference for either side. Four patients with tracheal and 4 with bronchial granular cell tumors were treated with surgery and remain in complete remission. Four bronchial granular cell tumor patients were treated locally with neodymium/yttrium-aluminum-garnet laser or electrocautery and are in complete remission or have stable residual disease. In 3 patients no residual disease was found after biopsy. Of all granular cell tumor patients 17 received no treatment for a variety of reasons, but none of these patients died in the follow-up period because of the granular cell tumors. CONCLUSION: Tracheobronchial granular cell tumor is a benign tumor with a good prognosis. In symptomatic patients surgical intervention is the first choice of treatment, but local treatment is a reasonable option and gives successful results.

Adolescent↗
PubMed2003

Temozolomide in patients with advanced non-small cell lung cancer with and without brain metastases. a phase II study of the EORTC Lung Cancer Group (08965).

This study was performed to evaluate the activity of single-agent temozolomide in two groups of chemotherapy-naïve non-small cell lung cancer (NSCLC) patients, with (12 patients) and without (13 patients) brain metastases (BM). Patients in both groups were treated with temozolomide 200 mg/m(2)/day, administered orally for 5 consecutive days of a 28-day cycle. Treatment was continued for up to six cycles, disease progression or unacceptable toxicity. The median number of received cycles was only one in the group with and two in the group without BM, and early disease progression was the main reason for treatment discontinuation. Toxicity was moderate-in the group of patients with BM, the most frequently observed grade 3 or 4 side-effects included thrombocytopenia (17%), granulocytopenia (17%), lethargy (17%); other neurological (17%) and other genitourinary toxicity (17%). Patients without BM experienced anaemia (15%), thrombocytopenia (23%), nausea (15%) and lethargy (15%). This trial was designed according to Simon one-sample two-stage testing procedure and both groups of patients were assessed separately. No objective response was observed in either group and the study was closed after the first step of accrual with the conclusion of a lack of therapeutic activity of single-agent temozolomide in patients with stage IV NSCLC.

Adult↗
PubMed2003

Electrical impedance tomography to measure pulmonary perfusion: is the reproducibility high enough for clinical practice?

A possible clinical application of electrical impedance tomography (EIT) might be to monitor changes in the pulmonary circulation, provided the reproducibility of the EIT measurement is adequate. The purpose of this study was threefold: the intra- and inter-investigator variability of repeated measurements was investigated. Three different regions of interest (ROI) were analysed to assess the optimal ROI. Twenty-four healthy subjects and six patients were included. The Sheffield applied potential tomograph (DAS-01P, IBEES, Sheffield, UK) was used. Electrodes were attached by investigator A, and duplicate EIT measurements were performed. After detachment and 45 min of rest, the protocol was repeated by another investigator B, and afterwards by the initial investigator A. Three ROIs were analysed: whole circle, 'inner half circle' and contour. The mean difference in impedance changes between observers is presented in arbitrary units (AU) +/- SD. Finally, the influence of age, body composition and sex on the EIT result was examined. For the contour ROI, the mean difference for the intra-investigator situation was -1.44 x 10(-2) +/- 18.45 x 10(-2) AU (-0.7 +/- 9.0%), and was 5.46 x 10(-2) +/- 21.66 x 10(-2) AU (2.7 +/- 10.8%) for the inter-investigator situation. The coefficient of reproducibility of the intra- and inter-investigator reproducibility varied between 0.89 and 0.97 for all ROIs (P < 0.0001). There is a relation between impedance change and age (correlation coefficient r = -0.63, P < 0.01 for contour ROI), and between impedance change and body mass index (BMI) (r = -0.53, P < 0.05). We found a significant difference in mean impedance change between groups of males and females. In conclusion, EIT results are highly reproducible when performed by the same investigator as well as by two different investigators.

Adolescent↗
PubMed2003

Economic evaluation of antibiotic prophylaxis in small-cell lung cancer patients receiving chemotherapy: an EORTC double-blind placebo-controlled phase III study (08923).

BACKGROUND: To determine whether the cost of prophylactic antibiotics during chemotherapy is offset by cost savings due to a decreased incidence of febrile leukopenia (FL). PATIENTS AND METHODS: Small-cell lung cancer (SCLC) patients were randomised to standard or intensified chemotherapy with granulocyte colony-stimulating factor to assess the impact on survival (n = 244). In addition, patients were randomised to prophylactic ciprofloxacin and roxithromycin or placebo to assess the impact on FL (n = 161). The economic evaluation examined the costs and effects of patients taking antibiotics versus placebo. Medical resource utilisation was documented prospectively, including 33 patients from one centre in The Netherlands (NL) and 49 patients from one centre in Germany (GE). The evaluation takes the perspective of the health insurance systems and of the hospitals. Sensitivity analyses were performed. RESULTS: In the main trial, prophylactic antibiotics reduced the incidence of FL, hospitalisation due to FL and use of therapeutic antibiotics by 50%. In GE, the incidence of FL was not reduced by prophylaxis. This resulted in an average cost difference of only 35 Euros [95% confidence interval (CI) (-)1.713-2.263] in favour of prophylaxis (not significant). In NL, prophylaxis reduced the incidence of FL by nearly 50%, comparable with the results of the main trial, resulting in a cost difference of 2706 Euros [95% CI 810-5948], demonstrating savings in favour of prophylactic antibiotics of nearly 45%. Sensitivity analyses indicate that with an efficacy of prophylaxis of 50%, and with expected costs of antibiotic prophylaxis of 500 Euros or less, cost savings will incur over a broad range of baseline risks for FL; that is, a risk >10-20% for FL per cycle. CONCLUSIONS: Giving oral prophylactic antibiotics to SCLC patients undergoing chemotherapy is the dominant strategy in both GE and NL, demonstrating both cost-savings and superior efficacy. The sensitivity analyses demonstrate that, due to the efficacy of prophylactic antibiotics and their low unit cost, cost savings will incur over a broad range of baseline risks for FL. We recommend the use of prophylactic antibiotics in patients at risk for FL during chemotherapy.

Administration, Oral↗
PubMed2003

ALIMTA (pemetrexed disodium) as second-line treatment of non-small-cell lung cancer: a phase II study.

BACKGROUND: The purpose of this study was to evaluate ALIMTA (pemetrexed disodium, LY231514), a multi-targeted antifolate with first-line activity against non-small-cell lung cancer (NSCLC), in a second-line setting. PATIENTS AND METHODS: Patients with NSCLC were eligible for this phase II study if they had progressive disease within 3 months after first-line chemotherapy or progression while being treated with first-line chemotherapy. In 81 patients studied, two cohorts of patients were assigned based on whether the first-line therapy had included a platinum regimen. ALIMTA was administered at 500 mg/m2 by 10-min intravenous infusion once every 21 days. RESULTS: The response rate in the 79 evaluable patients with poor prognostic features was 8.9% [95% confidence interval (CI) 2.6% to 15.1%]. The response rate in the platinum-pretreated group was 4.5% and 14.1% in the non-platinum-pretreated group. The median duration of response was 6.8 months (95% CI 3.4-7.8 months, 0% censoring). The median survival time was 5.7 months (95% CI 4.0-8.3 months, 7.6% censoring). The probability of survival for at least 6 months was estimated to be 48%. The median time to disease progression was 2 months (95% CI 1.4-2.8 months, 0% censoring). The principal toxicity was myelosuppression, which was reversible. CONCLUSIONS: ALIMTA is active in a second-line setting in non-platinum-pretreated NSCLC patients progressing within 3 months of first-line chemotherapy. This study demonstrates that it is possible to evaluate new drugs against NSCLC in a second-line setting.

Adult↗
PubMed2003

Prospective use of serial questionnaires to evaluate the therapeutic efficacy of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in suspected lung cancer.

BACKGROUND: A study was undertaken to study the effect of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on the diagnosis and management of clinically problematic patients with suspected non-small cell lung cancer (NSCLC). METHODS: A prospective before-after study was performed in a cohort of all 164 patients (university/community settings) referred for PET between August 1997 and July 1999. PET was restricted to cases where non-invasive tests had failed to solve clinical problems. The impact on diagnostic understanding and management was assessed using questionnaires (intended treatment without PET, actual treatment choice after PET, post hoc clinical assessment). RESULTS: Diagnostic problems especially pertained to unclear radiological findings (n=112; 63%), mediastinal staging (n=36; 20%), and distant staging issues (n=16; 9%). PET findings were validated by reviewing medical records. PET had a positive influence on diagnostic understanding in 84%. Improved diagnostic understanding solely based on PET was reported in 26%. According to referring physicians, PET resulted in beneficial change of treatment in 50%. Cancelled surgery was the most frequent change in treatment after PET (35%). CONCLUSION: FDG PET applied as "add on" technology in patients with these clinical problems appears to be a clinically useful tool, directly improving treatment choice in 25% of patients. The value of increased confidence induced by PET scanning requires further evaluation.

Carcinoma, Non-Small-Cell Lung↗