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Gabriel Snoep

Publications and source records attributed to Gabriel Snoep.

10 recordsLinked to original sources
PubMed2006

Omission of elective node irradiation on basis of CT-scans in patients with limited disease small cell lung cancer: a phase II trial.

PURPOSE: To evaluate the patterns of recurrence when elective node irradiation was omitted in patients with limited disease small cell lung cancer (LD-SCLC). METHODS: A prospective phase II study was undertaken in 27 patients with LD-SCLC without detectable distant metastases on CT scan. Chest radiotherapy to a dose of 45 Gy in 30 fractions in 3 weeks (1.5 Gy BID with 6 - 8 h interval) was delivered concurrently with carboplatin and etoposide chemotherapy. Chest radiation started after a mean time of 17.7 days +/- 9.7 days (SD) (range: 0-33 days) after the beginning of chemotherapy. Only the primary tumour and the positive nodal areas on the pre-treatment CT scan were irradiated. A total of five chemotherapy cycles were administered, followed by prophylactic cranial irradiation (PCI) in patients without disease progression. Isolated nodal failure was defined as recurrence in the regional nodes outside of the clinical target volume, in the absence of in-field failure. RESULTS: After a median time of 18 months post-radiotherapy, 7 patients (26%, 95% CI 19.5-42.5%) developed a local recurrence. Three patients (crude rate 11%, 95% CI 2.4-29%), developed an isolated nodal failure, all of them in the ipsilateral supraclavicular fossa. The median actuarial overall survival was 21 months (95% CI 15.3-26.7), and the median actuarial progression free survival was 16 months (95% CI 6.5-25.5). Eight patients developed an acute, reversible grade 3 (CTC 3.0) radiation oesophagitis (30%, 95% CI 14-50%). CONCLUSIONS: Because of the small sample size, no definitive conclusions can be drawn. However, the omission of elective nodal irradiation on the basis of CT scans in patients with LD-SCLC resulted in a higher than expected rate of isolated nodal failures in the ipsilateral supraclavicular fossa. The incidence of acute, reversible oesophagitis was in the same range as reported with elective nodal fields. The safety of selective nodal irradiation in NSCLC should not be extrapolated to patients with LD-SCLC until more data are available. In the mean time, elective nodal irradiation should only be omitted in clinical trials.

Aged↗
PubMed2005

Selective mediastinal node irradiation based on FDG-PET scan data in patients with non-small-cell lung cancer: a prospective clinical study.

PURPOSE: To evaluate the patterns of recurrence when selective mediastinal node irradiation based on FDG-PET scan data is used in patients with non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: A prospective Phase I/II study was undertaken on 44 patients with NSCLC without detectable distant metastases on CT and FDG-PET scan, delivering either 61.2 Gy in 34 fractions over 23 days or 64.8 Gy in 36 fractions over 24 days (1.8 Gy b.i.d. with 8-h interval). Only the primary tumor and the positive mediastinal areas on the pretreatment FDG-PET scan were irradiated. Isolated nodal failure was defined as recurrence in the regional nodes outside of the clinical target volume, in the absence of in-field failure. RESULTS: The CT and FDG-PET stage distribution was as follows: Stage I: 8 patients (18%) and 13 patients (29%); Stage II: 6 patients (14%) and 10 patients (23%); Stage IIIA: 15 patients (34%) and 7 patients (16%); Stage IIIB: 15 patients (34%) and 14 patients (32%), respectively. After a median follow-up time of 16 months (95% confidence interval [CI], 11-21 months) postradiotherapy, 11 patients (25%) developed a local recurrence. Only 1 patient (crude rate, 2.3%; upper bound of 95% CI, 10.3%), with a Stage II tumor on both CT and PET, developed an isolated nodal failure. The median actuarial overall survival was 21 months (95% CI, 14-28 months), and the median actuarial progression-free survival was 18 months (95% CI, 12-24 months). CONCLUSIONS: Selective mediastinal node irradiation based on FDG-PET scan data in patients with NSCLC results in low isolated nodal failure rates. In the Phase I component of this trial, radiation dose escalation up to 64.8 Gy in 36 fractions over 24 days is feasible.

Aged↗
PubMed2005

Effects of radiotherapy planning with a dedicated combined PET-CT-simulator of patients with non-small cell lung cancer on dose limiting normal tissues and radiation dose-escalation: a planning study.

BACKGROUND AND PURPOSE: To investigate the effect of radiotherapy planning with a dedicated combined PET-CT simulator of patients with locally advanced non-small cell lung cancer. PATIENTS AND METHODS: Twenty-one patients underwent a pre-treatment simulation on a dedicated hybrid PET-CT-simulator. For each patient, two 3D conformal treatment plans were made: one with a CT based PTV and one with a PET-CT based PTV, both to deliver 60Gy in 30 fractions. The maximum tolerable prescribed radiation dose for CT versus PET-CT PTV was calculated based on constraints for the lung, the oesophagus, and the spinal cord, and the Tumour Control Probability (TCP) was estimated. RESULTS: For the same toxicity levels of the lung, oesophagus and spinal cord, the dose could be increased from 55.2+/-2.0Gy with CT planning to 68.9+/-3.3Gy with the use of PET-CT (P=0.002), with corresponding TCP's of 6.3+/-1.5% for CT and 24.0+/-5.6% for PET-CT planning (P=0.01). CONCLUSIONS: The use of a combined dedicated PET-CT-simulator reduced radiation exposure of the oesophagus and the lung, and thus allowed significant radiation dose escalation whilst respecting all relevant normal tissue constraints.

Carcinoma, Non-Small-Cell Lung↗
PubMed2005

Evaluation of the accuracy of gadolinium-enhanced cardiovascular magnetic resonance in the diagnosis of cardiac sarcoidosis.

OBJECTIVES: This study analyzed the accuracy of gadolinium-enhanced cardiovascular magnetic resonance (CMR) for the diagnosis of cardiac sarcoidosis (CS). BACKGROUND: The diagnosis of CS was made according to the guidelines of the Japanese Ministry of Health and Welfare (1993); CMR has not been incorporated into the guidelines, and the diagnostic accuracy of CMR for the diagnosis of CS has not yet been evaluated. METHODS: We performed an analysis of 12-lead electrocardiograms (ECGs), 24-h ambulatory ECGs, echocardiograms, thallium scintigrams, and gadolinium-enhanced CMR studies in 58 biopsy-proven pulmonary sarcoidosis patients assessed for CS. The diagnostic accuracy of CMR for CS was determined using modified Japanese guidelines as the gold standard. RESULTS: The diagnosis of CS was made in 12 of 58 patients (21%); CMR revealed late gadolinium enhancement (LGE), mostly involving basal and lateral segments (73%), in 19 patients. In 8 of the 19 patients, scintigraphy was normal, while patchy LGE was present. The sensitivity and specificity of CMR were 100% (95% confidence interval, 78% to 100%) and 78% (95% confidence interval, 64% to 89%), and the positive and negative predictive values were 55% and 100%, respectively, with an overall accuracy of 83%. CONCLUSIONS: In patients with sarcoidosis, CMR is a useful diagnostic tool to determine cardiac involvement. New diagnostic guidelines should include CMR.

Adult↗
PubMed2005

Cardiac involvement in patients with pulmonary sarcoidosis assessed at two university medical centers in the Netherlands.

STUDY OBJECTIVES: We aimed to determine cardiac involvement in patients with pulmonary sarcoidosis (PS) followed up at two university medical centers in the Netherlands. DESIGN: We reviewed the findings in consecutive patients assessed by our departments during 1998 to 2004, and classified them as patients who had presented with symptoms of cardiac sarcoidosis (CS) [group A], and those who had been screened for this condition (group B). SETTING: Two university medical centers in the Netherlands. PATIENTS: One hundred one patients (69 men [mean age, 47.6 years] and 32 women [mean age, 47.3 years]) with biopsy-proven PS. INTERVENTIONS: Twelve-lead ECG (n = 101), ambulatory ECG (n = 74), echocardiography (n = 80), (201)Tl single-photon emission CT (n = 61), cardiac MRI (n = 87), coronary angiography to exclude coronary artery disease (n = 17), and endomyocardial biopsy (n = 9). MEASUREMENTS: ECG, structural, and functional cardiac abnormalities according to the modified guidelines of the Japanese Ministry of Health and Welfare (1993). RESULTS: Sixteen of 19 patients in group A and 3 of 82 patients in group B received a diagnosis of CS. During a mean follow-up of 1.7 years (range, 3 months to 4 years), four patients in group A died (20%) and nine patients received a pacemaker and/or an implantable cardioverter-defibrillator (47%), while the patients in group B had an uncomplicated course. CONCLUSIONS: Once symptomatic CS develops in PS patients, the prognosis becomes very grim. In contrast, the prognosis in asymptomatic cardiac involvement in PS patients is good. Considering the poor prognosis of symptomatic CS, pulmonologists should consider regular screening of their PS patients for cardiac involvement with straightforward detection methods.

Adult↗
PubMed2005

The additional value of gadolinium-enhanced MRI to standard assessment for cardiac involvement in patients with pulmonary sarcoidosis.

AIM: To determine whether gadolinium-enhanced cardiac MRI (CMR) was of additional diagnostic value to standard assessment in patients with sarcoidosis who underwent evaluation for cardiac involvement. METHODS: We reviewed the findings in patients with pulmonary sarcoidosis who had been assessed with ECG, Doppler echocardiography, 201Tl scintigraphy, and CMR from 2002 to 2004. RESULTS: Of the 55 evaluated patients, standard evaluation diagnosed cardiac involvement in 13 patients while CMR diagnosed myocardial scarring (mean +/- SD, 2.5 +/- 1.9 segments) [all 6 patients] and impaired systolic left ventricular function (1 patient) in an additional 6 patients. The extent of delayed enhancement correlated with disease duration (p < 0.05), ventricular dimensions and function (p < 0.001), severity of mitral regurgitation (p < 0.05), and the presence of ventricular tachycardias (p < 0.001). Patients in whom cardiac involvement was diagnosed only with CMR had less myocardial scarring and functional impairment (p < 0.05) compared to patients with a diagnosis made by standard assessment. CONCLUSION: CMR provides an accurate estimation of the extent of cardiac involvement and may reveal signs of early infiltration that are not detected by standard assessment. The extent of late enhancement with gadolinium relates to the severity of cardiac involvement and may therefore have prognostic implications.

Diagnostic Techniques, Cardiovascular↗
PubMed2004

Tropical endomyocardial fibrosis (Davies' disease): case report demonstrating the role of magnetic resonance imaging.

Tropical endomyocardial fibrosis (TEMF), a restrictive cardiomyopathy of unclear etiology, is an endemic disease in equatorial Africa, South America and India. The patients are usually young, the onset of the disease and its clinical manifestations insidious, and the prognosis poor. We currently present a 50-year-old Congolese female who was referred with symptoms of progressive right-sided heart failure due to isolated TEMF of the right ventricle. Surgical resection of regional endomyocardial fibrosis was not possible and our patient was referred for cardiac transplantation. Cardiac magnetic resonance imaging (CMR) demonstrated the primary and secondary structural and functional abnormalities. CMR seems ideally suited to diagnose this condition and monitor response to medical and/or surgical therapy.

Cardiac Output, Low↗