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Journal RefereesRadiology
Publications (127) View all
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Article: Value of combined 6-[18F]fluorodihydroxyphenylalanine PET/CT for imaging of neuroendocrine tumours.
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ABSTRACT: Accurate knowledge of tumour presence and location is essential to treat neuroendocrine tumours (NETs). Standard imaging has been hampered by low sensitivity and lack of spatial resolution. This study assessed prospectively the diagnostic value and impact of combined 6-[18F]fluorodihydroxyphenylalanine positron emission tomography-computed tomography (18F-DOPA-PET/CT) in the management of NET. 18F-DOPA-PET/CT findings in 61 patients with suspected NET were compared with a composite reference standard including somatostatin receptor scintigraphy (SRS), magnetic resonance imaging, computed tomography, histological examination and clinical follow-up. The impact on clinical management was estimated by calculating the proportion of patients whose treatment changed as a result of 18F-DOPA-PET/CT findings. 18F-DOPA-PET/CT correctly identified 32 of 36 patients with NET. The sensitivity and specificity of 18F-DOPA-PET/CT for the detection of NET were 91 and 96 per cent respectively. Sensitivity using SRS was significantly lower (59 per cent), whereas the specificity was similar (86 per cent). In 16 (26 per cent) of the 61 patients the management was altered as a result of new findings on 18F-DOPA-PET/CT. 18F-DOPA-PET/CT yields a high sensitivity and specificity in the detection of NET. The clinical impact was highly relevant as changes in therapy were observed in more than a quarter of the patients.British Journal of Surgery 03/2010; 97(5):691-7. · 4.61 Impact Factor -
Article: Molecular imaging of malignant tumor metabolism: whole-body image fusion of DWI/CT vs. PET/CT.
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ABSTRACT: To prospectively investigate the technical feasibility and performance of image fusion for whole-body diffusion-weighted imaging (wbDWI) and computed tomography (CT) to detect metastases using hybrid positron emission tomography/computed tomography (PET/CT) as reference standard. Fifty-two patients (60 ± 14 years; 18 women) with different malignant tumor disease examined by PET/CT for clinical reasons consented to undergo additional wbDWI at 1.5 Tesla. WbDWI was performed using a diffusion-weighted single-shot echo-planar imaging during free breathing. Images at b = 0 s/mm(2) and b = 700 s/mm(2) were acquired and apparent diffusion coefficient (ADC) maps were generated. Image fusion of wbDWI and CT (from PET/CT scan) was performed yielding for wbDWI/CT fused image data. One radiologist rated the success of image fusion and diagnostic image quality. The presence or absence of metastases on wbDWI/CT fused images was evaluated together with the separate wbDWI and CT images by two different, independent radiologists blinded to results from PET/CT. Detection rate and positive predictive values for diagnosing metastases was calculated. PET/CT examinations were used as reference standard. PET/CT identified 305 malignant lesions in 39 of 52 (75%) patients. WbDWI/CT image fusion was technically successful and yielded diagnostic image quality in 73% and 92% of patients, respectively. Interobserver agreement for the evaluation of wbDWI/CT images was κ = 0.78. WbDWI/CT identified 270 metastases in 43 of 52 (83%) patients. Overall detection rate and positive predictive value of wbDWI/CT was 89% (95% CI, 0.85-0.92) and 94% (95% CI, 0.92-0.97), respectively. WbDWI/CT image fusion is technically feasible in a clinical setting and allows the diagnostic assessment of metastatic tumor disease detecting nine of 10 lesions as compared with PET/CT.Academic radiology 08/2011; 18(8):940-6. · 2.09 Impact Factor -
Article: Diagnostic accuracy of whole-body MRI/DWI image fusion for detection of malignant tumours: a comparison with PET/CT.
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ABSTRACT: To prospectively evaluate the diagnostic accuracy of whole-body T2-weighted (wbT2), whole-body diffusion-weighted imaging (wbDWI) and wbT2/wbDWI image fusion for malignant tumour detection compared with PET/CT. Sixty-eight patients (44 men; 60 ± 14 years) underwent PET/CT for staging of malignancy and were consecutively examined by 1.5-Tesla MRI including wbT2 and wbDWI. Two radiologists independently assessed wbDWI, wbT2, wbT2 + wbDWI (side-by-side) and wbT2 + wbDWI + wbT2/wbDWI image fusion for the presence of malignancy. PET/CT served as a reference standard. PET/CT revealed 374 malignant lesions in 48/64 (75%) patients. Detection rates and positive predictive value (PPV) of wbT2 and wbDWI alone were 64% and 84%, and 57% and 93%, respectively. Detection rates and PPV of wbT2 and wbDWI for side-by-side analysis without and with fused images were 72% and 89%, and 74% and 91%, respectively. The detection rate was significantly higher with side-by-side analysis and fused image analysis compared with wbT2 and wbDWI alone (p = .0159; p < .0001). There was no significant difference between fused image interpretation and side-by-side analysis. WbDWI allows detection of malignant lesions with a similar detection rate to wbT2. Side-by-side analysis of wbT2 and wbDWI significantly improves the overall detection rate and fused image data provides no added value.European Radiology 02/2011; 21(2):246-55. · 3.22 Impact Factor -
Article: Limited predictive value of FDG-PET for response assessment in the preoperative treatment of esophageal cancer: results of a prospective multi-center trial (SAKK 75/02).
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ABSTRACT: Only responding patients benefit from preoperative therapy for locally advanced esophageal carcinoma. Early detection of non-responders may avoid futile treatment and delayed surgery. In a multi-center phase ll trial, patients with resectable, locally advanced esophageal carcinoma were treated with 2 cycles of induction chemotherapy followed by chemoradiotherapy (CRT) and surgery. Positron emission tomography with 2[fluorine-18]fluoro-2-deoxy-d-glucose (FDG-PET) was performed at baseline and after induction chemotherapy. The metabolic response was correlated with tumor regression grade (TRG). A decrease in FDG tumor uptake of less than 40% was prospectively hypothesized as a predictor for histopathological non-response (TRG > 2) after CRT. 45 patients were included. The median decrease in FDG tumor uptake after chemotherapy correlated well with TRG after completion of CRT (p = 0.021). For an individual patient, less than 40% decrease in FDG tumor uptake after induction chemotherapy predicted histopathological non-response after completion of CRT, with a sensitivity of 68% and a specificity of 52% (positive predictive value 58%, negative predictive value 63%). Metabolic response correlated with histopathology after preoperative therapy. However, FDG-PET did not predict non-response after induction chemotherapy with sufficient clinical accuracy to justify withdrawal of subsequent CRT and selection of patients to proceed directly to surgery.Onkologie 01/2009; 32(12):724-30. · 0.87 Impact Factor -
Article: Clinical impact of 18F-choline PET/CT in patients with recurrent prostate cancer.
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ABSTRACT: To investigate the clinical value of (18)F-fluorocholine PET/CT (CH-PET/CT) in treatment decisions in patients with recurrent prostate cancer (rPCA). The study was a retrospective evaluation of 156 patients with rPCA and CH-PET/CT for restaging. Questionnaires for each examination were sent to the referring physicians 14-64 months after examination. Questions included information regarding initial extent of disease, curative first-line treatment, and the treatment plan before and after CH-PET/CT. Additionally, PSA values at diagnosis, after initial treatment, before CH-PET/CT and at the end of follow-up were also obtained from the questionnaires. Mean follow-up was 42 months. The mean Gleason score was 6.9 at initial diagnosis. Initial treatment was: radical prostatectomy in 110 patients, radiotherapy in 39, and combined prostatectomy and radiotherapy in 7. Median PSA values before CH-PET/CT and at the end of follow-up were 3.40 ng/ml and 0.91 ng/ml. PSA levels remained stable, decreased or were below measurable levels in 108 patients. PSA levels increased in 48 patients. In 75 of the 156 patients (48%) the treatment plan was changed due to the CH-PET/CT findings. In 33 patients the therapeutic plan was changed from palliative treatment to treatment with curative intent. In 15 patients treatment was changed from curative to palliative. In 8 patients treatment was changed from curative to another strategy and in 2 patients from one palliative strategy to another. In 17 patients the treatment plan was adapted. CH-PET/CT has an important impact on the therapeutic strategy in patients with rPCA and can help to determine an appropriate treatment.European Journal of Nuclear Medicine 03/2012; 39(6):936-43. · 4.53 Impact Factor
