Publications by authors named "P S Ryymin"

Background: Colorectal cancer liver metastases respond to chemotherapy and targeted agents not only by shrinking, but also by morphologic and metabolic changes. The aim of this study was to evaluate the value of advanced magnetic resonance imaging (MRI) methods in predicting treatment response and survival.

Patients And Methods: We investigated contrast-enhanced MRI, apparent diffusion coefficient (ADC) in diffusion-weighted imaging and H-magnetic resonance spectroscopy (H-MRS) in detecting early morphologic and metabolic changes in borderline or resectable liver metastases, as a response to first-line neoadjuvant or conversion therapy in a prospective substudy of the RAXO trial (NCT01531621, EudraCT2011-003158-24).

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Purpose: To evaluate the utility of multi-parametric magnetic resonance imaging (MP-MRI), including dynamic contrast-enhanced MRI and diffusion-weighted MRI, for monitoring tumor tissue changes after volumetric-modulated arc radiotherapy in localized prostate cancer (PCa), and to compare the radiotherapy induced tumor tissue changes between conventional, moderate and extreme hypofractionated groups. Furthermore, we aimed to evaluate if follow-up by MRI has an incremental value compared to the standard care by prostate-specific antigen (PSA) serum level measurement.

Materials And Methods: Fifty-five men (mean age: 70±5 [SD] years; range: 60-79 years) with biopsy-proven PCa underwent MRI examination before radiotherapy, and at 3 and 12 months after radiotherapy.

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Background And Purpose: Although several methods have been developed to predict the outcome of patients with prostate cancer, early diagnosis of individual patient remains challenging. The aim of the present study was to correlate tumor perfusion parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and clinical prognostic factors and further to explore the diagnostic value of DCE-MRI parameters in early stage prostate cancer.

Patients And Methods: Sixty-two newly diagnosed patients with histologically proven prostate adenocarcinoma were enrolled in our prospective study.

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Background: Diffusion-weighted imaging (DWI) with measurement of apparent diffusion coefficient (ADC) allows for assessment of tumor aggressiveness. The objective of this study was to evaluate the changes of ADC value in prostate cancer after volumetric-modulated arc radiotherapy (VMAT) and to identify magnetic resonance imaging (MRI) biomarkers for monitoring tissue changes after radiotherapy.

Patients And Methods: Thirty-seven patients with biopsy-proven prostate cancer treated with VMAT underwent serial MRI examinations including DWI before radiotherapy, and at 3 and 12 months after radiotherapy.

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Objectives: To investigate whether diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) correlates with prostate cancer aggressiveness and further to compare the diagnostic performance of ADC and normalized ADC (nADC: normalized to non-tumor tissue).

Patients And Methods: Thirty pre-treatment patients (mean age, 69years; range: 59-78years) with prostate cancer underwent magnetic resonance imaging (MRI) examination, including DWI with three b values: 50, 400, and 800s/mm. Both ADC and nADC were correlated with the Gleason score obtained through transrectal ultrasound-guided biopsy.

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