Magnetic resonance imaging of induration in the irradiated breast.

Background: The causes of induration (hardness) in the breast many years after tumour excision and whole breast radiotherapy for early stage breast cancer are not well established. The purpose of this study is to describe morphological magnetic resonance imaging (MRI) appearances and MRI-derived microvascular functional characteristics of the indurated breast several years post-treatment.

Patients And Methods: Fifteen women with moderate or marked induration at the electron boost site after breast preserving surgery and radiotherapy for early breast cancer (median 6 years; range, 2-15 years) underwent MRI, including 6/15 with very marked breast shrinkage and 8/15 with marked induration.

Effects of 5,6-dimethylxanthenone-4-acetic acid on human tumor microcirculation assessed by dynamic contrast-enhanced magnetic resonance imaging.

Purpose: 5,6-Dimethylxanthenone-4-acetic acid (DMXAA) causes vascular shutdown in preclinical models. Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) studies were performed in the phase I trials to examine changes related to blood flow and permeability in tumor and muscle.

Patients And Methods: Sixteen patients treated with DMXAA from 500 to 4,900 mg/m(2) had DCE-MRI examinations before and after treatment.

Diffusion MRI for prediction of response of rectal cancer to chemoradiation.

Prediction of tumour response before onset of treatment could have considerable clinical benefit. Since the apparent diffusion coefficient (ADC) of a tumour's water content can show the extent of necrosis, we looked for a possible correlation of ADC with response to treatment. We measured mean tumour water ADC before and after chemotherapy and chemoradiation in 14 patients with locally advanced rectal cancer, with a quantitative magnetic resonance diffusion imaging sequence.

Assessing changes in tumour vascular function using dynamic contrast-enhanced magnetic resonance imaging.

Dynamic contrast-enhanced MRI (DCE-MRI) is widely used in the diagnosis and staging of cancer and is emerging as a promising method for monitoring tumour response to treatment. However, DCE-MR imaging techniques are still evolving and methods of image analysis remain variable and non-standard, and range from relative changes in the pattern of enhancement to pharmacokinetic modelling of contrast agent uptake. The combination of results from different institutions is therefore difficult and the sensitivities of different methods have not been compared.

Reproducibility of quantitative dynamic MRI of normal human tissues.

The aim of the study was to establish the normal range and to evaluate the reproducibility of dynamic contrast enhanced MRI (DCE-MRI) parameter estimates in normal human pelvic tissues. Nineteen patients with prostate cancer, undergoing androgen deprivation treatment, had paired DCE-MRI examinations of the pelvis using spoiled gradient-echo sequences. Quantitative enhancement parameters were calculated for each examination: transfer constant (K(trans)), leakage space (v(e)) and maximum contrast medium accumulation (MCMA) of pelvic muscles, bone marrow and fat.

Reproducibility of dynamic contrast-enhanced MRI in human muscle and tumours: comparison of quantitative and semi-quantitative analysis.

The purpose of this study was to determine the reproducibility of dynamic contrast-enhanced (DCE)-MRI and compare quantitative kinetic parameters with semi-quantitative methods, and whole region-of-interest (ROI) with pixel analysis. Twenty-one patients with a range of tumour types underwent paired MRI examinations within a week, of which 16 pairs were evaluable. A proton density-weighted image was obtained prior to a dynamic series of 30 T(1)-weighted spoiled gradient echo images every 11.