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Since the introduction, pelvic MRI has been considered the best non-invasive technique for primary staging of urinary bladder cancer. Before using MRI an understanding of normal and pathological MR images of the urinary bladder is essential. This review therefore describes the MR anatomy of the urinary bladder as well as the appearances of carcinoma. MRI plays an important clinical role in staging the primary tumour. In superficial tumours, clinical staging, which includes transurethral biopsy, is the best technique. For invasive tumours, MRI is superior to other techniques such as CT scanning, transvesical ultrasonography and clinical staging. A limitation of both MRI and CT scanning is their inability to recognize minimal tumour growth in the muscle layer of the bladder wall, or to differentiate between post-transurethral resection oedema and tumour. Therefore, in all patients with urinary bladder cancer staging should preferably start with MRI followed by clinical staging. Unfortunately, however, because of the high cost of this strategy, MRI has to be reserved for staging deeply invasive and superficial poorly differentiated tumours. [ABSTRACT FROM AUTHOR]

In this paper, a fully automatic computer-aided detection (CAD) method is proposed for the detection of prostate cancer. The CAD method consists of multiple sequential steps in order to detect locations that are suspicious for prostate cancer. In the initial stage, a voxel classification is performed using a Hessian-based blob detection algorithm at multiple scales on an apparent diffusion coefficient map. Next, a parametricmulti-object segmentationmethod is applied and the resulting segmentation is used as a mask to restrict the candidate detection to the prostate. The remaining candidates are characterized by performing histogram analysis on multiparametricMRimages. The resulting feature set is summarized into amalignancy likelihood by a supervised classifier in a two-stage classification approach. The detection performance for prostate cancer was tested on a screening population of 200 consecutive patients and evaluated using the free response operating characteristic methodology. The results show that the CAD method obtained sensitivities of 0.41, 0.65 and 0.74 at false positive (FP) levels of 1, 3 and 5 per patient, respectively. In conclusion, this study showed that it is feasible to automatically detect prostate cancer at a FP rate lower than systematic biopsy. The CAD method may assist the radiologist to detect prostate cancer locations and could potentially guide biopsy towards the most aggressive part of the tumour. [ABSTRACT FROM AUTHOR]

Purpose: Computer aided diagnosis (CAD) of lymph node metastases may help reduce reading time and improve interpretation of the large amount of image data in a 3-D pelvic MRI exam. The purpose of this study was to develop an algorithm for automated segmentation of pelvic lymph nodes from a single seed point, as part of a CAD system for the classification of normal vs metastatic lymph nodes, and to evaluate its performance compared to other algorithms. Methods: The authors' database consisted of pelvic MR images of 146 consecutive patients, acquired between January 2008 and April 2010. Each dataset included four different MR sequences, acquired after infusion of a lymph node specific contrast medium based on ultrasmall superparamagnetic particles of iron oxide. All data sets were analyzed by two expert readers who, reading in consensus, annotated and manually segmented the lymph nodes. The authors compared four segmentation algorithms: confidence connected region growing (CCRG), extended CCRG (ECC), graph cut segmentation (GCS), and a segmentation method based on a parametric shape and appearance model (PSAM). The methods were ranked based on spatial overlap with the manual segmentations, and based on diagnostic accuracy in a CAD system, with the experts' annotations as reference standard. Results: A total of 2347 manually annotated lymph nodes were included in the analysis, of which 566 contained a metastasis. The mean spatial overlap (Dice similarity coefficient) was: 0.35 (CCRG), 0.57 (ECC), 0.44 (GCS), and 0.46 (PSAM). When combined with the classification system, the area under the ROC curve was: 0.805 (CCRG), 0.890 (ECC), 0.807 (GCS), 0.891 (PSAM), and 0.935 (manual segmentation). Conclusions: We identified two segmentation methods, ECC and PSAM, that achieve a high diagnostic accuracy when used in conjunction with a CAD system for classification of normal vs metastatic lymph nodes. The manual segmentations still achieve the highest diagnostic accuracy. [ABSTRACT FROM AUTHOR]

AbstractPurpose:To establish a consensus in relation to case selection, conduct of therapy, and outcomes that are associated with focal therapy for men with localized prostate cancer.Material and Methods:Urologic surgeons, radiation oncologists, radiologists, and histopathologists from North America and Europe participated in a consensus workshop on focal therapy for prostate cancer. The consensus process was face to face within a structured meeting, in which pertinent clinical issues were raised, discussed, and agreement sought. Where no agreement was possible, this was acknowledged, and the nature of the disagreement noted.Results:Candidates for focal treatment should have unilateral low- to intermediate-risk disease with clinical stage ≤cT2a. Prostate size and both tumor volume and tumor topography are important case selection criteria that depend on the ablative technology used. Currently, the best method to ascertain the key characteristics for men who are considering focal therapy is exposure to transperineal template mapping biopsies. MRI of the prostate using novel techniques such as dynamic contrast enhancement and diffusion weighed imaging are increasingly being used to diagnose and stage primary prostate cancer with excellent results. For general use, however, these new techniques require validation in prospective clinical trials. Until such are performed, MRI will, in most centers, continue to be an investigative tool in assessing eligibility of patients for focal therapy.Conclusions:Consensus was derived for most of the key aspects of case selection, conduct of treatment, and outcome measures for men who are undergoing focal therapy for localized prostate cancer. The level of agreement achieved will pave the way for future collaborative trials. [ABSTRACT FROM AUTHOR]

The purpose of this study was to define guidelines for endometrial cancer staging with MRI. The technique included critical review and expert consensus of MRI protocols by the female imaging subcommittee of the European Society of Urogenital Radiology, from ten European institutions, and published literature between 1999 and 2008. The results indicated that high field MRI should include at least two T2-weighted sequences in sagittal, axial oblique or coronal oblique orientation (short and long axis of the uterine body) of the pelvic content. High-resolution post-contrast images acquired at 2 min +/- 30 s after intravenous contrast injection are suggested to be optimal for the diagnosis of myometrial invasion. If cervical invasion is suspected, additional slice orientation perpendicular to the axis of the endocervical channel is recommended. Due to the limited sensitivity of MRI to detect lymph node metastasis without lymph node-specific contrast agents, retroperitoneal lymph node screening with pre-contrast sequences up to the level of the kidneys is optional. The likelihood of lymph node invasion and the need for staging lymphadenectomy are also indicated by high-grade histology at endometrial tissue sampling and by deep myometrial or cervical invasion detected by MRI. In conclusion, expert consensus and literature review lead to an optimized MRI protocol to stage endometrial cancer. [ABSTRACT FROM AUTHOR]

As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. Magnetic resonance imaging (MRI) may enhance the staging of prostate cancer compared with clinical evaluation, transrectal ultrasound, or computed tomography (CT), and allows concurrent evaluation of prostatic, periprostatic, and pelvic anatomy. In clinical practice, the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with MR spectroscopic imaging (MRSI) is improving the evaluation of cancer location, size, and extent, while providing an indication of tumor aggressiveness. Pretreatment knowledge of these prognostic variables is essential for achieving minimally invasive, patient-specific therapy. [ABSTRACT FROM AUTHOR]

Systemic chemotherapy is effective in only a subset of patients with metastasized colorectal cancer. Therefore, early selection of patients who are most likely to benefit from chemotherapy is desirable. Response to treatment may be determined by the delivery of the drug to the tumor, retention of the drug in the tumor and by the amount of intracellular uptake, metabolic activation and catabolism, as well as other factors. The first aim of this study was to investigate the predictive value of DCE-MRI with the contrast agent Gd-DTPA for tumor response to first-line chemotherapy in patients with liver metastases of colorectal cancer. The second aim was to investigate the predictive value of 5-fluorouracil (FU) uptake, retention and catabolism as measured by localized 19F MRS for tumor response to FU therapy. Since FU uptake, retention and metabolism may depend on tumor vascularization, the relationship between 19F MRS and the DCE-MRI parameters kep, Ktrans and ve was also examined (). In this study, 37 patients were included. The kinetic parameters of DCE-MRI, kep, Ktrans and ve, before start of treatment did not predict tumor response after 2 months, suggesting that the delivery of chemotherapy by tumor vasculature is not a major factor determining response in first-line treatment. No evident correlations between 19F MRS parameters and tumor response were found. This suggests that in liver metastases that are not selected on the basis of their tumor diameter, FU uptake and catabolism are not limiting factors for response. The transfer constant Ktrans, as measured by DCE-MRI before start of treatment, was negatively correlated with FU half-life in the liver metastases, which suggests that, in metastases with a larger tumor blood flow or permeability surface area product, FU is rapidly washed out from the tumor. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effectiveness of radioiodine therapy as an alternative for surgery in elderly patients with a large, compressive goiter using objective methods for measuring thyroid volume and tracheal compression.Design: Prospective study.Setting: University hospital in the Netherlands.Patients: 19 patients (mean age +/- SD, 66 +/- 14 years) with a large, compressive multinodular goiter who had a high operative risk or refused to have thyroid surgery.Intervention: A single intravenous dose of 131I at 2.6 +/- 1.0 GBq (70 +/- 28 mCi) (3.7 MBq or 100 microCi/g of thyroid tissue), followed by daily administration of L-thyroxine in doses that did not suppress thyroid-stimulating hormone.Measurements: Clinical evaluation and measurements of thyroid volume, maximal tracheal deviation, and the smallest cross-sectional area of the tracheal lumen with magnetic resonance imaging before and 1 year after 131I treatment.Results: No exacerbation of compressive symptoms after 131I therapy was observed. Thyroid volume was 269 +/- 153 mL before treatment and 154 +/- 73 mL 1 year after treatment (P < 0.001). Thyroid volume was reduced 40% +/- 15% (range, 19% to 68%). Maximal tracheal deviation (1.9 +/- 0.8 cm before and 1.5 +/- 0.7 cm 1 year after therapy) had decreased by 20% +/- 20% (range, -4% to 73%; P < 0.001), and the smallest cross-sectional area of tracheal lumen (0.78 +/- 0.38 cm2 before and 1.04 +/- 0.48 cm2 1 year after therapy) had increased by 36% +/- 38% (range, -3% to 125%; P < 0.001). Clinical signs and symptoms improved in 8 of 12 patients with dyspnea and inspiratory stridor and in both patients with compression of the superior vena cava.Conclusions: Therapy with 131I is an effective alternative to surgery for elderly patients with a large, compressive multinodular goiter. [ABSTRACT FROM AUTHOR]

A 67-year-old man was treated with maintenance intravesical BCG for superficial bladder cancer. As a culture-proven complication of this therapy, he developed general malaise, high fever, granulomatous hepatitis and a mycotic aneurysm in his left knee. All complications were treated successfully with antituberculous therapy. No vascular surgery was necessary. This case report again stresses the necessity to recognise complications of BCG treatment and to start adequate therapy as soon as possible.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A malignant fibrous histiocytoma of the mediastinum was successfully treated by surgery and radiotherapy. Magnetic resonance imaging was able to show the site of invasion, the two different components of the tumour, and the blood supply. [ABSTRACT FROM PUBLISHER]