Sadhna Verma

Assessment of Aggressiveness of Prostate Cancer: Correlation of Apparent Diffusion Coefficient With Histologic Grade After Radical Prostatectomy

OBJECTIVE The purpose of this article is to evaluate the relationship between apparent diffusion coefficient (ADC) values, tumor volume, and total Gleason grade in patients with prostate cancer before radical prostatectomy. MATERIALS AND METHODS A total of 110 patients with prostate cancer who had undergone endorectal prostate MRI at 1.5 T before radical prostatectomy were included. ADC values were derived by drawing a region of interest on the histologically confirmed tumors. Tumor volume was obtained by manual segmentation on T2-weighted images (T2WIs) and ADC maps. The relationship between the ADC value or tumor volume and the Gleason grade was assessed by using multivariate mixed linear and effect models. Multivariate analysis was performed to evaluate the accuracy of ADC and tumor volume in determining the aggressiveness of prostate cancer. RESULTS A total of 197 tumors were studied; 128 (65%) tumors were found in the peripheral zone and 69 (35%) were found in the central gland. The ADC value was found to be negatively correlated with the Gleason grade (r = -0.39 for peripheral zone cancer). Higher ADC values were found to be associated with lower Gleason grades in the peripheral zone prostate cancers. No association was found in the central zone prostate cancers. Both ADC values and tumor volumes were found to significantly predict tumor aggressiveness, specifically in the peripheral zone (area under the curve, 0.78). CONCLUSION ADC values were found to be negatively correlated with the postsurgical Gleason grade in patients with prostate cancer. Our results show that ADC values might help to predict prostate cancer, especially for tumors in the peripheral zone. Given the substantial overlap in the ADC values, the addition of other MR parameters, such as volumetry, and technical improvements in diffusion-weighted imaging might improve accuracy in the stratification of patients.

Synopsis of the PI-RADS v2 Guidelines for Multiparametric Prostate Magnetic Resonance Imaging and Recommendations for Use

Department of Radiology and Nuclear Medicine Radboudumc, Nijmegen, The Netherlands; Yale School of Medicine, New Haven, CT, USA; University of Cincinnati, Cincinnati, OH, USA; Harvard University, Boston, MA, USA; University Hospital of Bern, Bern, Switzerland; AdMeTech Foundation, Boston, MA, USA; g Paul Strickland Scanner Centre, Mount Vernon Hospital, Northwood, Middlesex, UK; University of California, Los Angeles, CA, USA; i Johns Hopkins University, Baltimore, MD, USA; University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Canada; Rene Descartes University, Paris, France; National Institutes of Health, Bethesda, MD, USA

Overview of Dynamic Contrast-Enhanced MRI in Prostate Cancer Diagnosis and Management

OBJECTIVE This article is a primer on the technical aspects of performing a high-quality dynamic contrast-enhanced MRI (DCE-MRI) examination of the prostate gland. CONCLUSION DCE-MRI is emerging as a useful clinical technique as part of a multi-parametric approach for evaluating the extent of primary and recurrent prostate cancer. Performing a high-quality DCE-MRI examination requires a good understanding of the technical aspects and limitations of image acquisition and postprocessing techniques.

Prostate Magnetic Resonance Imaging and Magnetic Resonance Imaging Targeted Biopsy in Patients with a Prior Negative Biopsy: A Consensus Statement by AUA and SAR

PURPOSE After an initial negative biopsy there is an ongoing need for strategies to improve patient selection for repeat biopsy as well as the diagnostic yield from repeat biopsies. MATERIALS AND METHODS As a collaborative initiative of the AUA (American Urological Association) and SAR (Society of Abdominal Radiology) Prostate Cancer Disease Focused Panel, an expert panel of urologists and radiologists conducted a literature review and formed consensus statements regarding the role of prostate magnetic resonance imaging and magnetic resonance imaging targeted biopsy in patients with a negative biopsy, which are summarized in this review. RESULTS The panel recognizes that many options exist for men with a previously negative biopsy. If a biopsy is recommended, prostate magnetic resonance imaging and subsequent magnetic resonance imaging targeted cores appear to facilitate the detection of clinically significant disease over standardized repeat biopsy. Thus, when high quality prostate magnetic resonance imaging is available, it should be strongly considered for any patient with a prior negative biopsy who has persistent clinical suspicion for prostate cancer and who is under evaluation for a possible repeat biopsy. The decision of whether to perform magnetic resonance imaging in this setting must also take into account the results of any other biomarkers and the cost of the examination, as well as the availability of high quality prostate magnetic resonance imaging interpretation. If magnetic resonance imaging is done, it should be performed, interpreted and reported in accordance with PI-RADS version 2 (v2) guidelines. Experience of the reporting radiologist and biopsy operator are required to achieve optimal results and practices integrating prostate magnetic resonance imaging into patient care are advised to implement quality assurance programs to monitor targeted biopsy results. CONCLUSIONS Patients receiving a PI-RADS assessment category of 3 to 5 warrant repeat biopsy with image guided targeting. While transrectal ultrasound guided magnetic resonance imaging fusion or in-bore magnetic resonance imaging targeting may be valuable for more reliable targeting, especially for lesions that are small or in difficult locations, in the absence of such targeting technologies cognitive (visual) targeting remains a reasonable approach in skilled hands. At least 2 targeted cores should be obtained from each magnetic resonance imaging defined target. Given the number of studies showing a proportion of missed clinically significant cancers by magnetic resonance imaging targeted cores, a case specific decision must be made whether to also perform concurrent systematic sampling. However, performing solely targeted biopsy should only be considered once quality assurance efforts have validated the performance of prostate magnetic resonance imaging interpretations with results consistent with the published literature. In patients with negative or low suspicion magnetic resonance imaging (PI-RADS assessment category of 1 or 2, respectively), other ancillary markers (ie PSA, PSAD, PSAV, PCA3, PHI, 4K) may be of value in identifying patients warranting repeat systematic biopsy, although further data are needed on this topic. If a repeat biopsy is deferred on the basis of magnetic resonance imaging findings, then continued clinical and laboratory followup is advised and consideration should be given to incorporating repeat magnetic resonance imaging in this diagnostic surveillance regimen.

Prostate MRI and 3D MR Spectroscopy: How We Do It

OBJECTIVE This review is a primer on the technical aspects of performing a high-quality MRI and MR spectroscopic imaging examination of the prostate. CONCLUSION MRI and MR spectroscopic imaging are useful tools in the localization, staging, and functional assessment of prostate cancer. Performing a high-quality MR spectroscopic examination requires understanding of the technical aspects and limitations of spectral acquisition, postprocessing techniques, and spectral evaluation.

MR Enterography of Crohn Disease: Part 1, Rationale, Technique, and Pitfalls

OBJECTIVE The purpose of this article is to review the technique of performing MR enterography examinations and to review the imaging findings suggestive of Crohn disease. This article will also allow the reader to self-assess and improve his or her skills in the performance and interpretation of MR enterography examinations. CONCLUSION MRI plays a valuable role in providing accurate information about the severity of and complications related to Crohn disease and can help in guiding surgical or medical treatment.

MR Enterography of Crohn Disease: Part 2, Imaging and Pathologic Findings

OBJECTIVE The purpose of this article is to review MR enterography technique and imaging findings suggestive of Crohn disease on these examinations. This article will also allow the reader to self-assess and improve his or her skills in the performance and interpretation of MR enterography examinations. CONCLUSION This article reviews the technique of performing MR enterography examinations. MRI plays a valuable role in providing accurate information about severity of and complications related to Crohn disease and can help in guiding surgical or medical treatment.

The role of magnetic resonance imaging (MRI) in focal therapy for prostate cancer: recommendations from a consensus panel

To establish a consensus on the utility of multiparametric magnetic resonance imaging (mpMRI) to identify patients for focal therapy.

Urinary bladder cancer: Role of MR imaging

Urinary bladder cancer is a heterogeneous disease with a variety of pathologic features, cytogenetic characteristics, and natural histories. It is the fourth most common cancer in males and the tenth most common cancer in females. Urinary bladder cancer has a high recurrence rate, necessitating long-term surveillance after initial therapy. Early detection is important, since up to 47% of bladder cancer-related deaths may have been avoided. Conventional computed tomography (CT) and magnetic resonance (MR) imaging are only moderately accurate in the diagnosis and local staging of bladder cancer, with cystoscopy and pathologic staging remaining the standards of reference. However, the role of newer MR imaging sequences (eg, diffusion-weighted imaging) in the diagnosis and local staging of bladder cancer is still evolving. Substantial advances in MR imaging technology have made multiparametric MR imaging a feasible and reasonably accurate technique for the local staging of bladder cancer to optimize treatment. In addition, whole-body CT is the primary imaging technique for the detection of metastases in bladder cancer patients, especially those with disease that invades muscle.

A clinically relevant approach to imaging prostate cancer: review.

The zonal anatomy of the prostate is likened to a cone containing a scoop of ice cream [5, 6]. The cone is the peripheral zone and makes up 70% of the prostate gland by volume in young men. The ducts of the peripheral zone glands drain to the distal prostatic urethra. The scoop of ice cream is the central zone and makes up 25% of the prostate gland volume in young men. The ejaculatory ducts traverse the central zone, and the ducts of the central zone drain to the region of the verumontanum clustered around the entry of the ejaculatory ducts. The remaining 5% of the prostate consists of the transition zone, which is composed of two small bulges of tissue that surround the anterior and lateral parts of the proximal urethra in a horseshoelike fashion (Fig. 1). This two-compartment model is deficient anteriorly where the peripheral zone is interrupted by the anterior fibromuscular stroma, a band of smooth muscle mixed with fibrous tissue that forms a thick shield over the anterior aspect of the gland. As a result, the peripheral zone lies predominantly lateral and posterior to the central zone. The prostate zones are defined histologically and therefore many prostatic diseases have a zonal distribution. Seventy percent of adenocarcinomas arise in the peripheral zone and 20% of adenocarcinomas arise in the transition zone, while only 10% of adenocarcinomas arise in the central zone. Prostate adenocarcinomas arise in the glandular components of the prostate [5].