Whole-body MRI (WB-MRI) versus axial skeleton MRI (AS-MRI) to detect and measure bone metastases in prostate cancer (PCa)

Evaluating prostate cancer bone metastasis using accelerated whole-body isotropic 3D T1-weighted Dixon MRI with compressed SENSE: a feasibility study

OBJECTIVES

The study aimed to assess the efficiency of whole-body high-resolution compressed sensing-sensitivity encoding isotropic T1-Weighted Dixon (CSI-T1W-Dixon) scans in evaluating bone metastasis.

METHODS

Forty-five high-risk prostate cancer patients with bone metastases were enrolled prospectively and underwent whole-body MRI sequences, which included the following: pre- and post-contrast CSI-T1W-Dixon and conventional multi-planar T1-Weighted Dixon (CMP-T1W-Dixon) (coronal, sagittal, and axial scans), short tau inversion recovery (STIR), and DWI. Comparison between the CMP-T1W-Dixon and CSI-T1W-Dixon images was done for the subjective image quality, the quantitative contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR). Furthermore, the diagnostic performance based on per-lesion and per-patient basis utilizing non-contrast T1-weighted (T1)/T1+ contrasted T1-weighted (T1C)/T1 + T1C + STIR + DWI sequences was compared between the CSI-T1W-Dixon and CMP-T1W-Dixon methods using reference standards (combining biopsy data and 6-month imaging follow-up).

RESULT

The CSI-T1W-Dixon images produced fewer image artifacts in the axial and coronal planes compared to the CMP-T1W-Dixon images. Also, the CSI-T1W-Dixon images provided better a CNR in fat-only images of all three planes and water-only images of the axial plane (p < 0.05). The CSI-T1W-Dixon showed a higher sensitivity than the CMP-T1W-Dixon techniques in analyzing T1-only images on a per-lesion basis (82.7% vs. 53.8% for sensitivity, p = 0.03). On a per-patient basis, no difference was found in the diagnostic capacity between the CSI-T1W-Dixon and CMP-T1W-Dixon sequences either alone or in combinations (p = 0.57-1).

CONCLUSION

High-resolution CSI-T1W-Dixon with higher image quality and diagnostic capacity can replace the CMP-T1W-Dixon method in evaluating bone metastasis in clinical practice.

KEY POINTS

• Compressed sensing isotropic acquisition for 3D T1-weighted Dixon images can improve the image quality with fewer artifacts compared to the anisotropic multiplanar acquisition. • Compressed sensing isotropic acquisition can save 67% of scanning time compared to anisotropic multiplanar acquisition. • Compressed sensing isotropic 3D T1-weighted Dixon images can offer better diagnostic performance with higher sensitivity compared to anisotropic multiplanar images.

Management of Patients with Advanced Prostate Cancer. Part I: Intermediate-/High-risk and Locally Advanced Disease, Biochemical Relapse, and Side Effects of Hormonal Treatment: Report of the Advanced Prostate Cancer Consensus Conference 2022

BACKGROUND

Innovations in imaging and molecular characterisation and the evolution of new therapies have improved outcomes in advanced prostate cancer. Nonetheless, we continue to lack high-level evidence on a variety of clinical topics that greatly impact daily practice. To supplement evidence-based guidelines, the 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) surveyed experts about key dilemmas in clinical management.

OBJECTIVE

To present consensus voting results for select questions from APCCC 2022.

DESIGN, SETTING, AND PARTICIPANTS

Before the conference, a panel of 117 international prostate cancer experts used a modified Delphi process to develop 198 multiple-choice consensus questions on (1) intermediate- and high-risk and locally advanced prostate cancer, (2) biochemical recurrence after local treatment, (3) side effects from hormonal therapies, (4) metastatic hormone-sensitive prostate cancer, (5) nonmetastatic castration-resistant prostate cancer, (6) metastatic castration-resistant prostate cancer, and (7) oligometastatic and oligoprogressive prostate cancer. Before the conference, these questions were administered via a web-based survey to the 105 physician panel members ("panellists") who directly engage in prostate cancer treatment decision-making. Herein, we present results for the 82 questions on topics 1-3.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Consensus was defined as ≥75% agreement, with strong consensus defined as ≥90% agreement.

RESULTS AND LIMITATIONS

The voting results reveal varying degrees of consensus, as is discussed in this article and shown in the detailed results in the Supplementary material. The findings reflect the opinions of an international panel of experts and did not incorporate a formal literature review and meta-analysis.

CONCLUSIONS

These voting results by a panel of international experts in advanced prostate cancer can help physicians and patients navigate controversial areas of clinical management for which high-level evidence is scant or conflicting. The findings can also help funders and policymakers prioritise areas for future research. Diagnostic and treatment decisions should always be individualised based on patient and cancer characteristics (disease extent and location, treatment history, comorbidities, and patient preferences) and should incorporate current and emerging clinical evidence, therapeutic guidelines, and logistic and economic factors. Enrolment in clinical trials is always strongly encouraged. Importantly, APCCC 2022 once again identified important gaps (areas of nonconsensus) that merit evaluation in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with health care providers and patients worldwide. At each APCCC, a panel of physician experts vote in response to multiple-choice questions about their clinical opinions and approaches to managing advanced prostate cancer. This report presents voting results for the subset of questions pertaining to intermediate- and high-risk and locally advanced prostate cancer, biochemical relapse after definitive treatment, advanced (next-generation) imaging, and management of side effects caused by hormonal therapies. The results provide a practical guide to help clinicians and patients discuss treatment options as part of shared multidisciplinary decision-making. The findings may be especially useful when there is little or no high-level evidence to guide treatment decisions.

Whole-body MRI in oncology: can a single anatomic T2 Dixon sequence replace the combination of T1 and STIR sequences to detect skeletal metastasis and myeloma?

OBJECTIVES

To compare the diagnostic accuracy of a single T2 Dixon sequence to the combination T1+STIR as anatomical sequences used for detecting tumoral bone marrow lesions in whole-body MRI (WB-MRI) examinations.

METHODS

Between January 2019 and January 2020, seventy-two consecutive patients (55 men, 17 women, median age = 66 years) with solid (prostate, breast, neuroendocrine) cancers at high risk of metastasis or proven multiple myeloma (MM) prospectively underwent a WB-MRI examination including coronal T1, STIR, T2 Dixon and axial diffusion-weighted imaging sequences. Two radiologists independently assessed the combination of T1+STIR sequences and the fat+water reconstructions from the T2 Dixon sequence. The reference standard was established by consensus reading of WB-MRI and concurrent imaging available at baseline and at 6 months. Repeatability and reproducibility of MRI scores (presence and semi-quantitative count of lesions), image quality (SNR: signal-to-noise, CNR: contrast-to-noise, CRR: contrast-to-reference ratios), and diagnostic characteristics (Se: sensitivity, Sp: specificity, Acc: accuracy) were assessed per-skeletal region and per-patient.

RESULTS

Repeatability and reproducibility were at least good regardless of the score, region, and protocol (0.67 ≤ AC1 ≤ 0.98). CRR was higher on T2 Dixon fat compared to T1 (p < 0.0001) and on T2 Dixon water compared to STIR (p = 0.0128). In the per-patient analysis, Acc of the T2 Dixon fat+water was higher than that of T1+STIR for the senior reader (Acc = +0.027 [+0.025; +0.029], p < 0.0001) and lower for the junior reader (Acc = -0.029 [-0.031; -0.027], p < 0.0001).

CONCLUSIONS

A single T2 Dixon sequence with fat+water reconstructions offers similar reproducibility and diagnostic accuracy as the recommended combination of T1+STIR sequences and can be used for skeletal screening in oncology, allowing significant time-saving.

KEY POINTS

• Replacement of the standard anatomic T1 + STIR WB-MRI protocol by a single T2 Dixon sequence drastically shortens the examination time without loss of diagnostic accuracy. • A protocol based on fat + water reconstructions from a single T2 Dixon sequence offers similar inter-reader agreement and a higher contrast-to-reference ratio for detecting lesions compared to the standard T1 + STIR protocol. • Differences in the accuracy between the two protocols are marginal (+ 3% in favor of the T2 Dixon with the senior reader; -3% against the T2 Dixon with the junior reader).

Whole-body MRI: detecting bone metastases from prostate cancer

Whole-body magnetic resonance imaging (WB-MRI) is currently used worldwide for detecting bone metastases from prostate cancer. The 5-year survival rate for prostate cancer is > 95%. However, an increase in survival time may increase the incidence of bone metastasis. Therefore, detecting bone metastases is of great clinical interest. Bone metastases are commonly located in the spine, pelvis, shoulder, and distal femur. Bone metastases from prostate cancer are well-known representatives of osteoblastic metastases. However, other types of bone metastases, such as mixed or inter-trabecular type, have also been detected using MRI. MRI does not involve radiation exposure and has good sensitivity and specificity for detecting bone metastases. WB-MRI has undergone gradual developments since the last century, and in 2004, Takahara et al., developed diffusion-weighted Imaging (DWI) with background body signal suppression (DWIBS). Since then, WB-MRI, including DWI, has continued to play an important role in detecting bone metastases and monitoring therapeutic effects. An imaging protocol that allows complete examination within approximately 30 min has been established. This review focuses on WB-MRI standardization and the automatic calculation of tumor total diffusion volume (tDV) and mean apparent diffusion coefficient (ADC) value. In the future, artificial intelligence (AI) will enable shorter imaging times and easier automatic segmentation.

Imaging of treatment response and minimal residual disease in multiple myeloma: state of the art WB-MRI and PET/CT

Bone imaging has been intimately associated with the diagnosis and staging of multiple myeloma (MM) for more than 5 decades, as the presence of bone lesions indicates advanced disease and dictates treatment initiation. The methods used have been evolving, and the historical radiographic skeletal survey has been replaced by whole body CT, whole body MRI (WB-MRI) and [¹⁸F]FDG-PET/CT for the detection of bone marrow lesions and less frequent extramedullary plasmacytomas.Beyond diagnosis, imaging methods are expected to provide the clinician with evaluation of the response to treatment. Imaging techniques are consistently challenged as treatments become more and more efficient, inducing profound response, with more subtle residual disease. WB-MRI and FDG-PET/CT are the methods of choice to address these challenges, being able to assess disease progression or response and to detect "minimal" residual disease, providing key prognostic information and guiding necessary change of treatment.This paper provides an up-to-date overview of the WB-MRI and PET/CT techniques, their observations in responsive and progressive disease and their role and limitations in capturing minimal residual disease. It reviews trials assessing these techniques for response evaluation, points out the limited comparisons between both methods and highlights their complementarity with most recent molecular methods (next-generation flow cytometry, next-generation sequencing) to detect minimal residual disease. It underlines the important role of PET/MRI technology as a research tool to compare the effectiveness and complementarity of both methods to address the key clinical questions.

Bone Metastases Are Measurable: The Role of Whole-Body MRI and Positron Emission Tomography

Metastatic tumor deposits in bone marrow elicit differential bone responses that vary with the type of malignancy. This results in either sclerotic, lytic, or mixed bone lesions, which can change in morphology due to treatment effects and/or secondary bone remodeling. Hence, morphological imaging is regarded unsuitable for response assessment of bone metastases and in the current Response Evaluation Criteria In Solid Tumors 1.1 (RECIST1.1) guideline bone metastases are deemed unmeasurable. Nevertheless, the advent of functional and molecular imaging modalities such as whole-body magnetic resonance imaging (WB-MRI) and positron emission tomography (PET) has improved the ability for follow-up of bone metastases, regardless of their morphology. Both these modalities not only have improved sensitivity for visual detection of bone lesions, but also allow for objective measurements of bone lesion characteristics. WB-MRI provides a global assessment of skeletal metastases and for a one-step "all-organ" approach of metastatic disease. Novel MRI techniques include diffusion-weighted imaging (DWI) targeting highly cellular lesions, dynamic contrast-enhanced MRI (DCE-MRI) for quantitative assessment of bone lesion vascularization, and multiparametric MRI (mpMRI) combining anatomical and functional sequences. Recommendations for a homogenization of MRI image acquisitions and generalizable response criteria have been developed. For PET, many metabolic and molecular radiotracers are available, some targeting tumor characteristics not confined to cancer type (e.g. 18F-FDG) while other targeted radiotracers target specific molecular characteristics, such as prostate specific membrane antigen (PSMA) ligands for prostate cancer. Supporting data on quantitative PET analysis regarding repeatability, reproducibility, and harmonization of PET/CT system performance is available. Bone metastases detected on PET and MRI can be quantitatively assessed using validated methodologies, both on a whole-body and individual lesion basis. Both have the advantage of covering not only bone lesions but visceral and nodal lesions as well. Hybrid imaging, combining PET with MRI, may provide complementary parameters on the morphologic, functional, metabolic and molecular level of bone metastases in one examination. For clinical implementation of measuring bone metastases in response assessment using WB-MRI and PET, current RECIST1.1 guidelines need to be adapted. This review summarizes available data and insights into imaging of bone metastases using MRI and PET.

Whole-Body MRI in Rheumatology: Major Advances and Future Perspectives

Whole-body magnetic resonance imaging is constantly gaining more importance in rheumatology, particularly for what concerns the diagnosis, follow-up, and treatment response evaluation. Initially applied principally for the study of ankylosing spondylitis, in the last years, its use has been extended to several other rheumatic diseases. Particularly in the pediatric population, WB-MRI is rapidly becoming the gold-standard technique for the diagnosis and follow-up of both chronic recurrent multifocal osteomyelitis and juvenile spondyloarthritis. In this review, we analyze the benefits and limits of this technique as well as possible future applications.

[MRI of the axial skeleton for evaluation of prostate cancer extent in french Guyana]

INTRODUCTION

Spread evaluation of Prostate Cancer (PC) in French Guyana is bothered by the lack of bone scintigraphy. The availability of 4 MRI allows to develop alternatives using Axial Skeleton MRI (AS MRI). We report the related results.

MATERIAL

AS MRI was done in patients with diagnosis of high risk PC: PSA>=10ng/ml and/or Gleason Score>=7 (predominant Gleason grade 4) and/or clinical T2b and/or T2b/T3 MRI and/or >50% positive biopsies. AS MRI was including spine, pelvis and skull assessement.The results were systematically compared to the clinical, biological and biopsy features.

RESULTS

Amongst 163 AS MRI performed, 30 were positive and 133 negative. Of these 133 patients, 60 were submited to radical prostatectomy with or without lymphadenectomy. In these 133 patients with negative AS MRI, median PSA was 11ng/ml (1-51) and 27 (20,3%) had PSA>20ng/ml. In patients with positive AS MRI, only 1 had PSA<20ng/ml and predominant Gleason grade 3.

CONCLUSION

Our study shows that AS MRI assessement is especially usefull in patients who are most likely to have bone metastasis that is to say those with PSA>20ng/ml and/or predominant Gleason grade 4.

LEVEL OF EVIDENCE

3.

Whole-body MRI-based multivariate prediction model in the assessment of bone metastasis in prostate cancer

PURPOSE

A whole-body MRI (WB-MRI) including T1, short time inversion recovery (STIR), diffusion-weighted imaging (high b value) was applied in our center for the detection of bone metastasis in prostate cancer (PCa) patients. We intended to assess the diagnostic performance of this examination.

METHODS

547 cases of PCa patients with higher risk of metastasis were referred to bone scintigraphy with SPECT/CT (BS + SPECT/CT) and whole-body MRI in Shanghai Changhai Hospital. Best valuable comparator (BVC) was applied for the final diagnosis of metastasis. A panel of radiologists interpreted the results. Decision curve analysis (DCA) and receiver operating characteristic curve (ROC) analysis were applied.

RESULTS

Bone metastasis was diagnosed in 110 cases, and others were non-metastatic by BVC. The area under the receiver operating characteristic curve (AUC) was higher in WB-MRI (0.778) than BS + SPECT/CT (0.634, p < 0.001). A WB-MRI-based prediction model was established with AUC of 0.877. Internal validation showed that the predictive model was well-calibrated. The DCA demonstrated that the model had higher net benefit than the BS + SPECT/CT-based model.

CONCLUSION

WB-MRI is more effective in identifying metastasis in PCa patients than BS + SPECT/CT. The prediction model combined WB-MRI with clinical parameters may be a promising approach to the assessment of metastasis.

Comparison of PET/CT and MRI in the Diagnosis of Bone Metastasis in Prostate Cancer Patients: A Network Analysis of Diagnostic Studies

BACKGROUND

Accurate diagnosis of bone metastasis status of prostate cancer (PCa) is becoming increasingly more important in guiding local and systemic treatment. Positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (MRI) have increasingly been utilized globally to assess the bone metastases in PCa. Our meta-analysis was a high-volume series in which the utility of PET/CT with different radioligands was compared to MRI with different parameters in this setting.

MATERIALS AND METHODS

Three databases, including Medline, Embase, and Cochrane Library, were searched to retrieve original trials from their inception to August 31, 2019 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. The methodological quality of the included studies was assessed by two independent investigators utilizing Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). A Bayesian network meta-analysis was performed using an arm-based model. Absolute sensitivity and specificity, relative sensitivity and specificity, diagnostic odds ratio (DOR), and superiority index, and their associated 95% confidence intervals (CI) were used to assess the diagnostic value.

RESULTS

Forty-five studies with 2,843 patients and 4,263 lesions were identified. Network meta-analysis reveals that 68Ga-labeled prostate membrane antigen (68Ga-PSMA) PET/CT has the highest superiority index (7.30) with the sensitivity of 0.91 and specificity of 0.99, followed by 18F-NaF, 11C-choline, 18F-choline, 18F-fludeoxyglucose (FDG), and 18F-fluciclovine PET/CT. The use of high magnetic field strength, multisequence, diffusion-weighted imaging (DWI), and more imaging planes will increase the diagnostic value of MRI for the detection of bone metastasis in prostate cancer patients. Where available, 3.0-T high-quality MRI approaches 68Ga-PSMA PET/CT was performed in the detection of bone metastasis on patient-based level (sensitivity, 0.94 vs. 0.91; specificity, 0.94 vs. 0.96; superiority index, 4.43 vs. 4.56).

CONCLUSIONS

68Ga-PSMA PET/CT is recommended for the diagnosis of bone metastasis in prostate cancer patients. Where available, 3.0-T high-quality MRI approaches 68Ga-PSMA PET/CT should be performed in the detection of bone metastasis.

Whole-body magnetic resonance imaging for prostate cancer assessment: Current status and future directions

Over the past decade, updated definitions for the different stages of prostate cancer and risk for distant disease, along with the advent of new therapies, have remarkably changed the management of patients. The two expectations from imaging are accurate staging and appropriate assessment of disease response to therapies. Modern, next-generation imaging (NGI) modalities, including whole-body magnetic resonance imaging (WB-MRI) and nuclear medicine (most often prostate-specific membrane antigen [PSMA] positron emission tomography [PET]/computed tomography [CT]) bring added value to these imaging tasks. WB-MRI has proven its superiority over bone scintigraphy (BS) and CT for the detection of distant metastasis, also providing reliable evaluations of disease response to treatment. Comparison of the effectiveness of WB-MRI and molecular nuclear imaging techniques with regard to indications and the definition of their respective/complementary roles in clinical practice is ongoing. This paper illustrates the evolution of WB-MRI imaging protocols, defines the current state-of-the art, and highlights the latest developments and future challenges. The paper presents and discusses WB-MRI indications in the care pathway of men with prostate cancer in specific key situations: response assessment of metastatic disease, "all in one" cancer staging, and oligometastatic disease.

The prevalence and locations of bone metastases using whole-body MRI in treatment-naïve intermediate- and high-risk prostate cancer

Objective

The aim of this study was to assess the prevalence and distribution of bone metastases in treatment-naïve prostate cancer patients eligible for a metastatic workup using whole-body MRI, and to evaluate the results in light of current guidelines.

Methods

This single-institution, retrospective study included all patients with treatment-naïve prostate cancer referred to whole-body MRI during 2016 and 2017. All were eligible for a metastatic workup according to the guidelines: PSA > 20 ng/ml and/or Gleason grade group ≥ 3 and/or cT ≥ 2c and/or bone symptoms. The definition of a metastasis was descriptive and based on the original MRI reports. The anatomical location of metastases was registered.

Results

We included 161 patients with newly diagnosed prostate cancer of which 36 (22%) were intermediate-risk and 125 (78%) were high-risk. The median age and PSA were 71 years (IQR 64–76) and 13 ng/ml (IQR 8–28), respectively. Bone metastases were found in 12 patients (7%, 95% CI: 4–13), and all were high-risk with Gleason grade group ≥ 4. The pelvis was affected in 4 patients, and the spine + pelvis in the remaining 8. No patients demonstrated metastases to the spine without concomitant metastases in the pelvis. Limitations are the small number of metastases and retrospective design.

Conclusion

This study suggests that the overall prevalence of bone metastases using the current guidelines for screening is quite low. No metastases were seen in the case of Gleason grade group ≤ 3, and further studies should investigate if it necessary to screen non-high-risk patients.

Key Points

• The overall prevalence of bone metastases was 7% in the case of newly diagnosed intermediate- and high-risk prostate cancer.

• The prevalence in high-risk patients was 10%, and no metastases were seen in patients with Gleason grade group ≤ 3.

• The pelvic skeleton is the main site, and no metastases occurred in the spine without concomitant pelvic metastases.

Comparison of PSMA-PET/CT, choline-PET/CT, NaF-PET/CT, MRI, and bone scintigraphy in the diagnosis of bone metastases in patients with prostate cancer: a systematic review and meta-analysis

OBJECTIVE

A systematic review and meta-analysis to compare the diagnostic performance of prostate-specific membrane antigen (PSMA)-PET/CT, choline-PET/CT, Sodium Fluoride (NaF) PET/CT, MRI, and bone scintigraphy (BS) in detecting bone metastases in patients with prostate cancer.

METHODS

We searched PubMed and Embase for articles published between January 1990 and September 2018. Two evaluators independently extracted the sensitivity, specificity, the numbers of true and false positives, and true and false negatives. We calculated the pooled sensitivity, specificity, and 95% confidence intervals (CI) for each method. We calculated the tests' diagnostic odds ratios (DOR); drew the summary receiver operating characteristic (SROC) curves; and obtained the areas under the curves (AUC), Q* values, and 95% CIs.

RESULTS

The per-patient pooled sensitivities of PSMA-PET/CT, choline-PET/CT, NaF-PET/CT, MRI, and BS were 0.97, 0.87, 0.96, 0.91, and 0.86, respectively. The pooled specificities were 1.00, 0.99, 0.97, 0.96, and 0.95, respectively. The pooled DOR values were 504.16, 673.67, 242.63, and 114.44, respectively. The AUC were 1.00, 0.99, 0.99, 0.98, and 0.95, respectively. The per-lesion pooled sensitivities of PSMA-PET/CT, choline-PET/CT, NaF-PET/CT, MRI, and bone imaging were 0.88, 0.80, 0.97, 0.81 and 0.68, respectively.

CONCLUSIONS

According to the meta-analysis, PSMA-PET/CT had the highest per-patient sensitivity and specificity in detecting bone metastases with prostate cancer. The sensitivities of NaF-PET/CT and MRI were better than those for choline-PET/CT and BS. The specificity of PSMA-PET/CT was significantly better than BS. Others were similar. For per-lesion, NaF-PET/CT had the highest sensitivity, PSMA-PET/CT had higher sensitivity than choline-PET/CT and MRI, and BS had the lowest sensitivity.

Integrating Bipartite Network Projection and KATZ Measure to Identify Novel CircRNA-Disease Associations

Accumulating biological experiments have shown that circRNAs are closely related to the occurrence and development of many complex human diseases. During recent years, the associations of circRNA with disease have caused more and more researchers to pay attention and to analyze their correlation mechanisms. However, experimental methods for determining the associations of circRNA with a particular disease are still expensive, difficult, and time consuming. Moreover, the available databases related to circRNA-disease correlations have only recently been updated, and only a few computational methods are constructed to predict potential circRNA-disease correlations. Taking into account the limitations of experimental studies, we develop a novel computational method, named IBNPKATZ, for predicting potential circRNA-disease associations, which integrates the bipartite network projection algorithm and KATZ measure. This model is based on the known circRNA-disease associations, combining circRNA similarity and disease similarity. Specifically, the circRNA similarity is derived from the average of the semantic similarity and the Gaussian interaction profile (GIP) kernel similarity of circRNA. Similarly, disease similarity is the mean of the semantic similarity and the GIP kernel similarity of disease. Furthermore, it is semi-supervised and does not require negative samples. Finally, IBNPKATZ achieves reliable AUC of 0.9352 in the leave-one-out cross validation, and case studies show that the circRNA-disease correlations predicted by our method can be successfully demonstrated by relevant experiments. The IBNPKATZ is expected to be a useful biomedical research tool for predicting potential circRNA-disease associations.

Multiparametric whole-body 3.0-T MRI in newly diagnosed intermediate- and high-risk prostate cancer: diagnostic accuracy and interobserver agreement for nodal and metastatic staging

OBJECTIVES

To determine the diagnostic accuracy and interobserver concordance of whole-body (WB)-MRI, vs. 99mTc bone scintigraphy (BS) and 18fluoro-ethyl-choline (18F-choline) PET/CT for the primary staging of intermediate/high-risk prostate cancer.

METHODS

An institutional review board approved prospective cohort study carried out between July 2012 and November 2015, whereby 56 men prospectively underwent 3.0-T multiparametric (mp)-WB-MRI in addition to BS (all patients) ± 18F-choline PET/CT (33 patients). MRI comprised pre- and post-contrast modified Dixon (mDixon), T2-weighted (T2W) imaging, and diffusion-weighted imaging (DWI). Patients underwent follow-up mp-WB-MRI at 1 year to derive the reference standard. WB-MRIs were reviewed by two radiologists applying a 6-point scale and a locked sequential read (LSR) paradigm for the suspicion of nodal (N) and metastatic disease (M1a and M1b).

RESULTS

The mean sensitivity/specificity of WB-MRI for N1 disease was 1.00/0.96 respectively, compared with 1.00/0.82 for 18F-choline PET/CT. The mean sensitivity and specificity of WB-MRI, 18F-choline PET/CT, and BS were 0.90/0.88, 0.80/0.92, and 0.60/1.00 for M1b disease. ROC-AUC did not show statistically significant improvement for each component of the LSR; mean ROC-AUC 0.92, 0.94, and 0.93 (p < 0.05) for mDixon + DWI, + T2WI, and + contrast respectively. WB-MRI had an interobserver concordance (κ) of 0.79, 0.68, and 0.58 for N1, M1a, and M1b diseases respectively.

CONCLUSIONS

WB-MRI provides high levels of diagnostic accuracy for both nodal and metastatic bone disease, with higher levels of sensitivity than BS for metastatic disease, and similar performance to 18F-choline PET/CT. T2 and post-contrast mDixon had no significant additive value above a protocol comprising mDixon and DWI alone.

KEY POINTS

• A whole-body MRI protocol comprising unenhanced mDixon and diffusion-weighted imaging provides high levels of diagnostic accuracy for the primary staging of intermediate- and high-risk prostate cancer. • The diagnostic accuracy of whole-body MRI is much higher than that of bone scintigraphy, as currently recommended for clinical use. • Staging using WB-MRI, rather than bone scintigraphy, could result in better patient stratification and treatment delivery than is currently provided to patients worldwide.

Diagnosis of metastasis in castration-resistant prostate cancer patients: decision algorithm in imaging tests

INTRODUCTION

In castration-resistant prostate cancer (CRPC), early detection of metastases is essential for the selection of treatment, and prevention of bone complications. However detecting incipient metastases remains a challenge as the conventional radiological tests (bone scintigraphy or computerised tomography) lack sufficient sensitivity. Diagnostic imaging techniques are currently available that have greater sensitivity and specificity, but are little used due to shortfalls in the recommendations.

OBJECTIVE

To create an algorithm that indicates the most suitable diagnostic imaging techniques for the different M0 CRPC patient profiles based on the scientific evidence.

EVIDENCE ACQUISITION

Meetings were held with eight experts in Urology, Pathological Anatomy, Radiodiagnostics and Nuclear Medicine organised by the Andalusian Association of Urology, in which the recommendations and scientific evidence on each of the diagnostic imaging techniques were reviewed.

SUMMARY OF THE EVIDENCE

We present the current recommendations for the detection of metastasis in M0 CRPC patients, the patients that would benefit from early detection, and summarise the evidence to support the use of each of the new techniques.

CONCLUSIONS

Techniques such as ¹⁸F-Choline PET/CT or DWWB MRI and probably open MRI have been demonstrated to have good sensitivity and specificity for patients with low PSA (<10ng/ml). Their inclusion in routine clinical practice will help improve the early detection of metastasis in CRPC patients.

Comparison of bone lesion distribution between prostate cancer and multiple myeloma with whole-body MRI

PURPOSE

To assess the distribution of bone lesions in patients with prostate cancer (PCa) and those with multiple myeloma (MM) using whole-body magnetic resonance imaging (MRI); and to assess the added value of four anatomical regions located outside the thoraco-lumbo-pelvic area to detect the presence of bone lesions in a patient-based perspective.

MATERIALS AND METHODS

Fifty patients (50 men; mean age, 67±10 [SD] years; range, 59-87 years) with PCa and forty-seven patients (27 women, 20 men; mean age, 62.5±9 [SD] years; range, 47-90 years) with MM were included. Three radiologists assessed bone involvement in seven anatomical areas reading all MRI sequences.

RESULTS

In patients with PCa, there was a cranio-caudal increasing prevalence of metastases (22% [11/50] in the humeri and cervical spine to 60% [30/50] in the pelvis). When the thoraco-lumbo-pelvic region was not involved, the prevalence of involvement of the cervical spine, proximal humeri, ribs, or proximal femurs was 0% in patients with PCa and≥4% (except for the cervical spine, 0%) in those with MM.

CONCLUSION

In patients with PCa, there is a cranio-caudal positive increment in the prevalences of metastases and covering the thoraco-lumbo-pelvic area is sufficient to determine the metastatic status of a patient with PCa. In patients with MM, there is added value of screening all regions, except the cervical spine, to detect additional lesions.

Whole-body MRI to assess bone involvement in prostate cancer and multiple myeloma: comparison of the diagnostic accuracies of the T1, short tau inversion recovery (STIR), and high b-values diffusion-weighted imaging (DWI) sequences

PURPOSE

To compare the diagnostic accuracy of whole-body T1, short tau inversion recovery (STIR), high b-value diffusion-weighted imaging (DWI), and sequence combinations to detect bone involvement in prostate cancer (PCa) and multiple myeloma (MM) patients.

MATERIALS AND METHODS

We included 50 consecutive patients with PCa at high risk for metastasis and 47 consecutive patients with a histologically confirmed diagnosis of MM who received whole-body MRI at two institutions from January to December 2015. Coronal T1, STIR, and reconstructed coronal high b-values DWI were obtained for all patients. Two musculoskeletal radiologists read individual sequences, pairs of sequences (T1-DWI, T1-STIR, and STIR-DWI), and all combined (T1-STIR-DWI) to detect bone involvement. Receiver operating characteristic curve analysis was used to assess diagnostic performance according to a "best valuable comparator" combining baseline and 6-month imaging and clinical and biological data. Interobserver agreement was calculated.

RESULTS

Interobserver agreement for individual and combined MRI sequences was very good in the PCa group and ranged from good to very good in the MM group (0.76-1.00). In PCa patients, T1-DWI, T1-STIR, and T1-STIR-DWI showed the highest performance (sensitivity = 100% [95% CI = 90.5-100%], specificity = 100% [75.3-100%]). In MM patients, the highest performance was achieved by T1-STIR-DWI (sensitivity = 100% [88.4-100%], specificity = 94.1% [71.3-100%]). T1-STIR-DWI significantly outperformed all sequences (p < 0.05) except T1-DWI (p = 0.49).

CONCLUSION

In PCa patients, a combination of either T1-DWI or T1-STIR sequences is not inferior to a combination of three sequences to detect bone metastases. In MM, T1-STIR-DWI and T1-DWI had the highest diagnostic performance for detecting bone involvement.

KEY POINTS

• The sequences used in Whole Body MRI studies to detect bone involvement in prostate cancer and myeloma were evaluated. • In prostate cancer, any pairwise combinations of T1, STIR, and DWI have high diagnostic value. • In myeloma, the combinations T1-STIR-DWI or T1-DWI sequences should be used.

RETRACTED: Recommandations françaises du Comité de Cancérologie de l’AFU – Actualisation 2018–2020 : cancer de la prostate French ccAFU guidelines – Update 2018–2020: Prostate cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Cet article est retiré de la publication à la demande des auteurs car ils ont apporté des modifications significatives sur des points scientifiques après la publication de la première version des recommandations. Le nouvel article est disponible à cette adresse: DOI:10.1016/j.purol.2019.01.007. C’est cette nouvelle version qui doit être utilisée pour citer l’article. This article has been retracted at the request of the authors, as it is not based on the definitive version of the text because some scientific data has been corrected since the first issue was published. The replacement has been published at the DOI:10.1016/j.purol.2019.01.007. That newer version of the text should be used when citing the article.

Quantitative Whole-Body Diffusion-Weighted MR Imaging

Whole-body diffusion-weighted MRI has emerged as a powerful diagnostic tool for disease detection and staging mainly used in systemic bone disease. The large field-of-view functional imaging technique highlights cellular tumor and suppresses normal tissue signal, allowing quantification of an estimate of total disease burden, summarized as the total diffusion volume (tDV), as well as global apparent diffusion coefficient (gADC) measurements. Both tDV and gADC have been shown to be repeatable quantitative parameters that indicate tumor heterogeneity and treatment effects, thus potential, noninvasive, imaging biomarkers informing on disease prognosis and therapy response.

Impact of sodium 18F-fluoride PET/CT, 18F-fluorocholine PET/CT and whole-body diffusion-weighted MRI on the management of patients with prostate cancer suspicious for metastasis: a prospective multicentre study

PURPOSE

To compare the impact of 18F-sodium-fluoride (NaF) PET/CT, 18F-fluorocholine (FCH) PET/CT and diffusion-weighted whole-body MRI (DW-MRI) on the management of patients with prostate cancer (PCa) suspicious for distant metastasis.

METHODS

Prostate cancer patients were prospectively included between December 2011 and August 2014 and benefited from these three whole-body imaging (WBI) modalities within 1 month in addition to the standard PCa workup. Management was prospectively decided by clinicians during two multidisciplinary meetings, before and after the whole-body imaging workup. Rates of induced changes of whole-body imaging modalities were compared by Cochran's Q test.

RESULTS

One-hundred-one patients (27 at staging, 59 at first biochemical recurrence (BCR) and 15 at first episode of rising serum level of prostate-specific antigen during androgen-deprivation therapy) were included. The overall rate of management changes was 52%: 29% as a consequence of WBI, higher for FCH-PET/CT than for NaF-PET/CT or DW-MRI (p < 0.0001) and highest (41%) for FCH-PET/CT at BCR. Actual management was adequate in all patients but two.

CONCLUSIONS

Whole-body imaging induced a change in management in approximately a third of PCa patients suspicious for metastasis. The impact rate was determined to be greatest at first BCR using FCH-PET/CT. NaF-PET/CT and DW-MRI seemed less useful in this context.

Comparison of MRI Sequences in Whole-Body PET/MRI for Staging of Patients With High-Risk Prostate Cancer

OBJECTIVE

The purpose of this study is to investigate the diagnostic value of various MRI sequences used for whole-body (WB) ¹⁸F-fluorocholine (FCH) PET/MRI staging of patients with high-risk prostate cancer (PCa).

SUBJECTS AND METHODS

This analysis is based on data from a prospective study that included 58 patients with untreated high-risk PCa who underwent integrated WB FCH PET/MRI (n = 10) or FCH PET/CT and WB MRI (n = 48). Metastatic sites were recorded. The standard of reference was histopathologic findings or clinical and imaging follow-up, or both. For each MRI sequence (Dixon T1-weighted, turbo inversion recovery magnitude, WB DWI, and gadolinium-enhanced T1-weighted volumetric interpolated breath-hold examination [VIBE]), acquisition time was recorded, and conspicuity of metastatic lesions was qualitatively assessed by two radiologists using a 4-point ordinal scale (0-3).

RESULTS

Total WB acquisition times were 1 minute 25 seconds for Dixon T1-weighted, 15 minutes 7 seconds for turbo inversion recovery magnitude, 16 minutes 33 seconds for WB DWI, and 1 minute 28 seconds for gadolinium-enhanced T1-weighted VIBE. The lesion detection rates were 88.3% (68/77) for Dixon T1-weighted, 94.8% (73/77) for turbo inversion recovery magnitude, 95.2% (40/42) for WB DWI, and 97.4% (75/77) for gadolinium-enhanced T1-weighted VIBE sequences. Moderate or high conspicuity scores were assigned to 62.3% (48/77) of lesions for Dixon T1-weighted, 88.3% (68/77) of lesions for turbo inversion recovery magnitude, 90.5% (38/42) of lesions for WB DWI, and 92.2% (71/77) of lesions for gadolinium-enhanced T1-weighted VIBE sequences. Conspicuity of metastases on gadolinium-enhanced T1-weighted VIBE and WB DWI sequences was higher than that on Dixon T1-weighted sequences (p < 0.0001 and p = 0.0011, respectively).

CONCLUSION

Metastases from prostate cancer are best detected at DWI or gadolinium-enhanced T1-weighted VIBE sequences. The most time-efficient sequence with the highest lesion detection rate and conspicuity is gadolinium-enhanced T1-weighted VIBE.

Whole-Body MR Imaging: The Novel, "Intrinsically Hybrid," Approach to Metastases, Myeloma, Lymphoma, in Bones and Beyond

Whole-body MR imaging (WB-MR imaging) has become a modality of choice for detecting bone metastases in multiple cancers, and bone marrow involvement by multiple myeloma or lymphoma. Combination of anatomic and functional sequences imparts an inherently hybrid dimension to this nonirradiating tool and extends the screening of malignancies outside the skeleton. WB-MR imaging outperforms bone scintigraphy and CT and offers an alternative to PET in many tumors by time of lesion detection and assessment of treatment response. Much work has been done to standardize procedures, optimize sequences, validate indications, confirm preliminary research into new applications, rendering clinical application more user-friendly.

Bone Marrow Metastases: T2-weighted Dixon Spin-Echo Fat Images Can Replace T1-weighted Spin-Echo Images

Purpose To test the potential of Dixon T2-weighted fat-only sequences to replace T1-weighted sequences for the detection of bone metastases, with the hypothesis that diagnostic performance with an alternative magnetic resonance (MR) imaging protocol (sagittal spin-echo Dixon T2-weighted fat-only and water-only imaging) would not be inferior to that with the standard protocol (sagittal spin-echo T1-weighted and spin-echo Dixon T2-weighted water-only imaging). Materials and Methods A total of 121 consecutive whole-spine MR imaging examinations (63 men; mean age ± standard deviation, 61.4 years ± 11.8) performed for suspected vertebral bone metastases were included in this retrospective, institutional review board-approved study. Quantitative image analysis was performed for 30 randomly selected spine levels. Qualitative analysis was performed separately by two musculoskeletal radiologists, who registered the number of metastases for each spine level. Areas under the curve with the protocols were compared on the basis of nonparametric receiver operating characteristic curve estimations by using a noninferiority test on paired data, with a best valuable comparator as a reference. Interobserver and interprotocol agreement was assessed by using κ statistics. Results Contrast-to-noise ratio was significantly higher on the alternative protocol images than on the standard protocol images (181.1 [95% confidence interval: 140.4, 221.7] vs 84.7 [95% confidence interval: 66.3, 103.1] respectively; P < .001). Diagnostic performance was not significantly inferior with the alternative protocol than with the standard protocol for both readers in a per-patient analysis (sensitivity, 97.9%-98.9% vs 93.6%-97.9%; specificity, 85.2%-92.6% vs 92.6%-96.3%; area under the curve, 0.92-0.96 vs 0.95, respectively; all P ≤ .02) and a per-spine level analysis (all P < .01). Interobserver and interprotocol agreement was good to very good (κ = 0.70-0.81). Conclusion Dixon T2-weighted fat-only and water-only imaging provide, in one sequence, diagnostic performance similar to that of the standard combination of morphologic sequences for the detection of probable spinal bone metastases, thereby providing an opportunity to reduce imaging time by eliminating the need to perform T1 sequences. ^© RSNA, 2017 An earlier incorrect version of this article appeared online. This article was corrected on November 6, 2017.

Does T1- and diffusion-weighted magnetic resonance imaging give value-added than bone scintigraphy in the follow-up of vertebral metastasis of prostate cancer?

PURPOSE

To evaluate the effectiveness of limited Magnetic Resonance (MR) images including T1- and diffusion-weighted image (DWI) for monitoring vertebral metastasis in patients with prostate cancer.

MATERIALS AND METHODS

From July 2014 to November 2016, patients diagnosed with spinal metastasis from prostate cancer using 99mTc bone scintigraphy were enrolled. Regardless of the primary local therapy, the changes in spinal metastasis were followed up using bone scan and biparametric MR (T1+DWI). All tests were followed up for more than 3 months.

RESULTS

Among the 14 follow-ups of 10 patients, 6 and 10 (including all progressed cases on bone scan) follow-ups were determined to show progressive disease using bone scan and biparametric MR, respectively. Otherwise, we could have predicted neurologic sequela earlier using biparametric MR. Examination time for biparametric MR was 15 minutes, and it was 4 hours for bone scan, respectively.

CONCLUSIONS

Although bone scan has been considered the standard test for bony metastasis in men with prostate cancer, limited MR including T1 and DWI has an additional benefit in monitoring spinal metastasis in patients who are already diagnosed as having spinal metastasis. The limited MR is more sensitive in detecting progressive disease. In addition, it can reduce neurologic complications caused by spinal metastasis.

[CCAFU french national guidelines 2016-2018 on prostate cancer]

OBJECTIVES

The purpose of the guidelines national committee CCAFU was to propose updated french guidelines for localized and metastatic prostate cancer (PCa).

METHODS

A Medline search was achieved between 2013 and 2016, as regards diagnosis, options of treatment and follow-up of PCa, to evaluate different references with levels of evidence.

RESULTS

Epidemiology, classification, staging systems, diagnostic evaluation are reported. Disease management options are detailed. Recommandations are reported according to the different clinical situations. Active surveillance is a major option in low risk PCa. Radical prostatectomy remains a standard of care of localized PCa. The three-dimensional conformal radiotherapy is the technical standard. A dose of > 74Gy is recommended. Moderate hypofractionation provides short-term biochemical control comparable to conventional fractionation. In case of intermediate risk PCa, radiotherapy can be combined with short-term androgen deprivation therapy (ADT). In case of high risk disease, long-term ADT remains the standard of care. ADT is the backbone therapy of metastatic disease. In men with metastases at first presentation, upfront chemotherapy combined with ADT should be considered as a new standard. In case of metastatic castration-resistant PCa (mCRPC), new hormonal treatments and chemotherapy provide a better control of tumor progression and increase survival.

CONCLUSIONS

These updated french guidelines will contribute to increase the level of urological care for the diagnosis and treatment for prostate cancer. © 2016 Elsevier Masson SAS. All rights reserved.

Optimising TNM Staging of Patients with Prostate Cancer Using WB-MRI

Multiparametric Magnetic Resonance Imaging (mp-MRI) is the current standard of reference for the local staging of prostate cancer (PCa). On the other hand, despite the low sensitivity and specificity of Technetium Bone Scanning (BS) for the detection of bone metastases (BM) and of Body Computed Tomography CT for the detection of lymph node metastases (LNM), these techniques are routinely used, in the current clinical practice. Nevertheless, whole Body MRI (WB-MRI) and Positron Emission Tomography Computed Tomography (PET-CT) are emerging as robust tools for the staging of oncologic patients, including those with (PCa).

The available techniques (BS, WB-MRI, PET, CT) for the detection of BM in oncologic patients were compared and showed striking center differences in terms of anatomic sequences and planes used. This heterogeneity and the long acquisition time of WB-MRI protocols – due to the addition of multiple anatomic sequences in different planes – questioned whether a single three dimensional (3D) sequence could replace the multiple anatomic sequences used for node and bone staging of PCa. We demonstrated that WB-MRI is a credible tool for the detection of bone and node metastasis.

The second question addressed the possibility to obtain a complete TNM staging of PCa in a single MRI session. A WB-MRI protocol was developed to enable complete, T (local), N (regional) and M (distant) staging of PCa in a single session, in less than an hour. This ‘all-in-one’ protocol proved to be as efficient as the sum of exams currently in use for the staging of PCa (ie: mp-MRI of the prostate for ‘T’ staging, Thoraco-abdominal CT for ‘N’ staging and bone scintigraphy for ‘M’ staging).

Detecting Tumor Metastases: The Road to Therapy Starts Here

Metastasis is the complex process by which primary tumor cells migrate and establish secondary tumors in an adjacent or distant location in the body. Early detection of metastatic disease and effective therapeutic options for targeting these detected metastases remain impediments to effectively treating patients with advanced cancers. If metastatic lesions are identified early, patients might maximally benefit from effective early therapeutic interventions. Further, monitoring patients whose primary tumors are effectively treated for potential metastatic disease onset is also highly valuable. Finally, patients with metastatic disease can be monitored for efficacy of specific therapeutic interventions through effective metastatic detection techniques. Thus, being able to detect and visualize metastatic lesions is key and provides potential to greatly improve overall patient outcomes. In order to achieve these objectives, researchers have endeavored to mechanistically define the steps involved in the metastatic process as well as ways to effectively detect metastatic progression. We presently overview various preclinical and clinical in vitro and in vivo assays developed to more efficiently detect tumor metastases, which provides the foundation for developing more effective therapies for this invariably fatal component of the cancerous process.

Whole body MRI (WB-MRI) assessment of metastatic spread in prostate cancer: Therapeutic perspectives on targeted management of oligometastatic disease

OBJECTIVES

To determine the proportion of prostate cancer (PCa) patients with oligometastatic disease (≤3 synchronous lesions) using whole body magnetic resonance imaging with diffusion-weighted imaging (WB-MRI/DWI). To determine the proportion of patients with nodal disease confined within currently accepted target areas for extended lymph node dissection (eLND) and pelvic external beam radiation therapy (EBRT).

SUBJECTS AND METHODS

Two radiologists reviewed WB-MRI/DWI studies in 96 consecutive newly diagnosed metastatic PCa patients; 46 patients with newly diagnosed castration naive PCa (mHNPC) and 50 patients with first appearance of metastasis during monitoring for non-metastatic castration resistant PCa (M0 to mCRPC). The distribution of metastatic deposits was assessed and the proportions of patients with oligometastatic disease and with LN metastases located within eLND and EBRT targets were determined.

RESULTS

Twenty-eight percent of mHNPC and 50% of mCPRC entered the metastatic disease with ≤3 sites. Bone metastases (BM) were identified in 68.8% patients; 71.7% of mHNPC and 66% mCRPC patients. Most commonly involved areas were iliac bones and lumbar spine. Enlarged lymph nodes (LN) were detected in 68.7% of patients; 69.6% of mHNPC and 68.0% of mCRPC. Most commonly involved areas were para-aortic, inter-aortico-cava, and external iliac areas. BM and LN were detected concomitantly in 41% of mHNPC and 34% of mCRPC. Visceral metastases were detected in 6.7%. Metastatic disease was confined to LN located within the accepted boundaries of eLND or pelvic EBRT target areas in only ≤25% and ≤30% of patients, respectively.

CONCLUSIONS

Non-invasive mapping of metastatic landing sites in PCa using WB-MRI/DWI shows that 28% of the mHNPC patients, and 52% of the mCRPC can be classified as oligometastatic, thus challenging the concept of metastatic targeted therapy. More than two thirds of metastatic patients have LN located outside the usually recommended targets of eLND and pelvic EBRT. Prophylactic or salvage treatments of these sole areas in patients with high-risk prostate cancer may not prevent the emergence of subsequent metastases. Prostate 76:1024-1033, 2016. © 2016 Wiley Periodicals, Inc.

JOURNAL CLUB: Identification of Bone Metastasis With Routine Prostate MRI: A Study of Patients With Newly Diagnosed Prostate Cancer

OBJECTIVE

The purpose of this study was to evaluate whether routine prostate MRI is adequate for detection of bone metastasis in patients with newly diagnosed prostate cancer.

MATERIALS AND METHODS

The study included 308 patients with newly diagnosed prostate cancer who underwent prostate MRI. Two radiologists categorized MRI findings as normal, metastasis, or equivocal. Histologic analysis or best valuable comparator based on comprehensive review of images and clinical follow-up studies were used as reference standards. Clinicopathologic variables and MRI findings were compared between patients with and those without bone metastasis by use of chi-square and t tests. The diagnostic performance of prostate MRI for detecting bone metastasis was assessed by ROC analysis. Subgroup analysis was performed for patients at high risk of bone metastasis.

RESULTS

Twenty-one (6.8%) patients had bone metastasis. They had significantly higher prostate-specific antigen levels (p = 0.015) and Gleason scores (p < 0.001) than those without bone metastasis. The diagnostic performance of MRI was as follows: sensitivity, 95.2%; specificity, 99-100%; positive predictive value, 86.9-100%; negative predictive value, 99.7%. For 119 patients at high risk of bone metastasis, these values were 95%, 100%, 100%, and 99%. Only 1 of the 21 (4.8%) patients had bone metastasis only in an area not explored with prostate MRI, that is, the thoracic spine.

CONCLUSION

The diagnostic performance of routine prostate MRI for identifying bone metastasis in patients with newly diagnosed prostate cancer was excellent.

Comparison of choline-PET/CT, MRI, SPECT, and bone scintigraphy in the diagnosis of bone metastases in patients with prostate cancer: a meta-analysis

Published data on the diagnosis of bone metastases of prostate cancer are conflicting and heterogeneous. We performed a comprehensive meta-analysis to compare the diagnostic performance of choline-PET/CT, MRI, bone SPECT, and bone scintigraphy (BS) in detecting bone metastases in parents with prostate cancer. Pooled sensitivity, specificity, and diagnostic odds ratios (DOR) were calculated both on a per-patient basis and on a per-lesion basis. Summary receiver operating characteristic (SROC) curves were also drawn to obtain the area under curve (AUC) and Q* value. Sixteen articles consisting of 27 studies were included in the analysis. On a per-patient basis, the pooled sensitivities by using choline PET/CT, MRI, and BS were 0.91 [95% confidence interval (CI): 0.83-0.96], 0.97 (95% CI: 0.91-0.99), 0.79 (95% CI: 0.73-0.83), respectively. The pooled specificities for detection of bone metastases using choline PET/CT, MRI, and BS, were 0.99 (95% CI: 0.93-1.00), 0.95 (95% CI: 0.90-0.97), and 0.82 (95% CI: 0.78-0.85), respectively. On a per-lesion basis, the pooled sensitivities of choline PET/CT, bone SPECT, and BS were 0.84 (95% CI: 0.81-0.87), 0.90 (95% CI: 0.86-0.93), 0.59 (95% CI: 0.55-0.63), respectively. The pooled specificities were 0.93 (95% CI: 0.89-0.96) for choline PET/CT, 0.85 (95% CI: 0.80-0.90) for bone SPECT, and 0.75 (95% CI: 0.71-0.79) for BS. This meta-analysis indicated that MRI was better than choline PET/CT and BS on a per-patient basis. On a per-lesion analysis, choline PET/CT with the highest DOR and Q* was better than bone SPECT and BS for detecting bone metastases from prostate cancer.

Monitoring the response of bone metastases to treatment with Magnetic Resonance Imaging and nuclear medicine techniques: a review and position statement by the European Organisation for Research and Treatment of Cancer imaging group

Assessment of the response to treatment of metastases is crucial in daily oncological practice and clinical trials. For soft tissue metastases, this is done using computed tomography (CT), Magnetic Resonance Imaging (MRI) or Positron Emission Tomography (PET) using validated response evaluation criteria. Bone metastases, which frequently represent the only site of metastases, are an exception in response assessment systems, because of the nature of the fixed bony defects, their complexity, which ranges from sclerotic to osteolytic and because of the lack of sensitivity, specificity and spatial resolution of the previously available bone imaging methods, mainly bone scintigraphy. Techniques such as MRI and PET are able to detect the early infiltration of the bone marrow by cancer, and to quantify this infiltration using morphologic images, quantitative parameters and functional approaches. This paper highlights the most recent developments of MRI and PET, showing how they enable early detection of bone lesions and monitoring of their response. It reviews current knowledge, puts the different techniques into perspective, in terms of indications, strengths, weaknesses and complementarity, and finally proposes recommendations for the choice of the most adequate imaging technique.

One-step TNM staging of high-risk prostate cancer using magnetic resonance imaging (MRI): toward an upfront simplified "all-in-one" imaging approach?

BACKGROUND

Multiparametric magnetic resonance imaging (mpMRI) is the standard for local prostate cancer (PCa) staging. Whole-body MRI (wbMRI) has shown capabilities for metastatic screening. This study assesses the feasibility and value of an all-in-one AJCC TNM staging of PCa during a unique MRI session combining mpMRI and wbMRI.

METHODS

Thirty consecutive patients with "high-risk" PCa prospectively underwent mpMRI of the prostate and wbMRI, in addition to (99m) Tc bone scan (BS), completed with standard X-rays (±TXR) and contrast enhanced CT for distant staging. For the statistical analysis, a "best valuable comparator" (BVC) combining a panel review of all available baseline and follow-up imaging, biological, and clinical data was used to adjudicate lymph node and bone metastatic status.

RESULTS

Prostate mpMRI was analyzed using ESUR guidelines. Sensitivity of BS ± TXR combined with CT and of wbMRI for detecting metastases (bones or nodes) was 85% and 100%, respectively, and specificity was 88% and 100%, respectively. For the overall staging of the patients as being either N0M0 or having disease extension beyond the prostate, wbMRI was superior to the combination of BS and CT (improvement in all ROC characteristics and of AUC by 13.6% (95% CI: +0.7% to +26.5%, P = 0.039)). The main limitation is the limited number of patients.

CONCLUSIONS

AJCC M and N staging using wbMRI is feasible during the same imaging session as mpMRI performed for T staging, in less then one hour. wbMRI outperforms BS ± TXR and abdomino-pelvic CT work up for discriminating subsets of patients with or without distant spread of the cancer.