|
 
 |
| REVIEW ARTICLE |
|
| Year : 2021 | Volume
: 23
| Issue : 1 | Page : 1-10 |
|
Contemporary role of multiparametric magnetic resonance imaging in the management of prostate cancer
Idorenyin C Akpayak1, Kenis S Felangu2, Lemech E Nabasu3
1 Division of Urology, Surgery Department, Jos University Teaching Hospital, Jos, Nigeria
2 Radiology Department, Nisa Hospital, Abuja, Nigeria
3 Surgery Department, Nisa Hospital, Abuja, Nigeria
| Date of Submission | 23-Apr-2020 |
| Date of Decision | 25-Jun-2020 |
| Date of Acceptance | 29-Jun-2020 |
| Date of Web Publication | 28-Apr-2021 |
Correspondence Address:
Dr. Idorenyin C Akpayak
Division of Urology, Surgery Department, Jos University Teaching Hospital, Jos
Nigeria
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jomt.jomt_22_20
Background: In contemporary practice, multiparametric magnetic resonance imaging has become a useful tool to differentiate between prostate cancers of high and low aggressiveness, reduce misdiagnosis, overdiagnosis and therefore overtreatment. This article aims to provide a concise review of the multiparametric magnetic resonance imaging (mpMRI) of the prostate, its interpretation and its role in the current management of prostate cancer. Methods: his was a narrative review of the contemporary role of the mpMRI in the management of prostate cancer. The databases and journals in urology and radiology were searched for relevant and contemporary existing literature on the subject. Results: We reviewed the technical aspects of the mpMRI of the prostate, describing the T-2 weighted imaging, the diffusion weighted imaging and the dynamic contrast enhanced imaging as well as the magnetic resonance spectroscopy of the prostate. We also reviewed the current interpretation and reporting of the mpMRI of the prostate using the PI-RADS; as well as the contemporary role of the mpMRI in prostate cancer management. Conclusion: The mpMRI is technologically robust and fast evolving imaging modality that has become a significant tool in the diagnosis, staging and treatment planning of prostate cancer.
Keywords: multiparametric MRI, PI-RADS, prostate cancer
How to cite this article:
Akpayak IC, Felangu KS, Nabasu LE. Contemporary role of multiparametric magnetic resonance imaging in the management of prostate cancer. J Med Trop 2021;23:1-10 |
How to cite this URL:
Akpayak IC, Felangu KS, Nabasu LE. Contemporary role of multiparametric magnetic resonance imaging in the management of prostate cancer. J Med Trop [serial online] 2021 [cited 2023 Mar 23];23:1-10. Available from: https://www.jmedtropics.org/text.asp?2021/23/1/1/314844 |
| Introduction | |  |
Prostate cancer is the most commonly diagnosed cancer in men globally.[1] It is commoner in blacks and the commonest cancer in Nigerian men.[2],[3] Also, in Nigeria, prostate cancer is the leading cause of cancer death in men.[2]
Traditionally, the diagnosis of prostatic carcinoma is based on clinical presentation of the patient, digital rectal examination (DRE), evaluation of prostate specific antigen (PSA) followed by TRUS-guided prostate biopsy.[4],[5] However, the DRE has very low sensitivity and can only detect tumours with volume over 0.2 ml.[6] Also, the level of PSA rises with prostate cancer, benign prostatic hyperplasia (BPH), prostatitis, prostatic infarct and prostatic injury. Therefore, PSA as a biomarker is organ specific but not disease specific.[7],[8]
The 12-core systematic TRUS-guided prostate biopsy is the current gold standard technique in obtaining specimen for histological diagnosis of prostate cancer.[9] The technique however is affected by sampling errors and fails in occasions to detect clinically significant prostate cancer.[10],[11]
These shortcomings put together may lead to prostate cancer misdiagnosis and inaccurate risk assessment of the cancer. Prostate cancer screening carried out with the hope of making early diagnosis depends heavily on the above traditional diagnostic process and therefore also suffers prostate cancer misdiagnosis and additionally over-diagnosis and therefore overtreatment.[12],[13]
Magnetic resonance imaging (MRI) as an imaging modality demonstrates both the anatomy and the pathological lesions based on the principle that atomic nuclei in a strong magnetic field absorbs pulses of radiofrequency energy and emit them as radiowaves that can be received, then reconstructed into 2D images.[14] The technical improvements and introduction of functional parameters have improved the accuracy of the MRI.[15]
In contemporary practice, multiparametric magnetic resonance imaging (mpMRI) has become a useful tool to differentiate between prostate cancers of high and low aggressiveness, reduce misdiagnosis, overdiagnosis and therefore overtreatment.[16],[17] Currently, MRI has made a tremendous impact in the management of prostate cancer by using a combination of morphologic and functional sequences which allow the analysis of aggressiveness of the cancer.[18] This article aims to provide a concise review of the mpMRI of the prostate, its interpretation and its role in the current management of prostate cancer.
| Methods | | |
This was a narrative review of the contemporary role of the mpMRI in the management of prostate cancer. The database was searched for recent information on the contemporary role of multiparametric MRI of the prostate. The data base searched included MEDLINE, Excerpta Medica Database (EMBASE), google scholar, individual urology and radiology journals. The search terms included, “multiparametric MRI of the prostate”, “prostate cancer”, “PI-RADS score”, “interpretation of mpMRI of the prostate”, role of mpMRI of the prostate”, “indications of mpMRI of the prostate”. We included relevant images from our hospital mpMRI of the prostate data base. The second author made the interpretation of all the images.
The search were limited to English language articles from 1995 to 2020. We included studies and articles that focused on the technical aspects, the interpretation and the role of the mpMRI of the prostate.
| Overview of the technical aspects of multiparametric magnetic resonance imaging of the prostate | | |
Imaging the prostate with MRI was first described in the mid-1980s.[19] Low-field magnets and body coil technology used at that time resulted in low spatial resolution of the prostatic images. With consistent technological improvements, the MRI of the prostate has become unique and a go-to imaging modality for the visualization and characterization of lesions of the prostate.[15]
The multiparametric MRI (mpMRI) of the prostate requires the acquisition and interpretation of the prostate images from the pulse sequences of the MRI, including: the T-2 weighted (T2W) imaging, the diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging, with or without magnetic resonance spectroscopy (MRS).[20] Each of the MRI technique has advantages and draw backs. Therefore, satisfactory interpretation is achieved by combinations of these sequences.
The functional MRI techniques (MRSI+, DWI and DCEI) add value to the anatomic (T2WI) MRI (the workhorse of the mpMRI of the prostate) in the detection, localization, grading and staging of prostate cancer.[21] When T2WI and DWI are of diagnostic quality, DCEI plays a minor role in determining the prostate Imaging-Reporting and Data system (PI-RADS) assessment category of lesions of the prostate.[22]
Both 1.5T and 3T MRI machines are currently used for mpMRI of the prostate. The 3T MRI machine is becoming increasingly available and is generally preferred due to higher signal-to-noise ratio (SNR) with resultant better image resolution.[23] Beyond the strength of the magnetic field, many technical factors have influence on the SNR and spatial resolution of the mpMRI of the prostate. These include the receiver bandwidth, the coil design, and the efficiency of the radio frequency (RF) coil.[24]
The contemporary 1.5T and 3T MR scanners employ external array of coil elements capable of achieving adequate SNR.[25] When integrated with external array coils, the endorectal coil (ERC) has been thought to increase the SNR.[26] However, the drawback of the ERC is that it may increase the cost and time of the examination, deform the prostate gland and introduce artefacts. It may also increase patient discomfort and reduce acceptability of the mpMRI.[27] With current family of 1.5 and 3T MR scanners, ERC has not been found to be essential in achieving satisfactory image resolution of the prostate.[28]
T-2 weighted imaging
The T-2 weighted imaging is the mainstay of the mpMRI of the prostate and it is traditionally carried out in axial, sagittal and coronal planes.[29] With the fast-spine echo (FSE), high SNR allows the T2W sequence to provide high spatial resolution of the zonal anatomy of the prostate gland.[20] With this sequence, it is frequently possible to differentiate the high signal intensity PZ from the TZ [Figure 1]A and 1B. | Figure 1 A: Axial T2WI of the prostate showing the PZ and TZ with a 1.5T MR scanner. B. The image on the left is a coronal view of the T2WI. The PZ in the axial view is homogenously hypertintense. While the TZ is heterogeneously hypointense
Click here to view |
In the T2WI, the prostate cancer appears as area of low signal intensity within the high intensity signal of the peripheral zone (PZ).[30] Also, it has been found that the higher the Gleason score in histological evaluation, the lower the signal intensity on the T2WI of the mpMRI.[31]
The limitation of the T2WI is the lack of specificity for areas of low signal intensity in the PZ of the prostate as this may represent chronic prostatitis, post-prostatitis scars, atrophy and post-biopsy haemorrhage.[32] These conditions may be correctly identified as benign on the basis of their wedged-shaped or diffuse appearance on T2WI. Yet, their presence makes assessment of PZ on T2WI difficult. Therefore where possible, mpMRI of patients suspected of having prostate cancer should be delayed 8 weeks after prostate biopsy or should be repeated after six month of a suspected prostatitis to allow reduction of artefacts due to post-biopsy haemorrhage or prostate inflammation.[33],[34] The use of T2WI is also limited in the transition zone (TZ) of the prostate where benign prostatic hyperplasia appearance is similar to that of prostate cancer focus.[35]
Diffusion weighted imaging
Diffusion weighted Imaging (DWI) is an essential sequence for the detection and prediction of prostate cancer aggressiveness.[36] The Diffusion weighted images are produced by taking advantage of the diffusion properties of proton in water to produce image contrast.[22] The apparent diffusion coefficient (ADC) is obtained from DWI and signifies the movement of water molecules within the interpluse time.[37]
The normal prostatic tissue, including PZ is rich in water and tubular structures which allows extensive diffusion of water molecules within the gland. Consequently, the ADC in the normal prostate gland is high.[38] When prostate cancer develops, the normal tubular structure is replaced and the gland becomes higher in cellular density. The ADC then becomes lower at the tumour focus compared to the normal surrounding tissues. With lower ADC compared to the surrounding healthy prostatic tissue, the prostate cancer foci appear hypointense on ADC maps but hyperintense on the diffusion weighted DW), at high b-value image [Figure 2]A and 2B.[39] The limitation of the DWI is that it has poor spatial resolution, it is susceptible to motion artefacts as well as magnetic inhomogeneity, and therefore not be used for local staging.[40] As a result, DW images need to be correlated with T2W images. | Figure 2 A and 2B: The ADC and DWI of the T2 images showing cancer focus in PZ demonstrating significant restriction of diffusion; markedly low on ADC. D. Very high signal on high b-value DW
Click here to view |
Dynamic contrast-enhanced imaging
Dynamic contrast-enhanced imaging (DCEI) consists of series of T1-weigheted sequences of the entire prostate gland before and after rapid bolus injection of 3-4 ml/s of gadolinium contrast agent.[41],[42] It asses signal intensity changes to detect areas with pharmacokinetic features seen in cancer angiogenesis. Where there is prostate cancer, the focus enhances faster and to a greater extent compared to the normal prostatic tissues. The focus also shows earlier contrast washout [Figure 3]A and 3B.[41],[42] | Figure 3 A and 3B: Axial T1 MRI images at the level of the prostate for pre(Image to the left, Figure 3A) and post(Image to the right, Figure 3B) contrast study. The contrast series shows contrast enhancement on right peripheral zone of the prostate where the cancerous focus is
Click here to view |
In radiologic practice, post-processing of DCEI to generate colour overlay maps on T2WI are used to depict signal intensity. The colour overlay images are semi-quantitative data that represents the concentration of gadolinium in tissue with time (the gadolinium concentration-time curve).[43] Despite these efforts, the heterogeneity in the enhancement characteristics of prostate cancer adds to poor image interpretations.
The drawback of DCEI is that the visual and subjective comparison of preconstrast and postcontrast images in the background of hypervascularised tissues of the prostate can be challenging.[44] Also, in DCE imaging, the features of BPH, chronic prostatitis and prostate cancer can also overlap.[44] Therefore, currently there is little evidence to support its routine use.
Magnetic resonance spectroscopy
This is a functional technique in which the spectral profiles reflecting resonance frequencies that are unique for protons in different metabolites (choline, citrate and creatinine) are measured. The choline and creatinine signals are increased in prostate cancer compared to the normal tissues of the prostate, while those of citrate decrease in prostate cancer compared to the normal prostatic tissue.[45] A (choline + creatinine)/citrate ratio >0.86 or citrate/(choline + creatinine) ratio of <1.4 was found to be specific marker for prostate cancer.[45]
Currently, magnetic resonance spectroscopy (MRS) is not routinely included in mpMRI of the prostate because of the long time required to acquire the data, as well as the experience and the expertise required to interpret the images. With new technological advancements, the robustness of MRS will further increase and it would likely become a routine part of mpMRI of the prostate.[46]
| INTERPRETATION AND REPORTING OF MULTIPARAMETRIC MAGNETIC RESONANCE IMAGING (PI-RADS CATEGORY) | | |
The reporting system used for mpMRI of the prostate has changed overtime in the bid to reduce inter-reader errors and disagreement as well as decrease the gap between differently skilled radiologists and improve the communication between radiologists and urologists. To achieve this purpose, the Prostate Imaging-Reporting and Data System version1 (PI-RADS vs 1) was developed in 2012 by the European Society of Urological Radiology (ESUR).[47] This was the first attempt to standardize prostate mpMRI reporting. The PI-RADS v1 was complex and a time consuming scoring system and therefore had poor reproducibility.[48]
PI-RADS v 2 was introduced in 2014 in an attempt to overcome the limitations of PI-RADS v 1 by the joint steering committee, formed by the ESUR, the American College of Radiology (ACR) and the AdMeTech foundation.[22] The PI-RADS vs2 assessment uses a 5-point scale [Table 1] and [Table 2][29] based on the likelihood (probability) that a combination of mpMRI of the prostate findings on T2WI, DWI and the DCEI correlates with presence of a clinically significant prostate cancer for each location in the gland. A detected focus is scored separately by the PI-RADS assessment on the different MRI techniques. Then, they are combined to give overall assessment category score to quantify the likelihood of the focus being clinically significant prostate cancer. | Table 2: PI-RADS Assessment of high b-value DWI/ADC-map for both PZ and TZ[29]
Click here to view |
More recently, an updated version of PI-RADS v 2, the PI-RADS version 2.1 aimed to further simplify the assessment and reporting, as well as to reduce interpretation variability of the mpMRI of the prostate.[49] The PI-RADS v 2.1 emphasizes the dominant role of DWI as the parameter for any suspicious lesion(s) found in the PZ and T2WI, in the TZ. For instance, if DWI score is say 4 in PZ, and T2WI score is 2, then the overall PI-RADS assessment category should be 4. On the other hand, in TZ, T2WI is the primary (dominant) sequence. So, if T2WI score is 4 in the TZ lesion, and DWI PI-RADS score is say 2, then the PI-RADS assessment category should be 4.[49]
DCEI scores are a binary assessment, and serves to reduce the number of equivocal lesions (PI-RADS 3 lesions). Its role is limited to upgrading DCEI-positive lesion(s) in the PZ from PI-RADS category 3 to 4.[48] In PI-RADS v 2.1 assessment system, a “positive” DCE (DCE +) MRI lesion is one that there is focal enhancement, earlier or contemporaneous; that corresponds to a finding on TW2 and/or DWI. A “negative” DCE (DCE −) MRI lesion is one that either does not enhance early compared to surrounding prostate or enhances diffusely so that margins of enhancing areas do not correspond to findings on T2WI and/or DWI.[49],[50] Notably, many authors believe that the added value of DCE over and above the combination of T2WI and DWI is modest. Therefore, the role of DCE in determination of PI-RADS vs 2.1 assessment category is secondary to T2WI and DWI.[51]
The role of multiparameteric MRI of the prostate
The different clinical scenarios in which mpMRI of the prostate play important roles are:
1) To detect prostate cancer and guide patient selection for prostate biopsy:
The most important function of mpMRI of the prostate is the localization of the prostate cancer.[52],[53],[54] Multiparametric MRI is currently used to detect clinically significant prostate cancer.[18] In PI-RADS v 2.1, clinically significant cancer is defined on histology/pathology as cancer with Gleason score ≥7, and/or volume ≥0.5ml, and/or extraprostatic extension (EPE).[22] The PI-RADS vs 2.1 does not however, make recommendations for the management as that takes into account other factors like clinical history, patient PSA and clinical examination findings.[22]
The mpMRI also facilitates MRI guided biopsy (MRGB) of the clinically significant prostate cancer foci. All MRGB strategies (cognitive MRI-ultrasound fusion, MRI-TRUS fusion and in-bore MRGB) requires that information from mpMRI is analysed and used to target suspicious focus.
Many studies have demonstrated that MRI-targeted prostate biopsy is better than the systematic biopsy in the diagnosis of clinically significant prostate cancer.[55],[56],[57] Consensus on selecting patients for biopsy, has not been fully agreed upon. For instance, the EAU guideline on prostate cancer suggests that mpMRI could be used in the following clinical scenarios:- To increase the rate of detection of prostate cancer by addition of targeted biopsy to systematic biopsy in patients in whom mpMRI detects a clinically significant prostate cancer. b) To guide when to proceed on systematic prostate biopsy where mpMRI of the prostate is negative and PSA is high. c) To guide when not to proceed on systematic prostate biopsy where the mpMRI is negative.
- To facilitate only targeted prostate biopsy.[46]
Ahoot et al.[58] colleagues in a more recent study: MRI-targeted, systematic and combined biopsy for the prostate cancer diagnosis took a critical look at what prostate biopsy technique could yield the best outcome. They found that combine (systematic and targeted) biopsy leads to an increase in the number of cancer diagnosis and improves likelihood that the biopsy findings are predictive of the true pathologic nature of the patient’s disease.
In instances where patients had previous negative systematic prostate biopsy, mpMRI is carried out to identify the clinically significant prostate cancer foci that might have been missed and proceed to target biopsy of the foci.
2) To guide patients selection for active surveillance:
Up to 40% of all men over 50 have been found to have lower risk prostate cancer.[59] Over the last decade, active surveillance (AS) has emerged as a treatment option for men with early-stage disease, low-risk prostate cancer.[60] However, the choice of AS is riddled with many uncertainties including optimal patient selection and strategic triggers for intervention.[61]
Epstein criteria has been the most popular tool to identify patients with clinically insignificant prostate cancer and thus eligible for AS.[62] The criteria specify that men should have no more than 2 cores involved, with less than 50% of any one core involved, and a PSA density of less than 0.15ng/ml.
Recruiting prostate cancer patients that are suitable for AS is recently made possible by mpMRI due to its significant ability to discern clinically significant prostate cancer from the low risk ones. Almeida et al.[63] in assessing the role of mpMRI and PI-RADS score in patients with prostate cancer concluded that mpMRI in addition to clinical criteria helps in the selection of patients for AS.
3) To guide staging and treatment of prostate cancer:
The local staging of prostate cancer has been made possible by T2WI.[64] Typically, the PZ tumour appears as hypointense foci [Figure 4]. Once such lesion is detected, evaluation of the tumour is required. The most important overall assessment is whether the tumour is confined to the gland (T≤2) or has extended beyond the gland (≥T3). This could detect the extraprostatic extension, extension to seminal vesicle and the bladder neck. The feature of seminal vesicle (SV) invasion include focal or diffuse low T2W signal intensity [Figure 5], abnormal contrast enhancement within the SV, restricted diffusion on DWI/ADC map and obliteration of the angle between the base of the prostate and the SV.[15] | Figure 4: Axial T2 image at the level of the seminal vesicle, tumour (hypointense focus) is seen to extend to the medial left seminal vesicle, making the stage to be T3b prostate cancer
Click here to view |
 | Figure 5: Axial T2 image at the level of the seminal vesicle, tumour (hypointense focus) is seen to extend to the medial left seminal vesicle, making the stage to be T3b prostate cancer
Click here to view |
In contemporary practice, multiparametric magnetic resonance imaging has become a useful tool to differentiate between prostate cancers of high and low aggressiveness, reduce misdiagnosis, overdiagnosis and therefore overtreatment. This article aims to provide a concise review of the multiparametric magnetic resonance imaging (mpMRI) of the prostate, its interpretation and its role in the current management of prostate cancer.
The determination of microscopic extraprostatic extension is however more difficult with mpMRI. Nodal staging is possible since the regional lymph nodes are in the field of view (FOV) of the examination. It is also possible to see metastases to the pelvic bone or head of femur on routine mpMRI of the prostate images [Figure 6]. | Figure 6: Axial T2 and DWI images at different level of the pelvis, tumour has infiltrated mesorectal facia and bladder (T4) there are also multiple mesorectal and pelvic node. On the DWI bone deposit are appreciated on the acetabulum having similar signal with the tumour
Click here to view |
Multiparametric MRI of the prostate has also found its usefulness in the pre-operation choice of the nerve sparing radical prostatectomy. The use of mpMRI to locate the tumour, determine its clinical aggressiveness and the clinical stage, has made it useful in treatment planning for both external beam radiotherapy and intensity-modulated radio-therapy (IMRT).
| Conclusion | | |
The mpMRI is fascinating and fast evolving imaging modality that has become a significant tool in the diagnosis, staging and treatment planning of prostate cancer.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
| References | | |
| 1. | Fitzmaurice C, Dicker D, Pain A, Hamavid H, Moradi-Lakeh M, Maclntyre XX et al. The global burden of cancers 2013;JAMA Oncol 2015;505-27.  |
| 2. | Ogunbiyi JO, Shittu OB. Increased incidence of prostate cancer in Nigerians. J Natl Med Assoc 1999;91:159-64. |
| 3. | Mohammed AZ, Edino ST, Ochicha AA. Cancer in Nigeria: a 10 year analysis of the Kano cancer registry. Niger J Med 2008;17:280-4. |
| 4. | Osegbe DN. Prostate cancer in Nigerians: facts and nonfacts. J Urol 1997;157:1340-3. |
| 5. | Maltaga BR, Eskew LA, McCullough DL. Prostate biopsy: indications and technique. J Urol 2003;169: 12-19. |
| 6. | Catalona WJ, Richie JP, Ahmann FR, Hudson MA, Scardino PT, Flanigan RC et al. Comparison of digital rectal examination and serum prostate specific antigen in the early detection of prostate cancer: results of multicenter and clinical trial of 6,630 men. J Urol 1994;151:1283-90. |
| 7. | Hoffman RM. Clinical practice. Screening for prostate cancer. N Engl J Med 2011;365:2013-19. |
| 8. | Schroder FH, Carter HB, Wolters T, Berg RC, Gosselaar C, Bangma C et al. Early detection of prostate cancer in 2007. Part 1: PSA and PSA kinetics. Eur Urol 2008;53:468-77. |
| 9. | Mottet N, Bellmunt J, Bolla M, Briers E, Cumberbatch MG, Santis M et al. EAU-SIOG guideline on prostate cancer. Part 1: screening, diagnosis and local treatment with curative intent. Eur Urol 2017;71:618-29. |
| 10. | Halpern EJ, Strup SE. Using gray-scale and colour and power Doppler sonography to detect prostate cancer. AJR Am J Roentgenol 2000;174:623-7. |
| 11. | Pinthus JH, Witkos M, Fleshner NE, Sweet J, Evans A, Jewett MA et al. Prostate cancers scored as Gleason 6 on prostate biopsy are frequently Gleason 7 tumours at radical prostatectomy: implication on outcome. J Urol 2006;176:979-84. |
| 12. | Schroder FH, Hugosson J, Roobol MJ, Tammela TL, Ciatto S, Nelen V et al. Screening and prostate cancer mortality in a randomized European study. N Engl J Med 2009;360:1320-8. |
| 13. | Loeb S, Bjurlin MA, Nicholson J, Tammela TL, Penson DF, Carter HB et al. Overdiagnosis and overtreatment of prostate cancer. Eur Urol 2014;65:1046-55. |
| 14. | Chavhan G. Basic principles. In: Chavhan G (author). MRI made easy. New Delhi: Jaypee Brothers medical publishers. 2013 1-7. |
| 15. | Thompson J, Lawrentschuk N, Frydenberg M, Thompson L, Sticker P. (on behalf of USANZ). The role of magnetic resonance imaging in the diagnosis and management of prostate cancer. BJU Int 2013;112:6-20. |
| 16. | Cornud F, Delongchamps NB, Mozer P, Beuvon F, Schull A, Muradyan N et al. Value of multiparametric MRI in the work-up of prostate cancer. Curr Urol Rep 2012;13:82-92. |
| 17. | Kurhanwicz J, Vigneron D, Carrol P, Coakley F. Multiparametric magnet resonance imaging in prostate cancer: present and future. Curr Opin Urol 2008;18:71-77. |
| 18. | Giganti F, Rosenkrantz AB, Villeirs G, Panebianco V, Stabile A, Emberton M et al. Evolution of MRI of the prostate: the past, the present and the future. Am J. Roentgenol 2019;213:384-96. |
| 19. | Poon PY, Mcallum RN, Henkelman MM, Bronskill MJ, Sutcliffe SB, Jewett MA et al. Magnetic resonance imaging of the prostate. Radiology 1985;154:143-9. |
| 20. | Hedge JV, Mulkern RV, Panych LP, Fennessy FM, Fedorov A, Maier SE et al. Multiparametric MRI of prostate cancer: an update on state-of-the-art techniques and their performances in detecting and localizing prostate cancer. J Magn Reson Imaging 2013;57:1035-54. |
| 21. | Puech P, Huglo G, Petyt G, Lemaitre L, Villers A. Imaging of organ-confined prostate cancer: functional ultrasound, MRI and PET/computed tomography. Curr Opin Urol 2009;19:168-76. |
| 22. | Weinreb JC, Barentsz JO, Choyke PL, Cornud F, Haider MA, Macura KJ et al. PI-RADS prostate imaging-reporting and data system: 2015, version 2. Eur Urol 2016;69:16-40. |
| 23. | Rouviere O, Hartman RP, Lyonnet D. Prostate MR imaging at high-filed strength: evolution or revolution? Eur Radiol 2006;16:276-84. |
| 24. | Kathiravan S, Kanakaraj XX. A review on potential issues and challenges in MRimaging. Scientific World Journal 2013;2013:78371.doi:10.1155/2013/783715.eCollection2013 |
| 25. | Hricak H, White S, Vigneron D, Kurhanewicz J, Kosco A, Levin D et al. Carcinoma of the prostate gland: MR imaging with pelvic phased-array coils versus integrated endorectal-pelvic phased-array coils. Radiology 1994;193:703-6. |
| 26. | Heijmink SW, Futterer JJ, Hambrock T, Takahashi S, Scheenen TW, Huisman HJ et al. Prostate cancer: body-array versus endo-rectal coil MR imaging at 3T − comparison of image quality, localization, and staging performance. Radiology 2007;244:184-95. |
| 27. | Husband JE, Padhani AR, MacVicar AD, Reveil P. Magnetic resonance imaging of prostate cancer: comparison of image quality using endorectal and pelvic phased array coils. Clin Radiol 1998;53:673-81. |
| 28. | Zelhof B, Lowry M, Rodrigues G, Kraus S, Turnbull L. Description of magnetic resonance imaging-derived enhancement variables in pathologically confirmed prostate cancer and normal peripheral zone region. BJU Int 2009;104:621-7. |
| 29. | Costa DN, Pedrosa I, Roehrborn C, Rofsky NM. Multiparametric magnetic resonance imaging of the prostate: technical aspects and role in clinical management. Top Magn Reson Imaging 2014;23:243-57. |
| 30. | Hoeks CM, Barentsz JO, Hambrock T, Yakar D, Somford DM, Heijmink WT et al. Prostate cancer multiparametric MR imaging for detection, localization and staging. Radiology 2011;261:46-66. |
| 31. | Wang L, Mazaheri Y, Zhang J, Ishill NM, Kuroiwa K, Hricak H. Assessement of biologic aggressiveness of prostate cancer: correlation of MR signal intensity with Gleason grade after radical prostatectomy. Radiology 2008;246:168-76. |
| 32. | Kirkham AP, Emberton M, Allen C. How good is MRI at detecting and characterizing cancer within the prostate? Eur Urol 2006;50:1163-74. |
| 33. | Qayyum A, Coakley FV, Lu Y, Olpin JD, Wu L, Yeh BM et al. Organ-confined prostate cancer: effect of prior transrectal biopsy on endorectal MRI and MR spectroscopic imaging. AJR Am J Roentgenol 2004;183:1079-83. |
| 34. | Andrew B, Rosenkrantz XX, Taneja SS. Radiologist beware: ten pitfalls that confound the interpretation of multiparametric prostate MRI. AJR Am J Roentgenol 2104;202:109-20. |
| 35. | Akin O, Sala E, Moskowitz CS, Kuroiwa K, Ishill NM, Scardino PT et al. Transition zone prostate cancers: features, detection, localization, and staging at endorectal MR imaging. Radiology 2006;239:784-92. |
| 36. | Engels RR, Israel B, Padhani AR, Barentsz JO. Multiparametric magnetic resonance imaging for the detection of clinically significant prostate cancer: what urologists need to know. Part 1: acquisition. Eur Urol 2020;77:457-68. |
| 37. | Jacobs MA, Ouwerkerk R, Petrowski K, Macura KJ. Diffusion-weighted imaging with apparent diffusion coefficient mapping and spectroscopy in prostate cancer. Top in Magn Reson Imaging 2008;19:261-72. |
| 38. | Somford DM, Futterer JJ, Hambrock T, Barentsz JO et al. Diffusion and perfusion MR imaging of the prostate. Magn Reson Imaging Clin N Am 2008;16:685-95. |
| 39. | Gibbs P, Tozer DJ, Liney GP, Turnbull LW. Comparison of quantitative T2 mapping and diffusion-weighted imaging in normal and pathologic prostate. Magn Resonance Med 2001;46:1054-8. |
| 40. | Scherrer B, Gholipour A, Warfield SK. Super-resolution reconstruction to increase the spatial resolution of diffusion-weighted images from orthogonal anisotropic acquisitions. Med Image Annal 2012;16:1465-76. |
| 41. | Barentsz JO, Engelbrecht M, Jager GJ, Witjes JA, de larosette J, Sanden BP et al. Fast dynamic gadolinium-enhanced MR imaging of urinary bladder and prostate cancer. J Magn Reson Imaging 1999;10:295-304. |
| 42. | Engelbrecht MR, Huisman HJ, Laheij RJ, Jager GJ, Leenders JL, Hulsbergen-Van De Kaa CA et al. Discrimination of prostate cancer from normal peripheral zone and central gland tissue by using dynamic contrast-enhanced MR imaging. Radiology 2003;229:248-54. |
| 43. | Alonzi R, Padhari AR, Allen C. Dynamic contrast-enhanced MRI in prostate cancer. Eur J Radiol 2007;63:335-0. |
| 44. | Jager GJ, Ruijter ET, van de kaa CA, de la Rosette XX, Oosterhof GO, Thornbury JR et al. Local staging of prostate cancer with endorectal MR imaging: correlation with histopathology. AJR AmJ Roentgenol 1996;166:845-2. |
| 45. | Cornel EB, Smits GA, Oosterhof GO, Karthaus HF, Deburyne FM, Schalken JA et al. Characterization of prostate cancer, benign prostatic hyperplasia and normal prostate by in vitro 1H and 31P magnetic resonance spectroscopy. J Urol 1993;150:2019-24. |
| 46. | Weinreb JC, Blume JD, Coarkly FV, Wheeler TM, Cormack JB, Sotto CK et al. Prostate cancer: sextant localization at MR imaging and MR spectroscopic imaging before prostatectomy − results of ACRIN prospective multi-institutional clinicopathologic study. Radiology 2009;251:122-33. |
| 47. | Barentsz JO, Richenberg J, Clements R, Choyke P, Verma S, Villiers G et al. ESUR prostate MR guidelines 2012. Eur Radiol 2012;22:746-57. |
| 48. | Stabile A, Giganti F, Rosenkrantz AB, Taneja SS, Villeirs G, Gill IS et al. Multiparameteric MRI for prostate cancer diagnosis: current status and future directions. Nature Reviews 2019;19:212-4. |
| 49. | Turkbey B, Rosenkrantz AB, Haider MA, Padhani AR, Villeirs G, Macura KJ et al. Prostate Imaging Reporting and Data System version 2.1: 2019 update of Prostate Imaging Reporting and Data System version 2. Eur Urol 2019;76:340-51. |
| 50. | Brentsz JO, Weinreb JC, Verma S, Thoeny HC, Tempany CM, Shtern F et al. Synopsis of the PI-RADS v 2 guidelines for multiparametric prostate magnetic resonance imaging and recommendations for use. Eur Urol 2016;69:41-49. |
| 51. | Israel B, Leest M, Sedelaar M, Padhani AR, Zamecnik P, Barentsz JO. Multiparametric magnetic resonance imaging for the detection of clinically significant prostate cancer: what urologists need to know. Part2: interpretation. Eur Urol 2020;77:469-80. |
| 52. | Sciarra A, Barentsz J, Bjartell A, Eastham J, Hricak H, Panebianco V et al. Advances in magnetic resonance imaging: how they are changing the management of prostate cancer. Eur Urol 2011;59:962-77. |
| 53. | Rastinehad AR, Baccala AA Jr, Chung PH, Proano JM, Kruecker J, Xu S et al. D’amico risk stratification correlates with degree of suspicion of prostate cancer on multiparametric magnetic resonance imaging. J Urol 2011;185:815-20. |
| 54. | Turkbey B, Mani H, Shah V, Rastinehad AR, Bernado M, Pohida T et al. Multiparametric 3T prostate magnetic resonance imaging to detect cancer: histopathological correlation using prostatectomy specimens processed in customized magnetic resonance imaging based molds. J Urol 2011;186:1818-24. |
| 55. | Ruhrup J, Preisser F, Theißen L, Wenzel M, Roos FC, Becker A et al. MRI-Fusion targeted vs. systematic prostate biopsy-how does the biopsy technique affect Gleason grade corcodance and upgrading after radical prostatectomy? Front Surg 2019 doi: 10.3389/fsurg.2019.00055. |
| 56. | Kasivisvanathan V, Rannikko AS, Borghi M, Panebianco V, Mynderse LA, Vaarala M et al. MRI-targeted or standard biopsy for prostate-cancer diagnosis. N Engl J Med 2018;378 |
| 57. | Siddiqui MM, Rais-Bahrami S, Turkbey B, George AK, Rothwax J, Shakir N et al. Comparison of MR/ultrasound fusion-guided biopsy with ultrasound-guided biopsy for the diagnosis of prostate cancer. JAMA 2005;313:390-7. |
| 58. | Johnson DC, Raman SS, Mirak SA, Kwan L, Bajgiran AM, Hsu W et al. Detection of individual prostate cancer foci via multiparametric magnetic resonance imaging. Eur Urol 2019;75:712-20. |
| 59. | Ahoot AR, Wilbur SE, Lebastchi S, Mehralivand PT, Gomella JB, Bloom J et al. MR-targeted, systematic and combined biopsy for prostate cancer diagnosis. N Engl J Med 2020;382:917-28. |
| 60. | Has GP, De; longchamps N, Brawley OW, Wang CY, De la Roza G. The worldwide epidemiology of prostate cancer: perspectives from autopsy studies. Can J Urol 2008;15:3866-71. |
| 61. | Klotz L. Active surveillance for prostate cancer: for whom? J Clin Oncol 2005;23:8165-9. |
| 62. | Harnden P, Naylor B, Shelley MD, Clements H, Coles B, Magon MD. The clinical management of patients with a small volume of prostate cancer on biopsy: what are the risks of progression? A systematic review and meta-analysis. Cancer 2008;112:971-81. |
| 63. | Epstein JI, Chan DW, Sokoll LJ, Walsh PC, Cox JL, Rittenhouse H et al. Nonpalpable stage T1c prostate cancer: prediction of insignificant disease using free/total prostate specific antigen levels and needle biopsy findings. J Urol 1998;160:2407-11. |
| 64. | Almeida GL, Petralia G, Ferro M, Ribas CA, Detti S, Jereczek-Fossa BA et al. Role of multi-parametric magnetic resonance image and PI-RADS score in patients with prostate cancer eligible for active surveillance according PRIAS criteria. Urol Int 2016;96:459-69. |
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
[Table 1], [Table 2]
|
Search Pubmed for