scholarly journals Hyperpolarized 15N-labeled, deuterated tris(2-pyridylmethyl)amine as an MRI sensor of freely available Zn2+

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Eul Hyun Suh ◽  
Jae Mo Park ◽  
Lloyd Lumata ◽  
A. Dean Sherry ◽  
Zoltan Kovacs

AbstractDynamic nuclear polarization (DNP) coupled with 15N magnetic resonance imaging (MRI) provides an opportunity to image quantitative levels of biologically important metal ions such as Zn2+, Mg2+ or Ca2+ using appropriately designed 15N enriched probes. For example, a Zn-specific probe could prove particularly valuable for imaging the tissue distribution of freely available Zn2+ ions, an important known metal ion biomarker in the pancreas, in prostate cancer, and in several neurodegenerative diseases. In the present study, we prepare the cell-permeable, 15N-enriched, d6-deuterated version of the well-known Zn2+ chelator, tris(2-pyridylmethyl)amine (TPA) and demonstrate that the polarized ligand had favorable T1 and linewidth characteristics for 15N MRI. Examples of how polarized TPA can be used to quantify freely available Zn2+ in homogenized human prostate tissue and intact cells are presented.

2021 ◽  
Vol 14 (3) ◽  
pp. 86-93
Author(s):  
R.A. Romanov ◽  
◽  
A.V. Koryakin ◽  
A.V. Sivkov ◽  
B.Ya. Alekseev ◽  
...  

Introduction. Significant improvement in the quality of visualization of the prostate using magnetic resonance imaging (MRI), as well as the development of technologies for virtual combination of MRI and ultrasound images opens new horizons in the diagnosis of prostate cancer. The introduction of the PI-RADS system has allowed the standardization of MRI findings, and the development of fusion biopsy systems seeks to make diagnostics more accurate and less operator-dependent. Materials and methods. In this literature review, we evaluate the effectiveness of various biopsy approaches and discuss the prospects for targeted biopsies. The search for publications was carried out in the databases PubMed, e-library, Web of Scince et al. For citation, 55 literature sources were selected that met the search criteria for the keywords, «prostate cancer», «biopsy», «MRI», «TRUS», «fusion». Results. Diagnosis of prostate cancer using MRI. Modern technologies for radiological diagnosis of prostate cancer using magnetic resonance imaging (MRI) are based on the standardized PI-RADS protocol, using different modes (T2, diffusion-weighted images and contrast enhancement), which provides the best visualization of tumor-suspicious nodes in the prostate gland, allowing determination of lesion localization and size for subsequent targeted biopsy. Options for performing a prostate biopsy to diagnose prostate cancer. A description of the methods and effectiveness of transrectal and transperineal biopsy under ultrasound guidance is carried out - due to the fact that ultrasound diagnostics of prostate cancer has a rather low sensitivity due to small differences in the ultrasound structure of normal and tumor tissue of the prostate, an extended template biopsy technique was proposed, which involves puncture of the prostate through a special lattice. It also describes the technology of fusion biopsy and also provides literature data comparing the diagnostic accuracy of standard TRUS and fusion prostate biopsy, as well as the importance of transrectal / transperineal access. Questions for further study. Given the desire to reduce the number of biopsies while maintaining or even increasing the accuracy of diagnosing prostate cancer, data from studies investigating the feasibility of combining polyfocal (non-targeted) and targeted (targeted) biopsies are presented. Conclusion. The existing methods of non-targeted biopsy (polyfocal, saturation, template) and targeted (fusion biopsy) have their advantages and disadvantages, which currently do not allow making certain recommendations for their use, but a significant number of authors prefer MRI-as sisted, fusion -biopsy.


2021 ◽  
Vol 15 (9) ◽  
Author(s):  
James Ryan ◽  
Mark P. Broe ◽  
Diarmaid Moran ◽  
David Mulvin ◽  
Eric Heffernan ◽  
...  

Introduction: The use of multiparametric magnetic resonance imaging (MRI) with targeted biopsies of the prostate improves the diagnosis of clinically significant prostate cancer. Recent studies have shown that targeted prostate biopsies also more accurately predict final histopathology after radical prostatectomy (RP). There are three broad techniques for performing MRI-targeted prostate biopsy: cognitive MRI/ultrasound (US) fusion, software MRI/US fusion, and in-bore MRI-guided. Current practices recommend that a standard systematic 12-core prostate biopsy be performed, as well as targeted biopsies in patients with positive MRI findings. This study aimed to evaluate the accuracy of histological grading of cognitive MRI/US fusion prostate biopsy by comparing the histology from the targeted biopsy specimens (TB), standard systematic specimens (SB), and the combination of both (CB) specimens with the final histological grade from subsequent prostatectomy. Methods: A retrospective, single-center review of 115 patients who underwent standard systematic and cognitive MRI/US-targeted biopsy of the prostate before undergoing a RP between 2016 and 2019 was performed. MRI findings, biopsy, final histology International Society of Urological Pathology (ISUP) grades, and patient demographics were collected. Cochran’s Q test and McNemar test were used to compare the differences in upgrading, downgrading, and concordance between each biopsy group. Results: The concordance between SB, TB, and CB biopsy were 28.7%, 49.6%, and 50.4%, respectively. There was no significant difference in concordance between TB and CB. Patients were more likely to be downgraded on the final histology when comparing CB with TB alone (26.1% vs. 16.5%, p<0.05). In cases where an ISUP grade 1 cancer was diagnosed on TB (n=24), there was a 62.5% chance that the final histology would be upgraded. In the same sample, when combined with a SB, the risk of upgrading on final histology reduced to 37.5%. Conclusions: Although grading concordance between TB and CB were similar, the concomitant use of a SB significantly reduced the rate of upgrading in the final RP histopathology. CB may result in better decision-making regarding treatment options and also have implications for intraoperative planning.


2019 ◽  
Vol 20 (7) ◽  
pp. 1637 ◽  
Author(s):  
Daniël Osses ◽  
Monique Roobol ◽  
Ivo Schoots

This review discusses the most recent evidence for currently available risk stratification tools in the detection of clinically significant prostate cancer (csPCa), and evaluates diagnostic strategies that combine these tools. Novel blood biomarkers, such as the Prostate Health Index (PHI) and 4Kscore, show similar ability to predict csPCa. Prostate cancer antigen 3 (PCA3) is a urinary biomarker that has inferior prediction of csPCa compared to PHI, but may be combined with other markers like TMPRSS2-ERG to improve its performance. Original risk calculators (RCs) have the advantage of incorporating easy to retrieve clinical variables and being freely accessible as a web tool/mobile application. RCs perform similarly well as most novel biomarkers. New promising risk models including novel (genetic) markers are the SelectMDx and Stockholm-3 model (S3M). Prostate magnetic resonance imaging (MRI) has evolved as an appealing tool in the diagnostic arsenal with even stratifying abilities, including in the initial biopsy setting. Merging biomarkers, RCs and MRI results in higher performances than their use as standalone tests. In the current era of prostate MRI, the way forward seems to be multivariable risk assessment based on blood and clinical parameters, potentially extended with information from urine samples, as a triaging test for the selection of candidates for MRI and biopsy.


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