The Role of Tumor Oxygenation Tested by Magnetic Resonance Imaging (MRI) in Prostate Cancer Grading.
Geng Huaizhen,Tong Wen,Han Fangzheng,Zhu Kunming,Cao Yumei,Chen Xiude
Medical science monitor : international medical journal of experimental and clinical research
BACKGROUND Prostate cancer is a common malignant tumor in males. Prostate cancer grading is an important basis for evaluation of invasion. The purpose of this article was to use dynamic enhanced scan magnetic resonance imaging (MRI) to quantitatively investigate the relationship between tumor oxygenation value and prostate cancer pathological Gleason score. MATERIAL AND METHODS A total of 312 prostate cancer patients diagnosed by needle biopsy who received MRI dynamic enhanced scan were enrolled in this study. Multiparameter oxygen concentration image based on MRI was applied to test pO2 in tumors. Multiple spin resonance image relaxation time edit sequence and weak field diffusion model were used to estimate oxygen saturation level and pO2. hematoxylin and eosin staining and Gleason score were used to determine biological behavior and prognosis. RESULTS According to the Gleason score system, there were 28 cases with a score of 10, 112 cases with a score of 9, 56 cases with a score of 8, and 116 cases with a score lower than 7. The enrolled patients were divided into groups: 116 cases into the middle-to-well differentiation group (Gleason score ≤7) and 196 cases into the poorly differentiation group (Gleason score at 8 to 10). Prostate cancer tumor oxygenation value was positively correlated with Gleason score (r=0.349, P<0.05) or PSA (r=0.432, P<0.05). Tumor oxygenation value in Gleason ≤7 group was obviously different from that in the group with Gleason score between 9 and 10 (P<0.05). CONCLUSIONS Tumor oxygenation value in prostate cancer was positively correlated with Gleason score. Tumor oxygenation value might be useful in clinics to evaluate prostate cancer grading and prognosis.
Intravoxel Incoherent Motion Diffusion-Weighted Imaging Used to Detect Prostate Cancer and Stratify Tumor Grade: A Meta-Analysis.
He Ni,Li Zhipeng,Li Xie,Dai Wei,Peng Chuan,Wu Yaopan,Huang Haitao,Liang Jianye
Frontiers in oncology
Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) is a promising non-invasive imaging technique to detect and grade prostate cancer (PCa). However, the results regarding the diagnostic performance of IVIM-DWI in the characterization and classification of PCa have been inconsistent among published studies. This meta-analysis was performed to summarize the diagnostic performance of IVIM-DWI in the differential diagnosis of PCa from non-cancerous tissues and to stratify the tumor Gleason grades in PCa. Studies concerning the differential diagnosis of prostate lesions using IVIM-DWI were systemically searched in PubMed, Embase, and Web of Science without time limitation. Review Manager 5.3 was used to calculate the standardized mean difference (SMD) and 95% confidence intervals of the apparent diffusion coefficient (ADC), tissue diffusivity (D), pseudodiffusivity (D), and perfusion fraction (f). Stata 12.0 was used to pool the sensitivity, specificity, and area under the curve (AUC), as well as publication bias and heterogeneity. Fagan's nomogram was used to predict the post-test probabilities. Twenty studies with 854 patients confirmed with PCa were included. Most of the included studies showed a low to unclear risk of bias and low concerns regarding applicability. PCa showed a significantly lower ADC (SMD = -2.34; < 0.001) and D values (SMD = -1.86; < 0.001) and a higher D value (SMD = 0.29; = 0.01) than non-cancerous tissues, but no difference was noted with the f value (SMD = -0.16; = 0.50). Low-grade PCa showed higher ADC (SMD = 0.63; < 0.001) and D values (SMD = 0.80; < 0.001) than the high-grade lesions. ADC showed comparable diagnostic performance (sensitivity = 86%; specificity = 86%; AUC = 0.87) but higher post-test probabilities (60, 53, 36, and 36% for ADC, D, D, and f values, respectively) compared with the D (sensitivity = 82%; specificity = 82%; AUC = 0.85), D (sensitivity = 70%; specificity = 70%; AUC = 0.75), and f values (sensitivity = 73%; specificity = 68%; AUC = 0.76). IVIM parameters are adequate to differentiate PCa from non-cancerous tissues with good diagnostic performance but are not superior to the ADC value. Diffusion coefficients can further stratify the tumor Gleason grades in PCa.
MR imaging and MR spectroscopic imaging in the pre-treatment evaluation of prostate cancer.
The British journal of radiology
Magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRSI) are emerging as the most sensitive tools for the non-invasive, anatomic and metabolic evaluation of prostate cancer. This article reviews the current applications of MRI and 1H MRSI in clinical practice and discusses the promise of these modalities for improving prostate cancer management. MRI demonstrates zonal anatomy with excellent contrast resolution and can reveal tumours in areas not routinely sampled on biopsy and not palpable on digital rectal examination. In addition, MR images allow assessment of local extent (including extracapsular extension and seminal vesicle invasion) and thus can assist in local staging while providing surgeons and radiation therapists with a visual road-map for treatment planning. The addition of 1H MRSI to MRI can improve prostate cancer detection and assessment of tumour volume; it also contributes indirectly to improved local staging. In addition, 1H MRSI metabolic and volumetric data correlate with pathological Gleason grade and thus may offer a non-invasive means to better predict prostate cancer aggressiveness. Combined MRI/1H MRSI is currently of greatest value for high-risk patients. With greater understanding of the relationship between spectroscopic data and tumour biology, it may become possible to use MRI/1H MRSI to achieve more precise stratification of patients in clinical trials, to monitor the progress of patients who select watchful waiting or minimally aggressive cancer therapies, and to guide and assess emerging local prostate cancer therapies.
Non-invasive estimation of prostate cancer aggressiveness using diffusion-weighted MRI and 3D proton MR spectroscopy at 3.0 T.
Thörmer Gregor,Otto Josephin,Horn Lars-Christian,Garnov Nikita,Do Minh,Franz Toni,Stolzenburg Jens-Uwe,Moche Michael,Kahn Thomas,Busse Harald
Acta radiologica (Stockholm, Sweden : 1987)
BACKGROUND:Clinical management of prostate cancer increasingly aims to distinguish aggressive types that require immediate and radical treatment from indolent tumors that are candidates for watchful waiting. This requires reliable and reproducible parameters to effectively control potential cancer progression. Magnetic resonance imaging (MRI) may provide a non-invasive means for this purpose. PURPOSE:To assess the value of diffusion-weighted imaging and proton MR spectroscopy for the prediction of prostate cancer (PCa) aggressiveness. MATERIAL AND METHODS:In 39 of 64 consecutive patients who underwent endorectal 3-T MRI prior to radical prostatectomy, prostate specimens were analyzed as whole-mount step sections. Apparent diffusion coefficient (ADC), normalized ADC (nADC: tumor/healthy tissue), choline/citrate (CC), and (choline + creatine)/citrate (CCC) ratios were correlated with Gleason scores (GS) from histopathological results. The power to discriminate low (GS ≤ 6) from higher-risk (GS ≥ 7) tumors was assessed with receiver operating characteristics (area under the curve [AUC]). Resulting threshold values were used by a blinded reader to distinguish between aggressive and indolent tumors. RESULTS:Ninety lesions (1 × GS = 5, 41 × GS = 6, 36 × GS = 7, 12 × GS = 8) were considered. nADC (AUC = 0.90) showed a higher discriminatory power than ADC (AUC = 0.79). AUC for CC and CCC were 0.73 and 0.82, respectively. Using either nADC < 0.46 or CCC > 1.3, as well as both criteria for aggressive PCa, the reader correctly identified aggressive and indolent tumors in 31 (79%), 28 (72%), and 33 of 39 patients (85%), respectively. Predictions of tumor aggressiveness from TRUS-guided biopsies were correct in 27 of 36 patients (75%). CONCLUSION:The combination of a highly sensitive normalized ADC with a highly specific CCC was found to be well suited to prospectively estimate PCa aggressiveness with a similar diagnostic accuracy as biopsy results.
Elevated Tumor Lactate and Efflux in High-grade Prostate Cancer demonstrated by Hyperpolarized C Magnetic Resonance Spectroscopy of Prostate Tissue Slice Cultures.
Sriram Renuka,Van Criekinge Mark,DeLos Santos Justin,Ahamed Fayyaz,Qin Hecong,Nolley Rosalie,Santos Romelyn DeLos,Tabatabai Z Laura,Bok Robert A,Keshari Kayvan R,Vigneron Daniel B,Peehl Donna M,Kurhanewicz John
Non-invasive assessment of the biological aggressiveness of prostate cancer (PCa) is needed for men with localized disease. Hyperpolarized (HP) C magnetic resonance (MR) spectroscopy is a powerful approach to image metabolism, specifically the conversion of HP [1-C]pyruvate to [1-C]lactate, catalyzed by lactate dehydrogenase (LDH). Significant increase in tumor lactate was measured in high-grade PCa relative to benign and low-grade cancer, suggesting that HP C MR could distinguish low-risk (Gleason score ≤3 + 4) from high-risk (Gleason score ≥4 + 3) PCa. To test this and the ability of HP C MR to detect these metabolic changes, we cultured prostate tissues in an MR-compatible bioreactor under continuous perfusion. P spectra demonstrated good viability and dynamic HP C-pyruvate MR demonstrated that high-grade PCa had significantly increased lactate efflux compared to low-grade PCa and benign prostate tissue. These metabolic differences are attributed to significantly increased expression and LDH activity, as well as significantly increased monocarboxylate transporter 4 (MCT4) expression in high- versus low- grade PCa. Moreover, lactate efflux, LDH activity, and MCT4 expression were not different between low-grade PCa and benign prostate tissues, indicating that these metabolic alterations are specific for high-grade disease. These distinctive metabolic alterations can be used to differentiate high-grade PCa from low-grade PCa and benign prostate tissues using clinically translatable HP [1-C]pyruvate MR.