Comparison between breast MRI and contrast-enhanced spectral mammography.

BACKGROUND: The main goal of this study was to compare contrast-enhanced spectral mammography (CESM) and breast magnetic resonance imaging (MRI) with histopathological results and to compare the sensitivity, accuracy, and positive and negative predictive values for both imaging modalities. MATERIAL/METHODS: After ethics approval, CESM and MRI examinations were performed in 102 patients who had suspicious lesions described in conventional mammography. All visible lesions were evaluated independently by 2 experienced radiologists using BI-RADS classifications (scale 1-5). Dimensions of lesions measured with each modality were compared to postoperative histopathology results. RESULTS: There were 102 patients entered into CESM/MRI studies and 118 lesions were identified by the combination of CESM and breast MRI. Histopathology confirmed that 81 of 118 lesions were malignant and 37 were benign. Of the 81 malignant lesions, 72 were invasive cancers and 9 were in situ cancers. Sensitivity was 100% with CESM and 93% with breast MRI. Accuracy was 79% with CESM and 73% with breast MRI. ROC curve areas based on BI-RADS were 0.83 for CESM and 0.84 for breast MRI. Lesion size estimates on CESM and breast MRI were similar, both slightly larger than those from histopathology. CONCLUSIONS: Our results indicate that CESM has the potential to be a valuable diagnostic method that enables accurate detection of malignant breast lesions, has high negative predictive value, and a false-positive rate similar to that of breast MRI.

Correlation between CT perfusion and clinico-pathological features in prostate cancer: a prospective study.

BACKGROUND: The aim of the study was to assess the correlation between computed tomography perfusion (PCT) parameters and PSA levels, Gleason score, and pTNM stage in patients with prostate cancer (PCa). MATERIAL/METHODS: One hundred twenty-five patients with localized PCa were prospectively enrolled in the study. All patients were diagnosed due to suspicious prostate findings and elevated PSA serum levels and underwent PCT followed by core biopsy and radical prostatectomy. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface (PS) area product were computed in the suspected PCa area and normal prostatic tissue. Core biopsy followed by prostatectomy was performed 2-4 weeks after PCT. Correlation between PCT findings and PSA levels, Gleason score, and pTNM stage were analyzed. RESULTS: The mean age of patients was 64 years. All patients had elevated PSA levels (mean value 6.2 ng/ml). Nineteen patients (15.9%) were at low risk of recurrence, 91 (76.5%) were at moderate risk, and 9 (7.6%) were at high risk according to National Comprehensive Cancer Network criteria. PCa was visible on PCT as focal peripheral CT enhancement in 119 out of 125 patients (sensitivity 95.2%). Significant correlations between BV, BF, and PS values and PSA level were found (p<0.05), as well as a trend for difference between BV, BF, and PS in poorly and moderately differentiated tumors (according to Gleason score) in comparison with highly differentiated PCa (p<0.08). The analysis also revealed a correlation between mean perfusion values and BV, MTT, PS, and pTNM cancer stage (p<0.04). CONCLUSIONS: Our study suggests that in low- and intermediate- risk patients, PCT parameters correlate with PSA values, Gleason score, and pTNM stage and can be useful for initial tumor staging.

The Utility of Diffusion Weighted Imaging (DWI) Using Apparent Diffusion Coefficient (ADC) Values in Discriminating Between Prostate Cancer and Normal Tissue.

BACKGROUND: The aim of this study was to investigate the utility of diffusion weighted imaging (DWI) using Apparent Diffusion Coefficient (ADC) values in discriminating between patients with tumors and normal prostate tissue before the initial systematic core biopsy. The relationship between histological grade of prostate cancer and ADC values in the peripheral zone was also investigated. MATERIAL/METHODS: Our study included 62 patients who underwent magnetic resonance imaging (MRI) of the pelvis. The examinations were performed in T1-, T2-weighted, DWI and T1 after dynamic contrast administration sequences. In all patients there were abnormal foci within the peripheral zone determined in DWI/ADC. ADC values were compared with the Gleason score (GS) after core needle biopsy (CNB) in patients with low, medium and high stage tumors. RESULTS: Within the examined group of patients, ADC was statistically higher for normal tissue than for cancerous tissue (p=0.00). Mean ADC values for patients with low, intermediate and high GS were 0.85±0.03, 0.72±0.03, and 0.61±0.04, respectively. CONCLUSIONS: DWI/ADC is useful in differentiating high-risk patients from those at low and intermediate risk, since there is a significant correlation between ADC values determined in patients included in three different groups according to their Gleason score. This information may be helpful in the assessment of prostate cancer aggressiveness.

Contrast-enhanced spectral mammography: comparison with conventional mammography and histopathology in 152 women.

OBJECTIVE: The goal of the study was to compare conventional mammography (MG) and contrast-enhanced spectral mammography (CESM) in preoperative women. MATERIALS AND METHODS: The study was approved by the local Ethics Committee and all participants provided informed consent. The study included 152 consecutive patients with 173 breast lesions diagnosed on MG or CESM. All MG examinations and consults were conducted in one oncology centre. Non-ionic contrast agent, at a total dose of 1.5 mL/kg body weight, was injected intravenous. Subsequently, CESM exams were performed with a mammography device, allowing dual-energy acquisitions. The entire procedure was done within the oncology centre. Images from low and high energy exposures were processed together and the combination provided an "iodine" image which outlined contrast up-take in the breast. RESULTS: MG detected 157 lesions in 150 patients, including 92 infiltrating cancers, 12 non-infiltrating cancers, and 53 benign lesions. CESM detected 149 lesions in 128 patients, including 101 infiltrating cancers, 13 non-infiltrating cancers, and 35 benign lesions. CESM sensitivity was 100% (vs. 91% for MG), specificity was 41% (vs. 15% for MG), area under the receiver operating characteristic curve was 0.86 (vs. 0.67 for MG), and accuracy was 80% (vs. 65% for MG) for the diagnosis of breast cancer. Both MG and CESM overestimated lesion sizes compared to histopathology (p < 0.001). CONCLUSION: CESM may provide higher sensitivity for breast cancer detection and greater diagnostic accuracy than conventional mammography.

The effect of the renin-angiotensin-aldosterone system inhibition on myocardial function in early and late phases of dilated cardiomyopathy in Tgaq*44 mice.

BACKGROUND: The renin-angiotensin-aldosterone system (RAAS) determines progression of heart failure (HF) in humans, and RAAS inhibition is a major therapeutic strategy in HF. AIM: To assess the effect of angiotensin-converting enzyme inhibitor (ACE-I) and aldosterone receptor antagonist (ARA) therapy on the development of HF at its early and late stage in a murine model of dilated cardiomyopathy (Tgaq*44 mice). METHODS: Tgaq*44 mice at the early or advanced stage of HF received combined therapy including ACE-I (perindopril 2 mg/kg) and ARA (canrenone 20 mg/kg). Cardiac function was assessed by magnetic resonance imaging before and after 2 months of treatment. RESULTS: Combined therapy with perindopril and canrenone resulted in preserved systolic function at the early stage and reduced chamber dilatation at the advanced stage of HF in Tgaq*44 mice. CONCLUSIONS: Activation of the RAAS is involved in progression of HF in Tgaq*44 mice with dilated cardiomyopathy. Therapeutic efficacy of ACE-I and ARA to inhibit systolic dysfunction and cardiac chamber dilation depends on the stage of HF development.

Nephrectomy or nephron-sparing surgery - how to decide?

AIM OF THE STUDY: Radical nephrectomy in the treatment of renal cell carcinoma (RCC) remains the gold standard, but nephron-sparing surgery (NSS) is still increasing in importance. The main goal of this study was to compare the diagnostic accuracy of ultrasound and multi-detector computed tomography in RCC staging and its influence on deciding about further patient treatment. MATERIAL AND METHODS: 87 patients (age range 27-90 years; median 61.5) underwent ultrasound (US) scan and contrast-enhanced computed tomography (CE-CT) of the abdomen and pelvis. 28 patients were qualified for NSS. The remaining group of patients underwent nephrectomy. RESULTS: NSS was performed more frequently among patients with lesions in the lower pole of the kidney and there was no infiltration to the calyx and renal pelvis. Radical nephrectomy (RN) was pursued in cases with lesions in the central or upper pole. Lesion diameter in patients qualified for NSS was smaller than in patients qualified for radical nephrectomy. CONCLUSIONS: Determining the relationship between tumour and adjacent structures is not a simple matter. According to our study, 50% of CT results differ from histopathology assessment. Tumour diameter determined in CT examination is larger than in ultrasound and histopathological measurements while US scanning tends to underestimate tumour size in relation to histopathological assessment.

Application of magnetic resonance imaging in vivo for the assessment of the progression of systolic and diastolic dysfunction in a mouse model of dilated cardiomyopathy.

BACKGROUND: The impairment of cardiac diastolic function is essential for the development and progression of heart failure, regardless of the systolic performance of the heart. Novel methods of diagnosis of diastolic dysfunction in experimental animals are needed in order to validate the effectiveness of novel heart failure treatment. AIM: The in vivo characterisation of diastolic and systolic function of the heart during heart failure progression in Tgalphaq*44 mice using magnetic resonance imaging (MRI) and original image analysis. METHODS: Cardiac function in vivo in both Tgalphaq*44 and FVB mice was analysed using MRI at 4.7 T. Magnetic resonance imaging was performed using an ECG triggered fast gradient echo (cine-like flow compensated FLASH) sequence. For the assessment of left ventricle (LV) dynamics at least 20 images per cardiac cycle were acquired in the midventricular short-axis projection at the level of papillary muscles. End-systolic (ESA) and end-diastolic (EDA) areas were estimated from the minimum and maximum values found in the area-time plot. Fractional area change (FAC) defined as (EDA-ESA)/EDA, ejection (ER) and filling (FR) rates defined as slope of the beginning part of the systolic and diastolic limbs were calculated. In addition, heart failure progression in Tgalphaq*44 mice was assessed by morphometric parameters (ventricular weight to body weight index and wet to dry lung weight index), level of BNP mRNA expression as well as survival. RESULTS: Systolic function assessed by FAC% and ER was stable but slightly impaired up to 10 months of age in Tgalphaq*44 mice as compared to the FVB mice. After 12 months of age of the Tgalphaq*44 mice there was a progressive deterioration of systolic function (ER at 10, 12, 14 months of age were 0.0188 +/- 0.00434, 0.0140 +/- 0.00474, 0.0115 +/- 0.00469 1/ms, respectively). Diastolic function of the Tgalphaq*44 hearts was preserved or even slightly augmented between 4 and 10 months of age, then at the age of 12 months and later profoundly impaired (FR at 10, 12, 14 months of age were 0.0280 +/- 0.01031, 0.0196 +/- 0.01050, 0.0158 +/- 0.00833 1/ms, respectively). CONCLUSIONS: The MRI allows reliable in vivo assessment of the systolic and diastolic function in Tgalphaq*44 mice. In Tgalphaq*44 mice after few months of stable and compensated phase of the heart failure decompensation develops that involves impairment of both systolic and diastolic and leads to the fully symptomatic dilated cardiomyopathy. The precise molecular mechanisms of the systolic and diastolic dysfunction and their relative contribution to the heart failure progression in Tgalphaq*44 mice remain to be established.

Detection of mitochondrial dysfunction by EPR technique in mouse model of dilated cardiomyopathy.

Tgalphaq44 mice with targeted overexpression of activated Galphaq protein in cardiomyocytes mimic many of the phenotypic characteristics of dilated cardiomyopathy in humans. However, it is not known whether the phenotype of Tgalphaq44 mice would also involve dysfunction of cardiac mitochondria. The aim of the present work was to examine changes in EPR signals of semiquinones and iron in Fe-S clusters, as compared to classical biochemical indices of mitochondrial function in hearts from Tgalphaq44 mice in relation to the progression of heart failure. Tgalphaq44 mice at the age of 14 months displayed pulmonary congestion, increased heart/body ratio and impairment of cardiac function as measured in vivo by MRI. However, in hearts from Tgalphaq44 mice already at the age of 10 months EPR signals of semiquinones, as well as cyt c oxidase activity were decreased, suggesting alterations in mitochondrial electron flow. Furthermore, in 14-months old Tgalphaq44 mice loss of iron in Fe-S clusters, impaired citrate synthase activity, and altered mitochondrial ultrastructure were observed, supporting mitochondrial dysfunction in Tgalphaq44 mice. In conclusion, the assessment of semiquinones content and Fe(III) analysis by EPR represents a rational approach to detect dysfunction of cardiac mitochondria. Decreased contents of semiquinones detected by EPR and a parallel decrease in cyt c oxidase activity occurs before hemodynamic decompensation of heart failure in Tgalphaq44 mice suggesting that alterations in function of cardiac mitochondria contribute to the development of the overt heart failure in this model.

NO and PGI(2) in coronary endothelial dysfunction in transgenic mice with dilated cardiomyopathy.

OBJECTIVE: The aim of the present work was to analyze coronary endothelial function in the transgenic mouse model of dilated cardiomyopathy (Tgalphaq*44 mice). METHODS: Coronary vasodilatation, both NO-dependent (induced by bradykinin) and PGI(2)-dependent (induced by acetylcholine), was assessed in the isolated hearts of Tgalphaq*44 and FVB mice. Cardiac function was analyzed in vivo (MRI). RESULTS: In Tgalphaq*44 mice at the age of 2-4 months cardiac function was preserved and there were no alterations in endothelial function. By contrast, in Tgalphaq*44 mice at the age of 14-16 months cardiac function was significantly impaired and NO, but not PGI(2)-dependent coronary function was altered. Interestingly, the basal level of PGI(2) in coronary circulation increased fourfold as compared to FVB mice. Cardiac O(2) (-) production increased 1.5-fold and 3-fold in Tgalphaq*44 vs. FVB mice at the age of 2-6 and 14-16 months, respectively, and was inhibited by apocynin. Interestingly, inhibition of NADPH oxidase or NOS-3 normalized augmented PGI(2) production in Tgalphaq*44 mice. There was also an increased expression of gp91phox in Tgalphaq*44 vs. FVB hearts, without evident alterations in the expression of COX-1, COX-2, NOS-3 and PGI(2)-synthase. CONCLUSIONS: In the mouse model of dilated cardiomyopathy, endothelial dysfunction in coronary circulation is present in the late but not the early stage of heart failure pathology and is characterized by a decrease in NO bioavailability and a compensatory increase in PGI(2). Both the decrease in NO activity and the increase in PGI(2) activity may result from excessive O(2) (-) production by cardiac NADPH oxidase in Tgalphaq*44 hearts.