Digital breast tomosynthesis and contrast-enhanced dual-energy digital mammography alone and in combination compared to 2D digital synthetized mammography and MR imaging in breast cancer detection and classification.

To compare diagnostic performance of contrast-enhanced dual-energy digital mammography (CEDM) and digital breast tomosynthesis (DBT) alone and in combination compared to 2D digital mammography (MX) and dynamic contrast-enhanced MRI (DCE-MRI) in women with breast lesions. We enrolled 100 consecutive patients with breast lesions (BIRADS 3-5 at imaging or clinically suspicious). CEDM, DBT, and DCE-MRI 2D were acquired. Synthetized MX was obtained by DBT. A total of 134 lesions were investigated on 111 breasts of 100 enrolled patients: 53 were histopathologically proven as benign and 81 as malignant. Nonparametric statistics and receiver operating characteristic (ROC) curve were performed. Two-dimensional synthetized MX showed an area under ROC curve (AUC) of 0.764 (sensitivity 65%, specificity 80%), while AUC was of 0.845 (sensitivity 80%, specificity 82%) for DBT, of 0.879 (sensitivity 82%, specificity 80%) for CEDM, and of 0.892 (sensitivity 91%, specificity 84%) for CE-MRI. DCE-MRI determined an AUC of 0.934 (sensitivity 96%, specificity 88%). Combined CEDM with DBT findings, we obtained an AUC of 0.890 (sensitivity 89%, specificity 74%). A difference statistically significant was observed only between DCE-MRI and CEDM (P = .03). DBT, CEDM, CEDM combined to tomosynthesis, and DCE-MRI had a high ability to identify multifocal and bilateral lesions with a detection rate of 77%, 85%, 91%, and 95% respectively, while 2D synthetized MX had a detection rate for multifocal lesions of 56%. DBT and CEDM have superior diagnostic accuracy of 2D synthetized MX to identify and classify breast lesions, and CEDM combined with DBT has better diagnostic performance compared with DBT alone. The best results in terms of diagnostic performance were obtained by DCE-MRI. Dynamic information obtained by time-intensity curve including entire phase of contrast agent uptake allows a better detection and classification of breast lesions.

Abbreviated breast dynamic contrast-enhanced MR imaging for lesion detection and characterization: the experience of an Italian oncologic center.

BACKGROUND: To evaluate the performance of an abbreviated dynamic contrast-enhanced MR imaging (MRI) protocol for breast cancer detection; a comparison with the complete diagnostic protocol has been conducted. METHODS: A retrospective analysis on 508 patients was performed. Abbreviated protocol (AP) included one pre-contrast and the first post-contrast T1-weighted series. Complete protocol (CP) consisted of four post-contrast and one pre-contrast T1-weighted series. Diagnostic performance was assessed for AP and CP. Performance comparison was made using McNemar's test for sensitivity and specificity and Moskowitz and Pepe's method as regards negative predictive value (NPV) and positive predictive value (PPV). AP has been realized in two different ways (AP1 and AP2) and they were compared by means of Cohen's κ. RESULTS: Both CP and AP revealed 206 of 207 cancers. There were no statistically significant differences between AP and CP diagnostic performance (P > 0.05). NPVs of CP and both versions of AP (99.57 vs. 99.56%, P = 0.39), as well as the specificity (77.08 vs. 75.42%, P = 0.18), were substantially equivalent. Relative predictive value method did not reveal the presence of a statistically significant difference between the PPV of CP and both versions of AP (74.91 vs. 73.57%, P = 0.099). Analysis for single lesion confirmed that both CP and AP had equivalent results: CP and AP revealed 280 of 281 malignancies. NPVs of CP and both AP versions, as well as the specificity (P > 0.05), were substantially equivalent. Relative predictive value method did not reveal the presence of a significant difference between the PPV of CP and both AP versions (70.89 vs. 70.18%, P = 0.25; 70.89 vs. 70.00%, P = 0.13). CONCLUSIONS: Abbreviated approach to breast MRI examination reduces the image acquisition and the reading time associated with MR substantially without influencing the diagnostic accuracy (high sensitivity and NPV >99.5%). AP could translate into cost-savings and could enable a higher number of examinations within the same MR session.

Magnetic Resonance Imaging Evaluation in Neoadjuvant Therapy of Locally Advanced Rectal Cancer: A Systematic Review.

BACKGROUND: The aim of the study was to present an update concerning several imaging modalities in diagnosis, staging and pre-surgery treatment response assessment in locally advanced rectal cancer (LARC). Modalities include: traditional morphological magnetic resonance imaging (MRI), functional MRI such as dynamic contrast enhanced MRI (DCE-MRI) and diffusion weighted imaging (DWI). A systematic review about the diagnostic accuracy in neoadjuvant therapy response assessment of MRI, DCE-MRI, DWI and Positron Emission Tomography/Computed Tomography (PET/CT) has been also reported. METHODS: Several electronic databases were searched including PubMed, Scopus, Web of Science, and Google Scholar. All the studies included in this review reported findings about therapy response assessment in LARC by means of MRI, DCE-MRI, DWI and PET/CT with details about diagnostic accuracy, true and false negatives, true and false positives. Forest plot and receiver operating characteristic (ROC) curves analysis were performed. Risk of bias and the applicability at study level were calculated. RESULTS: Twenty-five papers were identified. ROC curves analysis demonstrated that multimodal imaging integrating morphological and functional MRI features had the best accuracy both in term of sensitivity and specificity to evaluate preoperative therapy response in LARC. DCE-MRI following to PET/CT showed high diagnostic accuracy and their results are also more reliable than conventional MRI and DWI alone. CONCLUSIONS: Morphological MRI is the modality of choice for rectal cancer staging permitting a correct assessment of the disease extent, of the lymph node involvement, of the mesorectal fascia and of the sphincter complex for surgical planning. Multimodal imaging and functional DCE-MRI may also help in the assessment of treatment response allowing to guide the surgeon versus conservative strategies and/or tailored approach such as "wait and see" policy.

Pattern Recognition Approaches for Breast Cancer DCE-MRI Classification: A Systematic Review.

We performed a systematic review of several pattern analysis approaches for classifying breast lesions using dynamic, morphological, and textural features in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Several machine learning approaches, namely artificial neural networks (ANN), support vector machines (SVM), linear discriminant analysis (LDA), tree-based classifiers (TC), and Bayesian classifiers (BC), and features used for classification are described. The findings of a systematic review of 26 studies are presented. The sensitivity and specificity are respectively 91 and 83 % for ANN, 85 and 82 % for SVM, 96 and 85 % for LDA, 92 and 87 % for TC, and 82 and 85 % for BC. The sensitivity and specificity are respectively 82 and 74 % for dynamic features, 93 and 60 % for morphological features, 88 and 81 % for textural features, 95 and 86 % for a combination of dynamic and morphological features, and 88 and 84 % for a combination of dynamic, morphological, and other features. LDA and TC have the best performance. A combination of dynamic and morphological features gives the best performance.

Surgical impact of preoperative breast MRI in women below 40 years of age.

Our aim was to evaluate the surgical impact of preoperative MRI in young patients. We reviewed a single-institution database of 283 consecutive patients below 40 years of age and who were treated for breast cancer. Thirty-seven (13 %) patients who received neoadjuvant chemotherapy were excluded. The remaining 246 patients included 124 (50 %) who preoperatively underwent conventional imaging (CI), i.e., mammography/ultrasonography (CI-group), and 122 (50 %) who underwent CI and dynamic MRI (CI + MRI-group). Pathology of surgical specimens served as a reference standard. Mann-Whitney, χ (2), and McNemar statistics were used. There were no significant differences between groups in terms of age, tumor pathologic subtype, stage, receptor, or nodal status. The mastectomy rate was 111/246 (45 %) overall but was significantly different between groups (46/124, 37 %, for the CI group and 65/122, 53 %, for the CI + MRI group; p = 0.011). Of 122 CI + MRI patients, 46 (38 %) would have undergone mastectomy due to CI alone, while MRI determined 19 additional mastectomies, increasing the mastectomy rate from 38 % to 53 % (p < 0.001). The number of patients with multifocal, multicentric, synchronous, or bilateral cancers was significantly different between groups (10/124, 8 %, for the CI group and 33/122, 27 %, for the CI + MRI group; p < 0.001). In the CI + MRI group, multifocal, multicentric, or synchronous bilateral cancers were detected with mammography in 5/33 (15 %) patients, with ultrasonography in 15/33 (45 %) patients, and with MRI in 32/33 (97 %) patients (p < 0.005). Two mastectomies were due to false positives at both conventional tests in the CI group (2/124, 1.6 %) and two mastectomies were due to MRI false positives in the CI + MRI group (2/122, 1.6 %). In conclusion, breast cancer in young patients was treated with mastectomy in 37-38 % of cases on the basis of CI only and in these patients MRI was more sensitive than CI for multifocal, multicentric, or synchronous bilateral cancers, resulting in an additional mastectomy rate of 15 %. A low probability of inappropriate imaging-based decision-making for mastectomy exists for both CI alone and for CI + MRI, making presurgical needle biopsy mandatory for findings that suggest a need for mastectomy.

The current role and future prospectives of functional parameters by diffusion weighted imaging in the assessment of histologic grade of HCC.

Hepatocellular carcinoma (HCC) is one of the most common human solid malignancies worldwide. Although the MRI is the technique that is best adapted to characterize HCC, there is not an agreement regarding the study protocol and even what the role of Diffusion-weighted imaging (DWI). The possibility that imaging study can correlate to histologic grade to selecting the therapeutic strategy would be valuable in helping to direct the proper management of HCC. Apparent Diffusion Coefficient (ADC) and IVIM-derived perfusion fraction (fp) and tissue diffusivity (Dt) values of HCC showed significantly better diagnostic performance in differentiating high-grade HCC from low-grade HCC, and significant correlation was observed between ADC, fp, Dt and histological grade.

Assessing response to neo-adjuvant therapy in locally advanced rectal cancer using Intra-voxel Incoherent Motion modelling by DWI data and Standardized Index of Shape from DCE-MRI.

BACKGROUND: Our aim was to investigate preoperative chemoradiation therapy (pCRT) response in locally advanced rectal cancer (LARC) comparing standardized index of shape (SIS) obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with intravoxel-incoherent-motion-modelling-derived parameters by diffusion-weighted imaging (DWI). MATERIALS AND METHODS: Eighty-eight patients with LARC were subjected to MRI before and after pCRT. Apparent diffusion coefficient (ADC), tissue diffusion (Dt), pseudodiffusion (Dp) and perfusion fraction (f) were calculated and percentage changes ∆ADC, ∆Dt, ∆Dp, ∆f were computed. SIS was derived comparing DCE-MRI pre- and post-pCRT. Nonparametric tests and receiver operating characteristic (ROC) curves were performed. RESULTS: A total of 52 patients were classified as responders (tumour regression grade; TRG ⩽ 2) and 36 as not-responders (TRG > 3). Mann-Whitney U test showed statistically significant differences in SIS, ∆ADC and ∆Dt between responders and not-responders and between complete responders (19 patients with TRG = 1) versus incomplete responders. The best parameters to discriminate responders by nonresponders were SIS and ∆ADC, with an accuracy of 91% and 82% (cutoffs of -5.2% and 18.7%, respectively); the best parameters to detect pathological complete responders were SIS, ∆f and ∆Dp with an accuracy of 78% (cutoffs of 38.5%, 60.0% and 83.0%, respectively). No increase of performance was observed by combining linearly each possible couple of parameters or combining all parameters. CONCLUSION: SIS allows assessment of preoperative treatment response with high accuracy guiding the surgeon versus more or less conservative treatment. DWI-derived parameters reached less accuracy compared with SIS and combining linearly DCE- and DWI-derived parameters; no increase of accuracy was obtained.

Optical imaging of the breast: evaluation of deoxyhemoglobin concentration alteration in 166 patients with suspicious breast lesions.

BACKGROUND: We investigated the performance of optical imaging evaluating deoxyhemoglobin concentration alteration (DeHCA) in breast tissues. METHODS: We enrolled all consecutive patients from January 2015 to October 2016 with clinically suspicious and/or BI-RADS grade 3-5 lesions at mammography or ultrasound (US). Patients underwent optical imaging (ComfortScan) to evaluate for DeHCA. The reference standard was pathology from a surgical specimen for malignant lesions, pathology from a surgical specimen or core needle biopsy for benign lesions, and negative follow-up for contralateral negative breasts. Non-parametric statistics, receiver operating characteristic, and linear discrimination analyses were performed. RESULTS: Of 334 enrolled patients, 168 (50%) were excluded for technical problems and 166 (50%) (median age 52 years) were analyzed totaling 331 breasts and 176 lesions. Of these, 75 were benign (median size 19 mm) and 101 malignant (median size 20 mm). The median DeHCA score in malignant lesions (0.95, interquartile range [IQR] 1.00-0.87) was higher (p < 0.001) than in benign lesions (0.80, IQR 0.95-0.70). Using the optimal cutoff (0.85), DeHCA score was less accurate than mammography, US, and their combination, with 78% sensitivity, 52% specificity, 40% positive predictive value (PPV), and 85% negative predictive value (NPV); using a 0.8 cutoff, sensitivity reached 93% and NPV 91%, but specificity fell to 32% and PPV to 37%. The accuracy of DeHCA score linearly combined with mammography or US was higher than that of DeHCA score alone (p < 0.001) and not significantly higher than that of mammography or US alone. CONCLUSIONS: DeHCA score was significantly higher in malignant than in benign lesions, but its accuracy was significantly lower than that of mammography or US. Future refinements are needed.

Uncommon neoplasms of the biliary tract: radiological findings.

OBJECTIVE: To report our cancer centre experience in the biliary tumours incidence other than cholangiocellular-carcinoma, emphasizing the radiological features. METHODS: 197 patients with biliary disease undergoing Gd-EOB-DTPA-enhanced MRI were reviewed. Four radiologists evaluated retrospectively size, structure, anatomical site and signal intensity of lesions on MRI. Enhancement-pattern during the arterial-, portal- and late-phase on ultrasound, CT and MR study was assessed as well as the enhancement pattern during the hepatobiliary-phase on MRI. RESULTS: 23 patients were selected. The lesion was intraductal in 5 cases, periductal in 14 and intrahepatic in 4. 16 lesions were solid, 5 uniloculated cystic and 2 complex cystic. In five patients the lesion was simple cyst, with a signal intensity in T1 weighted (T1W) and T2 weighted (T2W) similar to the gallbladder. In two patients with complex cystic lesion, the solid component was heterogeneously hypointense in T1 W, hyperintense in T2 W with a restricted diffusion. The solid component showed heterogeneous contrast-enhancement on CT, MR and ultrasound. The tumour was intrahepatic in two patients, with signal hypointense in T1 W and hyperintense in T2 W. Diffusion was restricted. The lesions showed heterogeneous contrast-enhancement. The periductal lesions were hypointense in T1 W, hyperintense in T2 W with restricted diffusion. The lesion showed progressive contrast-enhancement. Peribiliary melanoma was hyperintense in T1 W, hyperintense in T2 W with restricted diffusion and progressively contrast-enhanced. CONCLUSION: Biliary tumours can have a wide spectrum of radiologic appearances and consequently represent a diagnostic challenge for the radiologist. Advances in knowledge: MRI is the technique of choice in diagnosing biliary tumours, including rare (non-CCC) tumours.

Added Value of Breast MRI for Preoperative Diagnosis of Ductal Carcinoma In Situ: Diagnostic Performance on 362 Patients.

INTRODUCTION: The purpose of this study was to evaluate the added value of breast magnetic resonance imaging (MRI) in preoperative diagnosis of ductal carcinoma in situ (DCIS). We reviewed our institution database of 3499 consecutive patients treated for breast cancer. PATIENTS AND METHODS: A total of 362 patients with histologically proven DCIS were selected from the institutional database. Of these, 245 (67.7%) preoperatively underwent conventional imaging (CI) (mammography/ultrasonography) (CI group), and 117 (32.3%) underwent CI and dynamic MRI (CI + MRI group). The pathology of surgical specimens served as a reference standard. The Mann-Whitney U, χ2 test, and Spearman correlation coefficient were performed. RESULTS: The CI + MRI group showed a sensitivity of 98.5% with an increase of 10.1% compared with the CI group to detect pure DCIS. Dynamic MRI identified 19.7% (n = 13) additional pure DCIS compared with CI. In the CI + MRI group, a single (1.5%) false negative was reported, whereas in the CI group, 11 (11.6%) false negatives were reported. Moreover, the CI + MRI group showed a sensitivity of 98.0% to detect DCIS + small invasive component. In this group, dynamic MRI identified 21.6% (n = 11) additional DCIS and a single (2.0%) false negative compared with the CI group, whereas in the CI group, 7 (4.7%) false negatives were reported. MRI and histopathologically measured lesion sizes, Breast Imaging Reporting and Data System MRI assessment categories, and enhancement signal intensity curve types showed a significant correlation. The MRI detection rate of DCIS increased significantly with increasing nuclear grade. CONCLUSIONS: Preoperative breast MRI showed a better accuracy then CI in preoperative diagnosis for both pure DCIS and DCIS + small invasive component with a precise assessment of lesion size. This can provide a more appropriate management of DCIS patients.

Breast contrast-enhanced MR imaging: semiautomatic detection of vascular map.

BACKGROUND: The diagnostic value of breast vascular maps using contrast-enhanced MR imaging has recently been explored. We propose a semiautomatic method to obtain breast vascular maps and to measure the number of blood vessels in the breast. METHODS: From January 2011 to December 2013, 188 patients underwent breast contrast-enhanced MRI; patients with unilateral and histopathologically confirmed breast lesions were included in this study; 123 patients had malignant lesions and 65 patients had benign tissue diagnoses. Breast semiautomatic vascular map detection was performed using Hessian matrix-based method and morphologic operators. Blood vessels detection was compared with radiologic interpretation findings to evaluate algorithm goodness. Increase in vascularity associated with ipsilateral cancer was also assessed. Chi square test was used to observe statistically significant difference. RESULTS: A total of 1315 blood vessels were identified using semiautomatic procedure; 1034 were correctly classified (78.7 %), 261 (19.8 %) were incorrectly classified, and 20 (1.5 %) were missing. A significant association was found between one-sided increased breast vascularity and ipsilateral malignancy (p < 0.001). CONCLUSIONS: In conclusion, detection of vascularity increase as risk factor for developing breast cancer could be performed with semiautomatic vascular mapping of contrast-enhanced MR imaging.

Immediate Adverse Reactions to Gadolinium-Based MR Contrast Media: A Retrospective Analysis on 10,608 Examinations.

Background and Purpose. Contrast media (CM) for magnetic resonance imaging (MRI) may determine the development of acute adverse reactions. Objective was to retrospectively assess the frequency and severity of adverse reactions associated with gadolinium-based contrast agents (GBCAs) injection in patients who underwent MRI. Material and Methods. At our center 10608 MRI examinations with CM were performed using five different GBCAs: Gd-BOPTA (MultiHance), Gd-DTPA (Magnevist), Gd-EOBDTPA (Primovist), Gd-DOTA (Dotarem), and Gd-BTDO3A (Gadovist). Results. 32 acute adverse reactions occurred, accounting for 0.3% of all administration. Twelve reactions were associated with Gd-DOTA injection (0.11%), 9 with Gd-BOPTA injection (0.08%), 6 with Gd-BTDO3A (0.056%), 3 with Gd-EOB-DTPA (0.028%), and 2 with Gd-DTPA (0.018%). Twenty-four reactions (75.0%) were mild, four (12.5%) moderate, and four (12.5%) severe. The most severe reactions were seen associated with use of Gd-BOPTA, with 3 severe reactions in 32 total reactions. Conclusion. Acute adverse reactions are generally rare with the overall adverse reaction rate of 0.3%. The most common adverse reactions were not severe, consisting in skin rash and hives.

Breast Contrast Enhanced MR Imaging: Semi-Automatic Detection of Vascular Map and Predominant Feeding Vessel.

PURPOSE: To obtain breast vascular map and to assess correlation between predominant feeding vessel and tumor location with a semi-automatic method compared to conventional radiologic reading. METHODS: 148 malignant and 75 benign breast lesions were included. All patients underwent bilateral MR imaging. Written informed consent was obtained from the patients before MRI. The local ethics committee granted approval for this study. Semi-automatic breast vascular map and predominant vessel detection was performed on MRI, for each patient. Semi-automatic detection (depending on grey levels threshold manually chosen by radiologist) was compared with results of two expert radiologists; inter-observer variability and reliability of semi-automatic approach were assessed. RESULTS: Anatomic analysis of breast lesions revealed that 20% of patients had masses in internal half, 50% in external half and the 30% in subareolar/central area. As regards the 44 tumors in internal half, based on radiologic consensus, 40 demonstrated a predominant feeding vessel (61% were supplied by internal thoracic vessels, 14% by lateral thoracic vessels, 16% by both thoracic vessels and 9% had no predominant feeding vessel-p<0.01), based on semi-automatic detection, 38 tumors demonstrated a predominant feeding vessel (66% were supplied by internal thoracic vessels, 11% by lateral thoracic vessels, 9% by both thoracic vessels and 14% had no predominant feeding vessel-p<0.01). As regards the 111 tumors in external half, based on radiologic consensus, 91 demonstrated a predominant feeding vessel (25% were supplied by internal thoracic vessels, 39% by lateral thoracic vessels, 18% by both thoracic vessels and 18% had no predominant feeding vessel-p<0.01), based on semi-automatic detection, 94 demonstrated a predominant feeding vessel (27% were supplied by internal thoracic vessels, 45% by lateral thoracic vessels, 4% by both thoracic vessels and 24% had no predominant feeding vessel-p<0.01). An excellent agreement between two radiologic assessments (k = 0.81) and between radiologic consensus and semi-automatic assessment (k = 0.80) was found to identify origin of predominant feeding vessel. An excellent reliability for semi-automatic assessment (Cronbach's alpha = 0.96) was reported. CONCLUSIONS: Predominant feeding vessel location was correlated with breast lesion location: internal thoracic artery supplied the highest proportion of breasts with tumor in internal half and lateral thoracic artery supplied the highest proportion of breasts with lateral tumor.

Color-doppler using contrast medium in evaluating the response to neoadjuvant treatment in patients with locally advanced breast carcinoma.

BACKGROUND: The aim of our study was to assess the color-Doppler ultrasound (CDU) pattern in the analysis of neoadjuvant preoperative treatment of patients with locally advanced breast carcinoma, improvement after injection of contrast medium (Levovist) and possible correlations between morphological and vascular aspects of the neoplasm and postoperative histopathological findings. MATERIALS AND METHODS: We studied 50 patients affected by locally advanced breast carcinoma (T3a e b-T4), using CDU before and after injection of Levovist, prior to and after neoadjuvant chemotherapeutic treatment. RESULTS: The use of Levovist for ultrasound examinations prior to treatment revealed a higher number of vascular signals in 94% of the lesions compared to the basic color-Doppler examination; in only 3 cases (6%) were no modifications observed after injection of the contrast medium. This finding was also evident after neoadjuvant treatment, as a greater number of vessels in 28 lesions were observed, in addition to residual vascularization in 9 patients in whom the basic color-Doppler examination demonstrated substantial avascularity. Histopathology revealed that this method was more sensitive in disclosing the presence of active neoplastic tissue. CONCLUSION: Color-Doppler ultrasound is the first step in assessing the efficacy of neochemotherapeutic treatment in patients affected by locally advanced breast carcinoma. Levovist increases sensitivity and improves the diagnostic precision, thus allowing for a better image of the vessels, which is an important index of the biological activity of the neoplasm, compared to the basic color-Doppler examination.

Early Assessment of Colorectal Cancer Patients with Liver Metastases Treated with Antiangiogenic Drugs: The Role of Intravoxel Incoherent Motion in Diffusion-Weighted Imaging.

PURPOSE: To assess the feasibility and effectiveness of quantitative intravoxel incoherent motion (IVIM) of Diffusion-weighted imaging (DWI) in the assessment of liver metastases treated with targeted chemotherapy agents. METHODS: 12 patients with unresectable liver metastases from colorectal cancer were enrolled and received neoadjuvant FOLFIRI (5-fluorouracil, leucovorin, irinotecan) plus bevacizumab therapy. DWI was performed for 36 metastases at baseline and after 14 days from starting the treatment. In addition to the basic IVIM metrics, the product between pseudo-diffusivity and perfusion fraction was considered as a descriptor roughly analogous to the flow. Median diffusion parameters of Region of Interest (ROI) were used as representative values for each lesion. Normalized parameters in comparison with the median value of spleen were also collected. The percentual change of the diffusion parameters was calculated. The response to chemotherapy was evaluated according the Response Evaluation Criteria in Solid Tumors (RECIST) as calculated on whole-body CT scan obtained three months after treatment. Mann Whitney test and Receiver operating characteristic (ROC) analysis were performed. RESULTS: 24 lesions were categorized as responding and 12 as not responding. There was no statistically significant difference among absolute and normalized diffusion parameters between the pretreatment and the post-treatment findings. Instead, the perfusion fraction (fp) values showed a statistical difference between responder and non-responder lesions: sensitivity and specificity of fp variation was 62% and 93%, respectively. CONCLUSIONS: IVIM parameters represent a valuable tool in the evaluation of the anti-angiogenic therapy in patients with liver metastases from colorectal cancer. A percentage change of fp represents the most effective DWI marker in the assessment of tumor response.

Integration of DCE-MRI and DW-MRI Quantitative Parameters for Breast Lesion Classification.

OBJECTIVE: The purpose of our study was to evaluate the diagnostic value of an imaging protocol combining dynamic contrast-enhanced MRI (DCE-MRI) and diffusion-weighted MRI (DW-MRI) in patients with suspicious breast lesions. MATERIALS AND METHODS: A total of 31 breast lesions (15 malignant and 16 benign proved by histological examination) in 26 female patients were included in this study. For both DCE-MRI and DW-MRI model free and model based parameters were computed pixel by pixel on manually segmented ROIs. Statistical procedures included conventional linear analysis and more advanced techniques for classification of lesions in benign and malignant. RESULTS: Our findings indicated no strong correlation between DCE-MRI and DW-MRI parameters. Results of classification analysis show that combining of DCE parameters or DW-MRI parameter, in comparison of single feature, does not yield a dramatic improvement of sensitivity and specificity of the two techniques alone. The best performance was obtained considering a full combination of all features. Moreover, the classification results combining all features are dominated by DCE-MRI features alone. CONCLUSION: The combination of DWI and DCE-MRI does not show a potential to dramatically increase the sensitivity and specificity of breast MRI. DCE-MRI alone gave the same performance as in combination with DW-MRI.

Procedures for location of non-palpable breast lesions: a systematic review for the radiologist.

Accurate location of small breast lesions is mandatory for proper surgical management. The purpose of this article is systematically review procedures used to locate non-palpable breast lesions, including a description of the current status, advantages, and disadvantages for each technique. A total of 47 articles were finally included: 7 articles for the wire location technique, 5 articles for the radioguided location technique, 13 articles that compare wire location with radioguided location, 3 articles for the carbon location technique, 2 articles that compare wire location with carbon location, and 17 articles for the clip location technique. The success of location and the clear margin are reported for each location technique and for the separate articles included; clip migration shift, also, is reported for the clip location technique. Odds ratio with related 95 % confidence intervals were also calculated for successful location. Comparative analysis or meta-analysis for all the different breast lesion location techniques is missing. Prospective investigations and randomized investigations for homogeneous populations are still needed to determine which is the most cost-effective modality among those used to date.

Risk management in magnetic resonance: failure mode, effects, and criticality analysis.

The aim of the study was to perform a risk management procedure in "Magnetic Resonance Examination" process in order to identify the critical phases and sources of radiological errors and to identify potential improvement projects including procedures, tests, and checks to reduce the error occurrence risk. In this study we used the proactive analysis "Failure Mode Effects Criticality Analysis," a qualitative and quantitative risk management procedure; has calculated Priority Risk Index (PRI) for each activity of the process; have identified, on the PRI basis, the most critical activities and, for them, have defined improvement projects; and have recalculated the PRI after implementation of improvement projects for each activity. Time stop and audits are performed in order to control the new procedures. The results showed that the most critical tasks of "Magnetic Resonance Examination" process were the reception of the patient, the patient schedule drafting, the closing examination, and the organization of activities. Four improvement projects have been defined and executed. PRI evaluation after improvement projects implementation has shown that the risk decreased significantly following the implementation of procedures and controls defined in improvement projects, resulting in a reduction of the PRI between 43% and 100%.

Post-treatment fistulas in patients with rectal cancer: MRI with rectal superparamagnetic contrast agent.

MRI is the standard modality in the pre- and post-treatment evaluation of patients with rectal cancer, particularly in those cases with locally advanced disease. We routinely employ a superparamagnetic iron oxide (SPIO) contrast enema to distend the rectal lumen and achieve maximal tumor-to-lumen contrast gradient. This practice also allowed the identification of a fistula in 24% of patients treated for rectal cancer. Contrast agent-related low intensity signal could be seen filling the tract and eventually opacifying surrounding organs (i.e., vagina) or collections (i.e., presacral abscess). Fistula formation after radiochemotherapy and surgery for rectal cancer is not uncommon. MRI with dark lumen contrast enema allows an effective demonstration of this complication in a high number of patients.