A mimicker of inflammatory breast carcinoma: Lupus mastitis and evolving imaging features.

Rare case of lupus mastitis in a 58-year-old female with discoid lupus erythematosus presented with fever, left breast swelling, and painful palpable lesion. Accurate imaging and histopathologic evaluation allowed for appropriate management and regression of breast findings with hydroxychloroquine treatment, emphasizing the need to avoid unnecessary biopsies and surgeries.

Malignant versus benign mediastinal lesions: quantitative assessment with diffusion weighted MR imaging.

OBJECTIVES: We aimed to evaluate the performance of diffusion-weighted magnetic resonance imaging in differentiating malignant from benign mediastinal lesions. METHODS: Fifty-three mediastinal lesions were examined with T1- and T2-weighted (W) conventional images. Then, two diffusion-weighted images were obtained with b = 0 and 1000 s/mm² values and apparent diffusion coefficients (ADC) were calculated. The statistical significance of differences between measurements was tested using the Student-t test. RESULTS: The mean ADC of malignant lesions was significantly lower than that of the benign masses (p < 0.001). The cut-off value of ≤ 1.39 × 10(-3) mm²/s indicated a malignant lesion with a sensitivity of 95% and specificity of 87%. CONCLUSION: Diffusion-weighted imaging may be helpful in differentiating benign from malignant mediastinal masses.

Intravoxel incoherent motion magnetic resonance imaging for breast cancer: A comparison with molecular subtypes and histological grades.

PURPOSE: The purpose of this paper is to investigate whether the IVIM parameters (D, D *, f) helps to determine the molecular subtypes and histological grades of breast cancer. METHODS: Fifty-one patients with breast cancer were included in the study. All subjects were examined by 3 T Magnetic Resonance Imaging (MRI). Diffusion-weighted imaging (DWI) was undertaken with 16 b-values. IVIM parameters [D (true diffusion coefficient), D* (pseudo-diffusion coefficient), f (perfusion fraction)] were calculated. Histopathological reports were reviewed to histological grade, histological type, and immunohistochemistry. IVIM parameters of tumors with different histological grades and molecular subtypes were compared. RESULTS: D* and f were significantly different between molecular subtypes (p = 0.019, p = 0.03 respectively). D* and f were higher in the HER-2 group and lower in Triple negative (-) group (D*:36.8 × 10-3 ± 5.3 × 10-3 mm2/s, f:29.5%, D*:29.8 × 10-3 ± 5.6 × 10-3 mm2/s, f:21.5% respectively). There was a significant difference in D* and f between HER-2 and Triple (-) subgroups (p = 0,028, p = 0.024, respectively). D* was also significantly different between the HER-2 group and the Luminal group (p = 0,041). While histological grades increase, D and f values tend to decrease, and D* tends to increase. While the Ki-67 index increases, D* and f values tend to increase, and D tend to decrease. CONCLUSION: D* and f values measured with IVIM imaging were useful for assessing breast cancer molecular subtyping. IVIM imaging may be an alternative to breast biopsy for sub-typing of breast cancer with further research.

Diffusion-weighted imaging in the differential diagnosis of cystic lesions of the pancreas.

OBJECTIVE: The purpose of our study was to evaluate the value of diffusion-weighted imaging (DWI) in the differential diagnosis of pancreatic cysts. SUBJECTS AND METHODS: Forty-two cysts (16 simple cysts, seven pseudocysts, five abscesses, three hydatid cysts, two serous cystadenomas, three mucinous cystadenomas, two mucinous cystadenocarcinomas, four cystic degenerated adenocarcinomas) were included in this prospective study. Single-shot spin-echo echo-planar DWI was performed with three b factors (0, 500, and 1,000 s/mm(2)), and apparent diffusion coefficients (ADCs) were calculated. On DWI, the signal intensity of the cysts was visually compared with the signal intensity of the pancreas parenchyma. For the quantitative evaluation, cyst-to-pancreas signal intensity ratios, ADC of the lesions, and cyst-to-pancreas ADC ratios were compared. RESULTS: On visual evaluation, all cystic lesions were hyperintense on DWI with b factors of 0 and 500 s/mm(2). On DWI with a b factor of 1,000 s/mm(2), all abscesses and hydatid and neoplastic cysts were hyperintense, whereas most of the simple and pseudocysts were isointense. Quantitatively, with b factors of 0 and 500 s/mm(2), no statistical significance was achieved. With a b factor of 1,000 s/mm(2), the cyst-to-pancreas signal intensity ratios of the abscesses and hydatid and neoplastic cysts were significantly higher than those of the simple cysts and pseudocysts. Setting the cutoff value of signal intensity ratio at 1.9, the cyst-to-pancreas signal intensity ratio had a sensitivity of 70% and a specificity of 90% for differentiating abscesses, hydatid cysts, and neoplastic cysts from simple cysts and pseudocysts. The ADC and the ADC ratios of the abscesses, hydatid cysts, and neoplastic cysts were significantly lower than those of the simple cysts and pseudocysts. CONCLUSION: DWI may help in the differential diagnosis of pancreatic cysts.

Dynamic contrast enhanced MRI in the differential diagnosis of adrenal adenomas and malignant adrenal masses.

OBJECTIVE: To evaluate the value of dynamic MR imaging in the differential diagnosis of adrenal adenomas and malignant tumors, especially in cases with atypical adenomas. MATERIALS AND METHODS: Sixty-four masses (48 adenomas, 16 malignant tumors) were included in this prospective study. Signal loss of masses was evaluated using chemical shift MR imaging. Five dynamic series of T1-weighted spoiled gradient echo (FFE) images were obtained, with the acquisition starting simultaneously with i.v. contrast administration (0-100 s) followed by a T1-weighted FFE sequence in the late phase (5th minute). Contrast enhancement patterns in the early (25th second) and late (5th minute) phase images were evaluated. For the quantitative evaluation, signal intensity (SI)-time curves were obtained according to the SIs on the 0th, 25th, 50th 75th and 100th second. Also, the wash-in rate, maximum relative enhancement, time-to-peak, and wash-out of contrast at 100 s of masses in both groups were calculated. The statistical significance was determined by Mann-Whitney U test. To evaluate the diagnostic performance of the quantitative tests, receiver operating characteristic (ROC) analysis was performed. RESULTS: Chemical shift MR imaging was able to differentiate 44 out of 48 adenomas (91.7%) from non-adenomas. The 4 adenomas (8.3%) which could not be differentiated from non-adenomas by this technique did not exhibit signal loss on out-of-phase images. With a cut-off value of 30, SI indices of adenomas had a sensitivity of 93.8%, specificity of 100% and a positive predictive value of 100%. On visual evaluation of dynamic MR imaging, early phase contrast enhancement patterns were homogeneous in 75% and punctate in 20,83% of the adenomas; while patchy in 56.25% and peripheral in 25% of the malignant tumors. On the late phase images 58.33% of the adenomas showed peripheral ring-shaped enhancement and 10.41% showed heterogeneous enhancement. All of the malignant masses showed heterogeneous enhancement. At the 25th second, the SIs and wash-in rates of the adenomas were significantly higher than those of the malignant masses (p=0.010). Time-to-peak enhancement of the malignant masses was significantly longer than that of the adenomas. With a cut-off value of 52.85 s, the time-to-peak enhancement had 87.5% sensitivity and 80% specificity. CONCLUSION: Chemical shift MR has a high sensitivity and specificity in the differential diagnosis of adenomas and malignant adrenal masses. However, taking into consideration only the atypical adenomas, chemical shift MRI is of no diagnostic value. Although the diagnostic value of dynamic MRI is lower than chemical shift MRI, in the atypical cases contrast enhancement patterns and time-to-peak and wash-in rates derived from SI-time curve of dynamic MRI give are contributory to the results of chemical shift MRI.

Color Doppler ultrasonographic flow parameters in the differentiation of benign and malignant causes of omental thickening.

OBJECTIVE: The purpose of the study was to determine if color Doppler ultrasonographic (US) quantitative flow parameters are valuable to differentiate malignant peritoneal or omental involvement from benign causes. MATERIALS AND METHODS: Twenty-six consecutive patients with peritoneal or omental thickening detected by gray scale US, computed tomography, and magnetic resonance underwent color Doppler US examinations. All the Doppler signal waveforms were recorded, and resistive (RI) and pulsatility indices (PI) were calculated automatically by the US machine. In the statistical analysis of RI and PI, unpaired t test was used. A P < 0.05 was considered significant. RESULTS: Nineteen of 20 malignant and 5 of 6 benign lesions had detectable color Doppler US pulsatile flow signals. The mean RI and PI values were 0.6260 and 1.36, respectively, for the benign group and 0.5384 and 1.4147, respectively, for the malignant group. For malignant lesions, mean RI was lower (P = 0.0796), and mean PI was higher (P = 0.9183) than benign lesions. However, these differences were not statistically significant. CONCLUSIONS: Overlapping RI and PI values in benign and malignant omental lesions limit the clinical value of flow parameters in the differentiation of benign and malignant involvement of the omentum.

Unusual magnetic resonance image of an insulinoma with extensive desmoplastic reaction.

CONTEXT: Unlike other islet-cell tumors, insulinomas are usually benign. Most insulinomas have a high signal intensity on T2-weighted images and a low signal intensity on T1-weighted images, and are hyperintense on immediate post-gadolinium images. However, in rare cases, insulinomas may be hypointense on T2-weighted images and on immediate post-gadolinium images, mimicking a ductal adenocarcinoma. CASE REPORT: We present a case of a surgically proven insulinoma which was hypointense on both T2-weighted and immediate post-gadolinium T1-weighted images, but hyperintense on late phase T1-weighted images. Histopathological examination of the surgical specimen revealed a prominent desmoplastic reaction which accounted for the low signal on T2-weighted images and the contrast enhancement pattern. Delayed contrast enhancement reflects the desmoplastic component of this tumor. CONCLUSIONS: Insulinomas with an extensive desmoplastic reaction may appear hypointense on T2-weighted images with minimal enhancement on immediate post-gadolinium images. Late phase fat-suppressed T1-weighted post-gadolinium images may be useful in the detection of such tumors.

The Performance of Radiographic Criteria for Bone Malignancy When Applied to Computed Tomography and Magnetic Resonance Imaging.

BACKGROUND: The conventional radiologic features that differentiate benign from malignant bone lesions were originally described using radiography (x-ray [XR]). When evaluating sectional imaging studies such as magnetic resonance imaging (MRI) and computed tomography (CT), one may apply these principles to identify malignant bone lesions. The aim of this study was to evaluate the performances of these radiographic features for detecting malignity when applied to CT and MRI. MATERIALS AND METHODS: This retrospective study was approved by our institutional ethical board. Thirty-nine patients with histopathologic proof of a high-grade bone malignancy and preoperative imaging data obtained with a minimum of two different modalities were included in the study. Four radiologists reviewed the images and scored the lesions for distinctness of margins, presence and type of periosteal reaction, matrix mineralization, and presence of soft tissue mass. The average score for each modality was then tested for accuracy with regard to the histopathology. RESULTS: When lesion margins were considered, XR was the best modality to detect a high-grade malignancy. MRI, especially postcontrast T1-weighted sequence, was the least helpful in this regard. There was no significant difference between CT and XR and between CT and MRI. When the periosteal reaction was considered, XR was the best modality to detect the malignant type of periosteal reaction. In this regard, MRI and CT were misleading; either by not detecting or undergrading periosteal reaction. MRI was the best modality to detect soft tissue mass. CONCLUSION: Conventional imaging criteria for bone malignancy can be misleading when applied to MRI or CT. When cross-sectional imaging features contradict those from XR, the latter should be the guide for clinical management.

Diffusion-weighted imaging in the differential diagnosis of simple and hydatid cysts of the liver.

OBJECTIVE: The purpose of our study was to evaluate the value of diffusion-weighted imaging (DWI) in the differential diagnosis of simple and hydatid cysts of the liver, particularly in the completely liquid type of hydatid cyst. SUBJECTS AND METHODS: Eighty-two cysts (43 simple cysts, 39 hydatid cysts) were included in this prospective study. DWI was performed using a breath-hold single-shot echo-planar spin-echo sequence, and apparent diffusion coefficients (ADCs) were calculated. On DW trace images, the signal intensity of cysts was visually compared with the signal intensity of the liver using a 3-point scale: 0, isointense; 1, moderately hyperintense; and 2, significantly hyperintense. Quantitatively, signal intensity of the cysts, cyst-to-liver signal intensity ratios, ADC of the cysts, and cyst-to-liver ADC ratios were compared between the groups. The statistical significance was determined using the Mann-Whitney U test. RESULTS: On trace DWI (b = 1,000 s/mm2), most hydatid cysts (37/39, 95%) were hyperintense, whereas most simple cysts (40/43, 93%) were isointense with the liver. Three simple cysts (7%) were moderately hyperintense and two hydatid cysts (5%) were isointense. Quantitatively, both the signal intensity and cyst-to-liver signal intensity ratio of the hydatid cysts were significantly higher than those for simple cysts (p < 0.001). The cutoff value at 1.5 yielded a sensitivity of 77%, a specificity of 86%, and positive predictive value of 83% for the cyst-to-liver signal intensity ratio. The ADC and cyst-to-liver ADC ratio of the hydatid cysts were significantly lower than those of simple cysts (p < 0.005). For the completely liquid type in particular, we observed statistically significant differences in signal intensity, signal intensity ratio, ADC, and ADC ratios from those of simple cysts (p < 0.005). With a cutoff value of 1.5, signal intensity ratio had a sensitivity of 81%, specificity of 86%, and positive predictive value of 74%. CONCLUSION: DWI may help in the differential diagnosis of hydatid and simple cysts of the liver.

Diagnostic Accuracy of Dynamic Contrast Enhanced Magnetic Resonance Imaging in Characterizing Lung Masses.

BACKGROUND: Imaging plays a critical role not only in the detection, but also in the characterization of lung masses as benign or malignant. OBJECTIVES: To determine the diagnostic accuracy of dynamic magnetic resonance imaging (MRI) in the differential diagnosis of benign and malignant lung masses. PATIENTS AND METHODS: Ninety-four masses were included in this prospective study. Five dynamic series of T1-weighted spoiled gradient echo (FFE) images were obtained, followed by a T1-weighted FFE sequence in the late phase (5th minutes). Contrast enhancement patterns in the early (25th second) and late (5th minute) phase images were evaluated. For the quantitative evaluation, signal intensity (SI)-time curves were obtained and the maximum relative enhancement, wash-in rate, and time-to-peak enhancement of masses in both groups were calculated. RESULTS: The early phase contrast enhancement patterns were homogeneous in 78.2% of the benign masses, while heterogeneous in 74.4% of the malignant tumors. On the late phase images, 70.8% of the benign masses showed homogeneous enhancement, while most of the malignant masses showed heterogeneous enhancement (82.4%). During the first pass, the maximum relative enhancement and wash-in rate values of malignant masses were significantly higher than those of the benign masses (P = 0.03 and 0.04, respectively). The cutoff value at 15% yielded a sensitivity of 85.4%, specificity of 61.2%, and positive predictive value of 68.7% for the maximum relative enhancement. CONCLUSION: Contrast enhancement patterns and SI-time curve analysis of MRI are helpful in the differential diagnosis of benign and malignant lung masses.

Diffusion-weighted Magnetic Resonance Imaging in the Differential Diagnosis of Benign and Metastatic Malignant Pleural Thickening.

PURPOSE: Imaging plays a critical role not only in detection but also in characterization of pleural thickening as benign or malignant. The aim of the study was to investigate the value of diffusion-weighted (DW) imaging in the differential diagnosis of benign and metastatic malignant pleural thickening. MATERIALS AND METHODS: Thirty-four patients with 64 pleural foci of nodular thickening (47 metastatic malignant and 17 benign) were included in this prospective study. DW imaging was performed using a breath-hold single-shot spin-echo echo-planar sequence. Two different apparent diffusion coefficient (ADC1,2) maps were obtained with different b factors (ADC1 reconstructed from b factors of 0 and 650 mm/s and ADC2 reconstructed from b factors of 0 and 1000 mm/s), and ADCs were calculated. Quantitatively, ADCs were compared between the groups, and the optimal cutoff value was found by using receiver operating characteristic curve analysis. RESULTS: Quantitatively, differences in signal intensities on DW trace images with b factors of 650 and 1000 mm/s were not statistically significant. The ADC1 and ADC2 of the metastatic malignant thickening were significantly lower than those of benign ones [mean ADC1 was 1.37±0.65×10 mm/s for metastatic malignant thickening and 2.11±0.69×10 mm/s for benign thickening (P=0.045); ADC2 was 1.06±0.56×10 mm/s for metastatic malignant thickening and 1.56±0.71×10 mm/s for benign thickening (P=0.038)]. However, because of the ADC overlap between malignant and benign disease, a sufficiently discriminative cutoff value could not be defined by the receiver operating characteristic curve analysis. CONCLUSION: Despite fair sensitivity and specificity, DW imaging may serve as a complementary tool that improves the differential diagnosis of pleural thickening.

MRI patterns in orbital malignant lymphoma and atypical lymphocytic infiltrates.

OBJECTIVE: To evaluate the potential of MRI in differentiating between malignant lymphomas and atypical lymphocytic infiltrates in the orbit. MATERIALS AND METHODS: MRI, clinical and histopathological findings in 30 patients presenting with orbital lymphoproliferative diseases (malignant lymphoma and atypical lymphocytic infiltrates) were evaluated. RESULTS: MRI detected 28 out of 30 (93%) orbital lymphoid tumors. Seven out of eight (87.5%) atypical lymphocytic infiltrates and 21/22 (95.4%) of malignant lymphomas were detected. One conjunctival malignant lymphoma and one conjunctival atypical lymphocytic infiltrate were missed. Only malignant lymphoma lesions were hyperintense compared to the extraocular muscles on precontrast and postcontrast T1-weighted images. The lacrimal duct was involved only with malignant lymphoma. Bilateral disease was more likely to be malignant lymphoma. Intraconal lesions were more likely to be associated with lesions elsewhere. No malignant lymphoma involved the extraconal fat. Only intraconal atypical lymphocytic infiltrates had indistinct margins. CONCLUSION: In the orbit, MRI features alone may not allow clear-cut differentiation of malignant lymphomas from atypical lymphocytic infiltrates. However, certain imaging features increase the likelihood of distinguishing them. MRI may miss conjunctival disease. Both orbits should be imaged when orbital lymphoid disease is a probability. The presence of intraconal disease should prompt a search for lesions elsewhere. The use of a head coil instead of a superficial coil may be advantageous by eliminating coil shine effect and allowing evaluation of both orbits. Comparison of lesion signal to extraocular muscle signal appears to be a better alternative than cerebral gray matter or periorbital fat in differentiating malignant lymphoma from atypical lymphocytic infiltrates. Since imaging findings overlap, histopathological diagnosis is necessary in all cases.

ROI measurement of the signal intensity of precentral cortex in the normal brain.

OBJECTIVE: It has recently been described that perirolandic cortex generally had a low signal intensity (SI) in neurologically normal brain. The aim of this study was to confirm this finding by an objective quantitative study. MATERIALS AND METHODS: Turbo fluid attenuated inversion recovery (FLAIR) magnetic resonance (MR) images of 24 neurologically normal patients were evaluated retrospectively. Signal intensity measurements of the precentral and superior frontal cortices (SFCs) were obtained at a manually traced irregular region-of-interest (ROI). t-Test for paired samples was used to evaluate the significance of differences between signal intensity measurements. RESULTS: Mean signal intensities of precentral and superior frontal cortices were 349.5 and 380.7, respectively, on the right, and 351.7 and 374.1 on the left hemisphere. The difference between the mean signal intensities of the side-matched precentral and superior frontal cortices was statistically significant (P < 0.001). CONCLUSION: Low signal intensity of the precentral cortex (PCC) in normal brain on turbo FLAIR images is an objective finding, confirmed by ROI measurement.

Driven equilibrium (drive) MR imaging of the cranial nerves V-VIII: comparison with the T2-weighted 3D TSE sequence.

PURPOSE: The aim of this study is to evaluate the efficacy of the driven equilibrium radio frequency reset pulse (DRIVE) on image quality and nerve detection when used in adjunction with T2-weighted 3D turbo spin-echo (TSE) sequence. MATERIALS AND METHODS: Forty-five patients with cranial nerve symptoms referable to the cerebellopontine angle (CPA) were examined using a T2-weighted 3D TSE pulse sequence with and without DRIVE. MR imaging was performed on a 1.5-T MRI scanner. In addition to the axial resource images, reformatted oblique sagittal, oblique coronal and maximum intensity projection (MIP) images of the inner ear were evaluated. The nerve identification and image quality were graded for the cranial nerves V-VIII as well as inner ear structures. These structures were chosen because fluid-solid interfaces existed due to the CSF around (the cranial nerves V-VIII) or the endolymph within (the inner ear structures). Statistical analysis was performed using the Wilcoxon test. P < 0.05 was considered significant. RESULTS: The addition of the DRIVE pulse shortens the scan time by 25%. T2-weighted 3D TSE sequence with DRIVE performed slightly better than the T2-weighted 3D TSE sequence without DRIVE in identifying the individual nerves. The image quality was also slightly better with DRIVE. CONCLUSION: The addition of the DRIVE pulse to the T2-weighted 3D TSE sequence is preferable when imaging the cranial nerves surrounded by the CSF, or fluid-filled structures because of shorter scan time and better image quality due to reduced flow artifacts.

Ophthalmic artery color Doppler ultrasonography in mild-to-moderate preeclampsia.

OBJECTIVE: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. METHODS: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. RESULTS: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. CONCLUSION: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia.

Hepatic and splenic uptake of Tc-99m HDP in multiple myeloma: additional findings on Tc-99m MIBI and Tc-99m sulfur colloid images.

The authors present a case of multiple myeloma with intense hepatic and splenic uptake on Tc-99m HDP bone scan and discuss its clinical implications and possible uptake mechanisms. Tc-99m MIBI and Tc-99m sulfur colloid were used to demonstrate bone marrow involvement and focal lesions of multiple myeloma.

"Double imaging" for the diagnostic work-up of alveolar soft part sarcoma with Tc-99m MIBI.

The authors report a case of alveolar soft-part sarcoma with lung metastases demonstrated by "double imaging" with Tc-99m HDP and Tc-99m MIBI. The tumor originated in the soft tissue with direct invasion to the right scapula, which was hypoactive on bone scan and hyperactive on Tc-99m MIBI images. A focus of dense accumulation of Tc-99m MIBI in the lungs, suggesting metastasis was also demonstrated.

Spontaneously T1-hyperintense lesions of the brain on MRI: a pictorial review.

In this work, the brain lesions that cause spontaneously hyperintense T1 signal on MRI were studied under seven categories. The first category includes lesions with hemorrhagic components, such as infarct, encephalitis, intraparenchymal hematoma, cortical contusion, diffuse axonal injury, subarachnoid hemorrhage, subdural and epidural hematoma, intraventricular hemorrhage, vascular malformation and aneurysm, and hemorrhagic neoplasm. The second category includes protein-containing lesions, such as colloid cyst, craniopharyngioma, Rathke's cleft cyst, and atypical epidermoid. The third category includes lesions with fatty components, such as lipoma, dermoid, and lipomatous meningioma. Lesions with calcification or ossification, such as endocrine-metabolic disorder, calcified neoplasm, infection, and dural osteoma, constitute the fourth category, whereas the fifth category includes lesions with other mineral accumulation, such as acquired hepatocerebral degeneration and Wilson disease. The sixth category includes melanin-containing lesions, such as metastasis from melanoma and leptomeningeal melanosis. The last category is the miscellaneous group, which includes ectopic neurohypophysis, chronic stages of multiple sclerosis, and neurofibromatosis type I. The above-mentioned lesions are presented with their typical T1-hyperintense images, and the underlying reasons for those appearances in magnetic resonance imaging are discussed.

Comparison of the diagnostic performances of diffusion parameters in diffusion weighted imaging and diffusion tensor imaging of breast lesions.

PURPOSE: To evaluate the diagnostic efficiency of the diffusion parameters measured by conventional diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) for discrimination of malignant breast lesions from benign lesions and the normal breast. MATERIALS AND METHODS: The study included 52 women with 55 breast lesions (30 malignant, 25 benign). DTI and DWI were performed complementary to dynamic contrast MRI at 3T. Apparent diffusion coefficient (ADC) of DWI, mean diffusivity (MD) and fractional anisotropy (FA) values of DTI were measured for lesions and contralateral breast parenchyma in each patient. We used b factors of 0, 50, 850, 1000 and 1500 s/mm(2) for DWI and b 0 and 1000 s/mm(2) for DTI. ADC, MD and FA values were compared between malignant and benign lesions, and the normal parenchyma by univariate and multivariate analyses. RESULTS: Diffusion parameters showed no difference according to menopausal status in the normal breast. ADC and MD values of the malignant lesions were significantly lower than benign lesions and normal parenchyma (p=0.001). The FA showed no statistical significance. With the cut-off values of ≤ 1.23 × 10(-3)mm(2)/s (b 0-1000 s/mm(2)) and ≤ 1.12 × 10(-3)mm(2)/s (b 0-1500 s/mm(2)), ADC showed 92.85% and 96.15% sensitivity; 72.22% and 73.52% PPV, respectively. With a cut-off value of ≤ 1.27 × 10(-3)mm(2)/s (b 1000 s/mm(2)), MD was 100% sensitive with a PPV of 65.90%. Comparing the diagnostic performance of the parameters in DTI with DWI, we obtained similar efficiency of ADC with b values of 0,1000 and 0,1500 s/mm(2) and MD with a b value of 0, 1000 s/mm(2) (AUC = 0.82 ± 0.07). CONCLUSION: ADC of DWI and MD of DTI values provide significant discriminative factors for benign and malignant breast lesions. FA measurement was not discriminative. Supported with clinical and dynamic contrast MRI findings, DWI and DTI findings provide significant contribution to the final radiologic decision.