Several MR imaging features might be used for detecting triple-negative breast cancer.

No abstract

Skull metastases are malignant bone tumors which are increasing in incidence. The objectives of this study were to characterize the MR imaging features, locations, and extent of metastatic skull tumors to determine the frequency of the symptomatic disease, and to assess patient outcomes. Between September 2002 and March 2008, 175 patients undergoing routine head MR imaging were found to have metastatic skull tumors. Contrast-enhanced study with fat suppression was used in some cases when required. Classification of metastases was simplified to three yes/no questions: first, with regard to location (either in the calvarium or in the cranial base); second, with regard to distribution within the plane of the cranial bone (either “circumscribed” meaning clearly demarcated and confined to one bone, or “diffuse” and likely to spread across a suture to another bone); and third, with regard to invasion (“intraosseous” in cranial bones only, or “invasive” spreading from the skull, either out into the scalp or inward to the dura and perhaps further in). Primary sites were breast cancer (55%), lung cancer (14%), prostate cancer (6%), malignant lymphoma (5%), and others (20%). The mean time from primary diagnosis to skull metastasis diagnosis was 71 months for cases of breast cancer, 26 months for prostate cancer, 9 months for lung cancer, and 4 months for malignant lymphoma. Calvarial circumscribed intraosseous metastases were found most frequently (27%). The patients were mainly asymptomatic. However, some patients suffered from local pain or cranial nerve palsies that harmed their quality of life. Treatment, mainly for symptomatic cases, was by local or whole-skull irradiation. Metastatic skull tumors are not rare, and most are calvarial circumscribed intraosseous tumors. MR images contribute to understanding their type, location, and multiplicity, and their relationship to the brain, cranial nerves, and dural sinuses. Radiation therapy improved the QOL of patients with neurological symptoms.

Purpose:To investigate the effect of gadolinium (Gd)-DTPA on the apparent diffusion coefficient (ADC) of breast carcinoma and to analyze the relationship between pre/postcontrast ADC and the degree of contrast enhancement. Materials and Methods:Nineteen histopathologically confirmed breast carcinomas (mean size ϭ 22 mm) were analyzed. Their ADCs before and after contrast administration were measured. The contrast-to-noise ratios (CNRs) of the tumors were measured on fat-suppressed 3D T1-weighted images in precontrast, early, and late postcontrast phases. These results were correlated with the measured ADC values.Results: A significant decrease in the measured ADC was noted after contrast administration (Ϫ23%, P ϭ 0.01). Lesions with relatively high ADC before contrast (Ͼ1.3 ϫ 10 Ϫ3 mm 2 /sec; n ϭ 12) demonstrated a larger degree of ADC reduction (mean 34%) than lesions with low ADC (Յ1.3 ϫ 10 Ϫ3 mm 2 /sec; n ϭ 7) (mean 4.5%). When an early postcontrast image was used as a surrogate marker of malignant potential, we found a significant inverse correlation with postcontrast ADC (␥ ϭ Ϫ0.57, P ϭ 0.02). Conclusion:Postcontrast ADC exhibited lower values than precontrast ADC, which is thought to reflect suppression of the microperfusion-induced effect on diffusion-weighted imaging. Postcontrast ADC may be a better indicator than precontrast ADC to reflect malignant potential of tumors.

MR imaging was the most accurate breast imaging modality for the tumor exten of breast cancer, although MR imaging had a substantial of risk of overestimation. MR imaging, MDCT and US can complement MMG for the preoperative evaluation of patients who are candidates for breast-conserving surgery.

Two technical challenges must be overcome before brain fiber tracking with diffusion-tensor magnetic resonance (MR) imaging can be applied to clinical practice: Imaging time must be shortened, and image distortion must be minimized. Single-shot echo-planar MR imaging with parallel imaging technique enabled both objectives to be accomplished. Twenty-three consecutive patients with brain tumors underwent MR imaging with a 1.5-T whole-body MR system. Fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. This diffusion-tensor MR imaging method with the parallel imaging technique allows clinically feasible brain fiber tracking.

Purpose:To investigate the histopathological characteristics of breast carcinomas with strong high-signal intensity (SHi) on T2-weighted (T2W) MR images (T2-SHi), and discuss the differential diagnosis between T2-SHi breast carcinomas and T2-SHi fibroadenomas. Materials and Methods:Thirty of 480 breast carcinomas examined by MRI were defined as tumors with T2-SHi (defined as homogeneous higher signal intensity (SI) compared to surrounding normal breast tissue on fat-suppressed T2W imaging (T2WI). They included eight mucinous and 22 nonmucinous carcinomas. The histopathological characteristics of T2-SHi breast carcinomas, their signal-to-noise ratios (SNRs) on T2WI, contrast-enhancement patterns, and morphology were compared with those of 22 non-T2-SHi breast carcinomas and 19 T2-SHi fibroadenomas. Results:In nonmucinous carcinomas T2-SHi was attributable to a mixture of background matrix, a higher proportion of cells than stroma, abundant cytoplasm, edematous stroma, and hemorrhage. The significantly high SNR (mean ϭ 75) and enhancing internal septations seen in mucinous carcinomas, and the washout phenomenon, irregular border, absence of internal septation, and rim enhancement seen in nonmucinous carcinomas provide useful information for differentiating these tumors from T2-SHi fibroadenomas. Conclusion:A mixture of several histopathological characteristics was associated with T2-SHi breast carcinomas. The combined information from T2WI and contrast-enhanced (CE) imaging may help distinguish T2-SHi breast carcinomas from T2-SHi fibroadenomas. BREAST MRI is now widely used to diagnose and characterize suspected breast lesions identified by mammography and ultrasonography. Contrast-enhanced (CE) breast MRI has a high sensitivity (approximately 90%) but lower specificity (37-86%) for detecting breast carcinoma (1-9). Attempts have been made to increase its specificity, and some studies have indicated that careful analysis of T2-weighted images (T2WI) can aid in establishing a differential diagnosis (10 -15).T2WI are typically used to identify and characterize cysts. Typical breast carcinomas have shorter T2 relaxation times and display lower signal intensity (SI) on T2WI than benign lesions (16,17). However, many benign lesions and some carcinomas, including mucinous (colloid) carcinomas (18), have a long T2 relaxation time and are occasionally difficult to distinguish from cysts on T2WI alone. The SI of fibroadenomas on T2WI, and the histopathological correlation have been analyzed. Myxoid and edematous fibroadenomas yield strong high-SI (SHi) on T2WI (T2-SHi) (19,20). However, few studies have examined the correlation between SI on T2WI and histopathology of carcinoma.Since it remains to be determined why some breast carcinomas other than mucinous carcinomas display T2-SHi, we investigated the histopathological characteristics of breast carcinomas with T2-SHi. We discuss the diagnostic utility of the combined information provided by T2-SHi and the enhancement patterns and morphology on CE images for differentiat...

BACKGROUND AND PURPOSE:The Vim and VPL are important target regions of the thalamus for DBS. Our aim was to clarify the anatomic locations of the ventral thalamic nuclei, including the Vim and VPL, on MR imaging.