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61.

Background

Just as mammographic breast density influences mammographic sensitivity, the degree of background enhancement in breast magnetic resonance imaging (MRI) may influence the sensitivity of breast MRI. The purpose of this study is to assess the influence of background enhancement on the accuracy of breast cancer extent assessment using MRI and to assess the correlation between the accuracy of breast cancer extent assessment and the kinetic analysis of background enhancement in dynamic contrast-enhanced MRI.

Methods

Seventy bilateral breast MRI examinations were evaluated to assess the extent of a known primary tumor. Background enhancement was classified into four categories by visual assessment: minimal, mild, moderate, and marked, in the early dynamic phase and in the late dynamic phase. The correlation of the results with histological findings was examined.

Results

Background enhancement grade showed a significant tendency to increase during dynamic contrast-enhanced MRI. When classifying background enhancement at early dynamic phase, the accuracy of tumor extent assessment by MRI with moderate/marked background enhancement was 60%, which was lower than the 78% accuracy with minimal/mild background enhancement, but not significantly so (p?=?0.153). When classifying background enhancement at late dynamic phase, the accuracy with moderate/marked background enhancement was 61%, which was significantly lower than the 83% accuracy with minimal/mild background enhancement (p?=?0.034). There was no tumor-size-related bias between the groups (p?=?0.089).

Conclusion

The degree of background enhancement on breast MRI affects the accuracy of breast cancer extent assessment, especially at late dynamic phase.  相似文献   
62.
BACKGROUND: Percutaneous imaging-guided core needle biopsy (CNB) is being used increasingly as an alternative to surgical biopsy for the diagnosis of breast lesions that are suspicious or highly suggestive of malignancy. The purpose of this study was to evaluate ultrasonographically (US) guided 18-gauge automated CNB with post-fire needle position verification (PNPV) in the assessment of US visible breast lesions. METHODS: Biopsy of 235 US visible breast lesions was performed using US-guided 18-gauge core needles (18-GCN). After firing the biopsy needle, an image was obtained in the orthogonal plane to confirm the precise post-fire position of the needle track before removing the needle. Needle core diagnoses were compared with surgical diagnoses in 235 lesions subsequently surgically excised. RESULTS: The median size of the lesions was 14 mm (range, 5-60 mm). Agreement between needle core and surgical diagnoses in the 235 lesions was 92% including 192 cancers, 28 benign lesions, and 3 high-risk lesions. In the remaining 12 discordant lesions, 4 were high-risk lesions and 8 were benign lesions. In all 8 benign lesions, imaging-histological discordance was present. The sensitivity of US guided 18-GCNB for breast cancer was 96% (199 of 207). In 71% (167/235) of the cases only one core with PNPV was made. No complications occurred. CONCLUSION: US-guided 18-GCNB for sonographically-demonstrated discrete mass lesions with PNPV is an accurate core needle biopsy technique of breast cancer. During the course of tissue sampling, evaluating the post-fire needle tip position by obtaining an orthogonal view with ultrasonographic guidance is the key to predicting the yield regardless of the size of the needle or the number of core samples.  相似文献   
63.

Purpose

Our aim was to evaluate the hepatocyte transporters in focal nodular hyperplasia (FNH) and FNH-like lesions and to correlate the grade of its expression with signal intensity on the hepatobiliary phase (HB phase) of gadoxetic-acid-enhanced magnetic resonance imaging (EOB-MRI).

Materials and methods

Thirteen histopathological confirmed cases including eight with EOB-MRI were studied. Immunohistochemical staining for transporter was performed and its grade semiquantitatively analyzed.

Results

Histopathologically, ten cases showed almost equal organic anion transporter polypeptide (OATP) 8 expression relative to the surrounding liver; the remaining three showed stronger OATP8 expression. In eight cases with EOB-MRI, two demonstrated more hyperintensity on the HB phase, and their OATP8 expression was stronger compared with the surrounding liver. The remaining six cases showed isointensity on the HB phase and revealed almost equal OATP8 expression. The expression of export transporter multi-drug-resistant proteins (MRP) 1 and 2 were almost equal relative to the surrounding liver in most cases (11/12, 92?%; 11/12, 92?%, respectively), whereas MRP3 focally overexpressed in 75?% (9/12) of cases.

Conclusion

FNH and FNH-like nodules revealed equal or stronger OATP8 expression than background liver. OATP8 expression showed significant correlation with signal intensity on the HB phase.  相似文献   
64.
General Thoracic and Cardiovascular Surgery - 14 living flaps in 8 children were used to repair for the congenital heart disease, because artificial material and xeno grafts were shrunk in growing...  相似文献   
65.
66.
Purpose To prospectively evaluate whether dynamic contrast-enhanced magnetic resonance (MR) imaging findings can help predict the presence of malignancy when screening detected microcalcification lesions, and its contribution to patient management of stereotactic vacuum-assisted breast biopsy (SVAB). Materials and methods Dynamic contrast-enhanced breast MR imaging was performed when screening 100 detected microcalcification lesions not visualized by ultrasonography with 11-gauge SVAB. Definitive surgery was performed on all patients with the biopsy resulting in the diagnosis of breast cancer or atypical ductal hyperplasia (ADH). Positive predictive values (PPVs) and negative predictive values (NPVs) were calculated on the basis of a BI-RADS (Breast Imaging Reporting and Data System) category and the absence or presence of contrast uptake in the area of microcalcification. Results The BI-RADS mammography category correlated with the diagnosis of breast cancer (ADH excluded): category 3 = 7% (4/55); category 4 = 48% (13/27); category 5 = 94% (17/18). After dynamic contrast-enhanced MR imaging, three of four malignancies with BI-RADS mammography category 3 were diagnosed as true positive. Therefore, the PPV of BI-RADS mammography category 3 with MR imaging was 1.8% (1/55). The PPV of contrast uptake of MR imaging was 86% (32/37), significantly higher than the 67% (30/45) PPV of BI-RADS mammography 4 and 5 (P = 0.033). The NPV of BI-RADS mammography 3 was 93% (51/55) versus 97% (61/63) NPV of MR imaging (P = 0.167). Conclusion In the evaluation of screening detected microcalcification lesions, dynamic contrast-enhanced breast MR imaging provides additional information with high PPV and NPV, and may therefore offer an alternative to SVAB for women who do not want to undergo SVAB with equivocal findings following full diagnostic mammographic assessment, but breast MR imaging with imperfect PPV and NPV cannot replace SVAB. Clinical relevance Dynamic contrast-enhanced breast MR imaging can demonstrate malignant microcalcifications detected by screening mammography and can be recommended in the evaluation of equivocal microcalcifications prior to SVAB.  相似文献   
67.
68.
A 21-year-old woman with a 5-cm secretory carcinoma of the breast was successfully treated by wide segmental excision, including removal of a portion of the nipple. At presentation, she had a 5-year history of predominantly yellow and occasionally bloody discharge from the nipple. The tumour had classical histological features of secretory carcinoma with surrounding hyaline fibrous tissue predominating, a feature previously associated with a good prognosis. Identification by frozen section of extension near the nipple led to intraoperative excision of a nipple segment. She is healthy with a satisfactory cosmetic result 14 years after excision and has breast fed two children from the affected breast.  相似文献   
69.
The genus Aloe in the family Liliaceae is a group of plants including Aloe vera (Aloe barbadensis MILLER) and Aloe arborescens (Aloe arborescens MILLER var. natalensis BERGER) that are empirically known to have various medical efficacies. In the present study, we evaluated the anti-hyperglycemic effect of Aloe vera gel and isolated a number of compounds from the gel. On the basis of spectroscopic data, these compounds were identified as lophenol, 24-methyl-lophenol, 24-ethyl-lophenol, cycloartanol, and 24-methylene-cycloartanol. These five phytosterols were evaluated for their anti-hyperglycemic effects in type 2 diabetic BKS.Cg-m(+/+)Lepr(db/J) (db/db) mice. In comparison with the hemoglobin A1c (HbA1c) levels of vehicle-treated mice, statistically significant decreases of 15 to 18% in HbA1c levels were observed in mice treated with 1 mug of the five phytosterols. Considering the ability to reduce blood glucose in vivo, there were no differences between the five phytosterols. Administration of beta-sitosterol did not reduce the blood glucose levels in db/db mice. After administration of the five phytosterols for 28 d, fasting blood glucose levels decreased to approximately 64%, 28%, 47%, 51%, and 55% of control levels, respectively. Severe diabetic mice treated with phytosterols derived from Aloe vera gel did not suffer weight reduction due to glucose loss in the urine. These findings suggest that Aloe vera gel and phytosterols derived from Aloe vera gel have a long-term blood glucose level control effect and would be useful for the treatment of type 2 diabetes mellitus.  相似文献   
70.
Intracytoplasmic and extracytoplasmic features of secretion, similar to lactational changes, occasionally are seen in the nonparous human breast, usually are lobulocentric, and often have aberrant cytologic and nuclear changes. In these "hypersecretory hyperplasias" (HHs; 38 women) there is bubbly cytoplasm with irregular apical cytoplasmic and/or nuclear protrusions. In a review of 138 HH cases the following additional associated changes were found: nuclear atypia (HHA, 22 women), atypical ductal hyperplasia (ADH-HH, 24 women), and ductal carcinoma in situ (DCIS-HH, 54 women). A diagnosis of DCIS-HH requires involvement of true duct(s) and of several contiguous lobular units, emphasizing the importance of extent and overall size and similar cytology and histologic arrangement of intercellular spaces indicating a homogeneous cell population. Cases of HH regularly are characterized as having adjacent and nearby lobular units with quite diverse cytologic patterns. The major impact of this study is to recognize that HHA may be regarded as having uncertain significance when found alone in the usual presentation in a single unit, but that formally defined ADH and/or DCIS may be locally present.  相似文献   
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