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991.
The consistency of a request for liver MRI and MR-cholangiopancreatography in a patient with an occasional US-finding of mural thickening of gallbladder fundus > or = 3 mm in size was assessed. The differential US diagnosis in case of focal mural thickening was analyzed in combination with the other findings to justify the radiologicoclinical reliability of the request. Overall, these findings suggested the diagnostic hypothesis of adenomyomatosis, then confirmed by a second level in-depth examination, namely liver MRI and MR-cholangiopancreatography.  相似文献   
992.
BACKGROUND AND OBJECTIVES: We studied the impact of metatasectomy on disease outcome in 29 advanced nonmedullary thyroid carcinoma (ThyrCa) patients who were operated on between 1969 and 2001 at NIH to further define its role in the management of this malignancy. METHODS: Data were extracted by retrospective chart review. A Kaplan-Meyer survival curve was constructed, and comparative stratification for various parameters was performed. RESULTS: During 47 surgeries, the following lesions were resected from mid-mediastinum/hila, 17; lung parenchyma, 12; skeleton, 14; kidneys, 2; and brain, 2. All patients received multiple radioiodine (RAI) treatments. External-beam radiotherapy, chemotherapy and other palliative measures were used in selected patients. Six patients (21%) died within 74.7 +/- 54.7 months after the first distant metastasectomy. The outcome of the remaining patients was as follows: complete remission, 3; partial remission, 10; and 10: progressive disease, 10, with a follow-up of 175 patient-years. Metastasectomy led to a decrease of 38% in thyroglobulin levels in 23 patients. Cumulative survival rates were 78.5 +/- 8.4% at 5 years and 50.2 +/- 12.5% at 10 years (mean +/-SEM) after initial distant metastasectomy. CONCLUSIONS: Our data show that extensive targeted metastasectomy in the setting of a tertiary center can be beneficial to patients with disseminated ThyrCa with persistent or recurrent distant disease, when used in conjunction with nonsurgical treatment modalities.  相似文献   
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995.
Epidemiologic studies have suggested that dietary folate intake is inversely related to breast cancer risk. However, epidemiologic evidence has not been consistent nor has it provided unequivocal support for this purported inverse relationship. This study investigated the effect of dietary folate on N-methyl-N-nitrosourea (MNU)-induced mammary tumorigenesis in rats. Weanling, female Sprague-Dawley rats were fed diets containing either 0 (deficient; n = 22), 2 (basal dietary requirement, control; n = 20) or 8 mg (supplemented; n = 20) folate/kg diet for 30 weeks. At 50 days of age, rats received an i.p. injection of MNU (50 mg/kg body wt). At necropsy, all macroscopic mammary tumors were identified and examined microscopically. The effect of dietary folate on genomic DNA methylation in mammary tumorigenesis was determined by the in vitro methyl acceptance assay. The incidence of mammary adenoma and adenocarcinoma in the folate-deficient group was lower than that of the control and folate-supplemented groups (55 versus 90 and 75%, respectively, P = 0.043). Kaplan-Meier analyses also demonstrated a similar trend in the rates of appearance of either adenoma or adenocarcinoma (P = 0.06). In contrast, folate supplementation did not significantly modulate mammary tumorigenesis compared with the control group. Although mammary tumors were significantly hypomethylated compared with non-neoplastic mammary tissues in each dietary group (P < 0.03), folate status did not significantly affect the extent of DNA methylation. The data suggest that dietary folate deficiency of a moderate degree suppresses, whereas folate supplementation at four times the basal dietary requirement does not significantly modulate, mammary tumorigenesis in this model. The role of folate in mammary tumorigenesis needs to be clarified for safe and effective prevention of breast cancer.  相似文献   
996.
BACKGROUND: Multiple treatment guidelines and practice standards have been developed regarding the management of patients with breast carcinoma. Few evaluations of the penetration and utility of these practice standards have been performed. In 1992, the American College of Surgeons (ACOS), the American College of Radiology, the College of American Pathologists, and the Society of Surgical Oncology collaborated in establishing standards for breast-conservation treatment (BCT). The authors sought to determine whether practice patterns for patients with breast carcinoma who underwent BCT were consistent with these standards 2 years after their dissemination and to establish whether compliance varied by the same patient and hospital variables that predicted for the amount of BCT performed. METHODS: A study specific questionnaire was circulated to cancer registrars through the Commission on Cancer of the ACOS asking them to submit reports on patients with Stage I and II breast carcinoma who were diagnosed in 1994. Eight hundred forty-two predominantly community hospitals throughout the United States responded, yielding a total of 16,643 analyzable patients. The frequency of compliance to the 1992 published practice standards for 7097 patients who received BCT was determined. The variation in compliance rates by patient age, race, and insurance status and the treating hospital's geographic locations and cancer programs were evaluated. RESULTS: Of the 22 standards that were evaluated in the areas of preoperative mammography (2 standards), labeling of the surgical specimen (3 standards), pathology report content (10 standards), radiation after lumpectomy (6 standards), and systemic therapy for patients with positive lymph nodes (1 standard), treatment adherence was > or = 80% for 16 standards (73%). Poor compliance was demonstrated for six standards: the documentation of an abnormality's size in the mammogram report, labeling the lumpectomy specimen with the affected quadrant of the breast, spatial orientation of the lumpectomy specimen and inclusion of lymphatic/vascular invasion, ductal carcinoma in situ, and macroscopic margin assessment in the pathology report. Variation in compliance to a standard occurred frequently across the type of hospital cancer program and geographic region (77% for both), and variation occurred less across the patient variables of age (32%), race (41%), and payer (23%). There was not a pattern of more frequent compliance among variables associated with more BCT use. CONCLUSIONS: Large-scale evaluation of the penetration of treatment standards is feasible. For patients who underwent lumpectomy, practice appeared to be consistent (> or = 80% compliance), with 73% of 22 treatment standards evaluated. The standards with poor compliance represent areas for targeted physician education and reevaluation. Significant differences in adherence to a standard were seen frequently based on a hospital's geographic location and type of cancer program. This emphasizes the importance of adequate dissemination of treatment standards to ensure penetration into medical practices of all types.  相似文献   
997.
BACKGROUND: The objective of this study was to clarify the prognostic and predictive value of immunoreactivity for the cyclin-dependent kinase inhibitor p27(Kip1) in patients with early-stage breast carcinoma and to investigate its relation with clinicopathologic features and other markers. METHODS: Immunoreactivity for p27 protein was analyzed on tumor slides from 461 patients who were enrolled in the International Breast Cancer Study Group (IBCSG) Trial V (median follow-up, 13 years), including 198 patients with lymph node negative disease and 263 patients with lymph node positive disease. Tumors with < 50% immunoreactive neoplastic cells were considered low expressors. Immunoreactivity for p27 was correlated with several clinicopathologic characteristics. Disease free survival (DFS) and overall survival were analyzed according to p27 immunoreactivity and treatment group. RESULTS: In the lymph node negative population, decreased p27 immunoreactivity was associated with higher tumor grade (P = 0.001) and HER-2/neu overexpression (P = 0.04). In the lymph node positive population, low p27 expression was associated with higher tumor grade (P = 0.01), low expression of thymidylate synthase (P = 0.001), and higher Ki-67 expression (P = 0.007). DFS was not significantly different according to p27 status in either lymph node negative patients (10-year DFS: low p27 expression, 53% +/- 5%; high p27 expression, 55% +/- 5%) or in lymph node positive patients (10 year DFS: low p27 expression, 33% +/- 4%; high p27 expression, 32% +/- 4%). However, in the lymph node negative population, the benefit of one course of perioperative chemotherapy with cyclophosphamide, methotrexate, and 5-fluorouracil was confined exclusively to patients with tumors that showed reduced p27 immunoreactivity (P = 0.03; test for interaction). CONCLUSIONS: This analysis indicates that p27 immunoreactivity has little if any prognostic value in patients with early-stage breast carcinoma. However, these findings suggest that, in patients with breast carcinoma who have negative lymph node status, reduced p27 immunoreactivity is associated with HER-2/neu overexpression and may be predictive of a benefit from the early administration of adjuvant chemotherapy.  相似文献   
998.
999.
OBJECTIVE: Elevated androgens in women are associated with type 2 diabetes and are dependent on the conversion to estrogens by aromatase cytochrome P450. Polymorphisms of a tetranucleotide repeat [TTTA](n) in the fourth intron of the CYP19 gene are associated with endocrine-dependent diseases and were examined in relation to hormone levels and disease risk factors in premenopausal women. RESEARCH METHODS AND PROCEDURES: A population sample of women born in 1956 (n = 270) were genotyped for this polymorphism and the results set in relation to steroid hormones, including saliva cortisol, anthropometric variables, estimates of insulin, glucose and lipid metabolism, and blood pressure. RESULTS: Seven tetranucleotide repeat [TTTA](n) alleles were detected with allelic sizes of 168 to 195 bp, with a TCT deletion/insertion (168/171 bp) upstream of this microsatellite. Smoking was associated with elevated androgens (p = 0.005 to 0.019). Using the median (average stretch, 177.5 bp) as a dividing line, nonsmoking women with the shorter microsatellite had higher free testosterone (p = 0.018) and lower sex hormone binding globulin (p = 0.033). These differences were pronounced with the 168-bp allele. Such women were also characterized by a less-substantial decrease of morning cortisols ("unwinding"; p = 0.035) and central obesity (abdominal sagittal diameter, p = 0.049) and had waist/hip circumference ratios of borderline significance (p = 0.064). DISCUSSION: The results indicate that, in premenopausal women, a short microsatellite in the fourth intron of the CYP19 gene, caused by a TCT deletion upstream the [TTTA](n) tract, is associated with elevated androgens, perturbed regulation of the hypothalamic-pituitary-adrenal axis, and abdominal obesity.  相似文献   
1000.
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