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61.
In breast conservation therapy, the margin status of the specimen predicts local recurrence and determines the need for reexcision. Many surgeons now take, at the time of lumpectomy, multiple separate "cavity margins" (CM) (the entire wall of the residual cavity) as final margins that supersede the oriented lumpectomy margins (LMs). We studied the efficacy of this method in 126 patients (23 with ductal carcinoma in situ [DCIS] only and 103 with invasive carcinoma with or without DCIS) who had an oriented lumpectomy specimen and also had four to six additional CMs. The tumors were evaluated for the following: size, grade, LM status (distance of tumor from margin and, if involved, extent of involvement), vascular invasion, lymph node status, and presence or absence of extensive intraductal component. The additional CM specimens were evaluated for residual carcinoma (if any) and its distance from the inked true margins, and the results were correlated with the corresponding LMs. Only approximately 50% of patients (52 of 103) with histologically positive LMs (defined as carcinoma within 2 mm of the inked surface) had residual carcinoma in their CMs. Additional CM sampling rendered the overall final margin status histologically negative in 61 of 103 (59%) cases with histologically positive LMs, therefore significantly reducing the need for reexcision. Younger patient age, higher number of positive LMs, high tumor grade, and the presence of extensive intraductal component were predictive of residual carcinoma in CM specimens, whereas the distance of carcinoma from the inked surface and the extent of tumor involvement of histologically positive LMs were not. Because CM specimens taken from patients with histologically positive LMs usually lack tumor, we suspect that many positive LMs are likely false positives. Possible factors accounting for false-positive LMs include seepage of ink into crevices of the specimen promoted by excessive inking, tumor friability promoting displacement of tumor into ink, manipulation of specimens for radiographs, and retraction artifact.  相似文献   
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Environmental pollution of aquatic ecosystems leads to an interference in several fundamental biochemical and physiological functions. In this study the interference of Cd and Pb pollutions on the physiological growth and subsequently on the age determination was investigated. The hermit crab, Coenobita scaevola (C.s) was selected as a bioaccumulator in this study. The direct and indirect age determination methods were carried out using annual band counts and carapace length, respectively. The results showed that, there was very low correlation (R2?<?0.5) between direct and indirect age determination. Wavelet Neural Network (WNN) was applied to take into account the environmental effects such as the accumulation of Cd and Pb elements in the C.s’ tissues. It was observed that WNN successfully enhanced the growth rate model and estimated the C.s’ age (R2?>?0.95). In addition, it was concluded that the environmental pollution had interaction with the growth physiology such as weight and length.  相似文献   
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A 54-year-old woman was hospitalized for flank pain and acute renal failure when imaging studies revealed a 5.2 cm mass in the left kidney. She was referred for fine needle aspiration of the lesion, which showed an epithelial tumor with round to oval nuclei associated with strands of metachromatic stromal tissue. Cytopathologic diagnosis was consistent with renal cell carcinoma. Subsequent nephrectomy was performed and the surgical pathology specimen showed a mucinous tubular and spindle cell carcinoma of the kidney. The patient has done well post-operatively with 10 months of benign follow-up.  相似文献   
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The objective of this study was to determine and compare cystatin C changes before and after radiotherapy in patients with stomach cancer who were candidate for radiotherapy. This study was conducted as a prospective cohort one. Eighteen patients with definite diagnosis of stomach cancer under treatment by radiotherapy who presented to Radiotherapy-Oncology Center of Imam Hossein Hospital, Tehran-Iran, and the treatment in all cases was simultaneous chemoradiation with Xeloda were included. In all patients before radiotherapy and after radiotherapy serum creatinine (Cr) and cystatin C were measured simultaneously. Mean cystatin level before treatment (1.2 ± 0.4) was significantly lower than that of post-treatment (1.6 ± 0.36), (P=0.001). Serum Cr level before treatment was 1.15 ± 0.33 and after radiotherapy was 1.08 ± 0.24 and did not show significant difference. Glomerular filtration rate (GFR) of the patients before radiotherapy was -46.8 ± 21.0 and after radiotherapy was 43.8 ± 15.8 that did not have significant difference (P=0.146) and also blood urea nitrogen (BUN) before radiotherapy was 20.72 ± 3.7 and 20 ± 6.38 after radiotherapy that did not have significant difference (P=0.6). Comparison of the cystatin C difference with total radiation dose of the kidneys that are put in three dose groups in radiotherapy field had association that in dose of less that 18 gray (Gy) the cystatin C change showed significant and positive association (P=0.027; r=0.52) and about 18-24 Gy the cystatin C difference showed significant and negative association (P=0.023, r=-0.53). It seems that for evaluating the renal function, serum cystatin C measurement is preferable than serum Cr. level.  相似文献   
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A subset of renal cell carcinomas (RCCs) is characterized by t(6;11)(p21;q12), which results in fusion of the untranslated Alpha (MALAT1) gene to the TFEB gene. Only 21 genetically confirmed cases of t(6;11) RCCs have been reported. This neoplasm typically demonstrates a distinctive biphasic morphology, comprising larger epithelioid cells and smaller cells clustered around basement membrane material; however, the full spectrum of its morphologic appearances is not known. The t(6;11) RCCs differ from most conventional RCCs in that they consistently express melanocytic immunohistochemical (IHC) markers such as HMB45 and Melan A and the cysteine protease cathepsin K but are often negative for epithelial markers such as cytokeratins. TFEB IHC has been proven to be useful to confirm the diagnosis of t(6;11) RCCs in archival material, because native TFEB is upregulated through promoter substitution by the gene fusion. However, IHC is highly fixation dependent and has been proven to be particularly difficult for TFEB. A validated fluorescence in situ hybridization (FISH) assay for molecular confirmation of the t(6;11) RCC in archival formalin-fixed, paraffin-embedded material has not been previously reported. We report herein the development of a break-apart TFEB FISH assay for the diagnosis of t(6;11)(p21;q12) RCCs. We validated the assay on 4 genetically confirmed cases and 76 relevant expected negative control cases and used the assay to report 8 new cases that expand the clinicopathologic spectrum of t(6;11) RCCs. An additional previously reported TFEB IHC-positive case was confirmed by TFEB FISH in 46-year-old archival material. In conclusion, TFEB FISH is a robust, clinically validated assay that can confirm the diagnosis of t(6;11) RCC in archival material and should allow a more comprehensive clinicopathologic delineation of this recently recognized neoplastic entity.  相似文献   
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