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Tumor Border (tumor + border)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Amplification of the epidermal growth factor receptor gene in glioblastoma: An analysis of the relationship between genotype and phenotype by CISH method

NEUROPATHOLOGY, Issue 2 2008
Tomomi Miyanaga
We examined epidermal growth factor receptor (EGFR) overexpression and EGFR gene amplification using immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH) in 109 glioblastomas, including 98 primary glioblastomas and 11 secondary glioblastomas. EGFR overexpression and EGFR gene amplification were found in 33% and 24% of glioblastoma, respectively, and all of those cases were primary glioblastoma. Large ischemic necrosis was significantly more frequent in primary glioblastomas than in secondary glioblastomas (54% vs. 18%), but pseudopalisading necrosis was not (65% vs. 54%). EGFR gene amplification was detected significantly more frequently in cases with both types of necrosis. Although glioblastomas with EGFR gene amplification invariably exhibited EGFR overexpression at the level of the whole tumor, tumor cells with EGFR gene amplification did not always show EGFR overexpression at the level of individual tumor cells. Cases of "strong" EGFR overexpression on IHC could be regarded as having EGFR gene amplification, and cases without EGFR overexpression could not. Cases of "weak" EGFR overexpression should be tested with CISH to confirm the presence of EGFR gene amplification. We found that 54% of glioblastomas with EGFR gene amplification were composed of areas with and without EGFR gene amplification; however, there were no obvious differences in morphology between tumor cells with and without EGFR gene amplification. Although small cell architecture might be associated with EGFR gene amplification at the level of the whole tumor, it did not always suggest amplification of the EGFR gene at the level of individual tumor cells. In one case, it seemed to suggest that a clone with EGFR gene amplification may arise in pre-existing tumor tissue and extend into the surrounding area. In cases of overall EGFR amplification, CISH would be a useful tool to decide the tumor border in areas infiltrated by tumor cells. [source]

Longitudinal diffusion tensor imaging in a rat brain glioma model

NMR IN BIOMEDICINE, Issue 8 2008
Silvia Lope-Piedrafita
Abstract In order to investigate the properties of water motion within and around brain tumors as a function of tumor growth, longitudinal diffusion tensor imaging (DTI) was carried out in a rat brain glioma (C6) model. As tumors grew in size, significant anisotropy of water diffusion was seen both within and around the tumor. The tissue water surrounding the tumor exhibited high planar anisotropy, as opposed to the linear anisotropy normally seen in white matter, indicating that cells were experiencing stress in a direction normal to the tumor border. When tumors were sufficiently large, significant anisotropy was also seen within the tumor because of longer-range organization of cancer cells within the tumor borders. These findings have important implications for diffusion-weighted MRI experiments examining tumor growth and response to therapy. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Presence of a Micropapillary Pattern in Mucinous Carcinomas of the Breast and its Impact on the Clinical Behavior

THE BREAST JOURNAL, Issue 5 2008
Tanuja Shet MD
Abstract:, Infiltrating micropapillary carcinomas (IMPC) of breast are highly angioinvasive tumors with poor prognosis. This study is based on the observation that a similar micropapillary pattern is also observed in mucinous carcinomas of breast. About 102 mucinous carcinomas were evaluated for the presence and impact of this micropapillary pattern on the clinical behavior. Of these, 68 were mucinous carcinomas with a micropapillary pattern (MUMPC), 20 had MUMPC mixed with an infiltrating duct carcinoma component, two were solid variants of papillary carcinoma with mucin (SVPCMU), five had collision of the MUMPC and SVPCMU patterns and seven were mucinous carcinomas with signet ring cells (MUS). The factors negatively affecting overall survival (OAS) and disease-free survival (DFS) included the histological type of mucinous carcinoma, nodal metastases, an irregular tumor border, <50% mucin and an IMPC type of local recurrence or metastases. In the multivariate analysis, the histologic type of mucinous carcinoma and an irregular tumor border were most significant for OAS and DFS. Thus, 86% of mucinous carcinomas in this study were mucinous variants of the angioinvasive infiltrating micropapillary carcinomas. These tumors can produce IMPC type of metastases and thus should be treated aggressively. [source]

Use of High-Frequency, High-Resolution Ultrasound Before Mohs Surgery

DERMATOLOGIC SURGERY, Issue 6 2010
ELLEN S. MARMUR MD
BACKGROUND Although ultrasound imaging is employed ubiquitously today, its use to examine and assess the skin is a relatively new technology. We explored the clinical application and use of high-frequency, high-resolution ultrasound in Mohs micrographic surgery. OBJECTIVE To evaluate the ability of ultrasound to accurately determine lesion length and width of tumor borders in order to reduce the number of surgical stages. METHODS AND MATERIALS This was an institutional review board,approved single-center study of 26 Mohs surgery patients. Ultrasound images were taken to record lesion dimensions, and then the investigator documented clinical estimation of the first stage. Extirpation of the tumor and histological analysis were performed thereafter. RESULTS The results of 20 patients were included in the analysis. A paired-samples t -test revealed no significant difference between clinical and ultrasound widths (t=,1.324, p=.20). Similarly, there was no significant difference between the lengths found from clinical assessment and ultrasound (t=,1.093, p=.29). For different tumor types, there was no significant difference between clinical and ultrasound widths or lengths for basal cell carcinoma (t=,1.307, p=.23; t=,1.389, p=.20) or squamous cell cancer (t=,0.342, p=.73; t=0.427, p=.68). CONCLUSION There is a diagnostic role for high-resolution ultrasound in Mohs surgery regarding the delineation of surgical margins, but its limitations preclude its practical adoption at this time. The ultrasound equipment was loaned to the investigators. Funding for the study was provided by Longport, Inc. [source]

Assessment of Optical Coherence Tomography Imaging in the Diagnosis of Non-Melanoma Skin Cancer and Benign Lesions Versus Normal Skin: Observer-Blinded Evaluation by Dermatologists and Pathologists

DERMATOLOGIC SURGERY, Issue 6 2009
METTE MOGENSEN MD
BACKGROUND Optical coherence tomography (OCT) is an optical imaging technique that may be useful in diagnosis of non-melanoma skin cancer (NMSC). OBJECTIVES To describe OCT features in NMSC such as actinic keratosis (AK) and basal cell carcinoma (BCC) and in benign lesions and to assess the diagnostic accuracy of OCT in differentiating NMSC from benign lesions and normal skin. METHODS AND MATERIALS OCT and polarization-sensitive (PS) OCT from 104 patients were studied. Observer-blinded evaluation of OCT images from 64 BCCs, 1 baso-squamous carcinoma, 39 AKs, two malignant melanomas, nine benign lesions, and 105 OCT images from perilesional skin was performed; 50 OCT images of NMSC and 50 PS-OCT images of normal skin were evaluated twice. RESULTS Sensitivity was 79% to 94% and specificity 85% to 96% in differentiating normal skin from lesions. Important features were absence of well-defined layering in OCT and PS-OCT images and dark lobules in BCC. Discrimination of AK from BCC had an error rate of 50% to 52%. CONCLUSION OCT features in NMSC are identified, but AK and BCC cannot be differentiated. OCT diagnosis is less accurate than clinical diagnosis, but high accuracy in distinguishing lesions from normal skin, crucial for delineating tumor borders, was obtained. [source]