48 research outputs found
The National Cancer Institute Thyroid fine needle aspiration state of the science conference: a summation
Breast tumor copy number aberration phenotypes and genomic instability
BACKGROUND: Genomic DNA copy number aberrations are frequent in solid tumors, although the underlying causes of chromosomal instability in tumors remain obscure. Genes likely to have genomic instability phenotypes when mutated (e.g. those involved in mitosis, replication, repair, and telomeres) are rarely mutated in chromosomally unstable sporadic tumors, even though such mutations are associated with some heritable cancer prone syndromes. METHODS: We applied array comparative genomic hybridization (CGH) to the analysis of breast tumors. The variation in the levels of genomic instability amongst tumors prompted us to investigate whether alterations in processes/genes involved in maintenance and/or manipulation of the genome were associated with particular types of genomic instability. RESULTS: We discriminated three breast tumor subtypes based on genomic DNA copy number alterations. The subtypes varied with respect to level of genomic instability. We find that shorter telomeres and altered telomere related gene expression are associated with amplification, implicating telomere attrition as a promoter of this type of aberration in breast cancer. On the other hand, the numbers of chromosomal alterations, particularly low level changes, are associated with altered expression of genes in other functional classes (mitosis, cell cycle, DNA replication and repair). Further, although loss of function instability phenotypes have been demonstrated for many of the genes in model systems, we observed enhanced expression of most genes in tumors, indicating that over expression, rather than deficiency underlies instability. CONCLUSION: Many of the genes associated with higher frequency of copy number aberrations are direct targets of E2F, supporting the hypothesis that deregulation of the Rb pathway is a major contributor to chromosomal instability in breast tumors. These observations are consistent with failure to find mutations in sporadic tumors in genes that have roles in maintenance or manipulation of the genome
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"…That which we call a Rose…": A critical analysis of rapid on-site evaluation.
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Fine-needle aspiration versus core needle biopsy: Reconsidering the evidence of superiority.
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Fine-needle aspiration versus core needle biopsy: Reconsidering the evidence of superiority.
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Fine-Needle Aspiration Biopsy of Liver Lesions Yields Higher Tumor Fraction for Molecular Studies: A Direct Comparison With Concurrent Core Needle Biopsy.
BackgroundThis retrospective study evaluated and compared the diagnostic accuracy and suitability of tissue specimens for advanced molecular diagnostic testing obtained via 2 different techniques for percutaneous biopsy of primary and metastatic liver tumors.Patients and methodsSamples from 137 patients with liver masses who underwent concurrent fine-needle aspiration biopsy with cell block (FNAB-CB) and core needle biopsy (CNB) at 2 hospitals were assessed for diagnostic accuracy, tumor fraction, and tumor cellularity. A subset of FNAB-CBs, that were deemed to have less or equal tumor cellularity compared with CNBs, had level sections performed and were reassessed for tumor cellularity.ResultsDiagnostic accuracy was 96% for FNAB and 93% for CNB (P=.267). In FNAB-CBs, tumor fraction was significantly higher than in CNB samples (67% vs 36%; P<.0001), whereas nontumor components were significantly lower (stromal component, 7% vs 29%; P<.0001; background benign hepatocytes, 25% vs 36%; P=.003). Additionally, in 44% of cases, FNAB-CB tumor cellularity was equal to or greater than that of the concurrent CNB.ConclusionsIn the current age of personalized medicine, a minimally invasive, safe approach to obtaining adequate tissue for myriad molecular testing is paramount. We have shown that FNAB sampling is diagnostically accurate and produces higher tumor fractions than CNB. Thus, FNAB should be strongly considered as an initial sampling modality, especially for patients in whom molecular tests will determine management
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Fine-Needle Aspiration Biopsy of Liver Lesions Yields Higher Tumor Fraction for Molecular Studies: A Direct Comparison With Concurrent Core Needle Biopsy.
BackgroundThis retrospective study evaluated and compared the diagnostic accuracy and suitability of tissue specimens for advanced molecular diagnostic testing obtained via 2 different techniques for percutaneous biopsy of primary and metastatic liver tumors.Patients and methodsSamples from 137 patients with liver masses who underwent concurrent fine-needle aspiration biopsy with cell block (FNAB-CB) and core needle biopsy (CNB) at 2 hospitals were assessed for diagnostic accuracy, tumor fraction, and tumor cellularity. A subset of FNAB-CBs, that were deemed to have less or equal tumor cellularity compared with CNBs, had level sections performed and were reassessed for tumor cellularity.ResultsDiagnostic accuracy was 96% for FNAB and 93% for CNB (P=.267). In FNAB-CBs, tumor fraction was significantly higher than in CNB samples (67% vs 36%; P<.0001), whereas nontumor components were significantly lower (stromal component, 7% vs 29%; P<.0001; background benign hepatocytes, 25% vs 36%; P=.003). Additionally, in 44% of cases, FNAB-CB tumor cellularity was equal to or greater than that of the concurrent CNB.ConclusionsIn the current age of personalized medicine, a minimally invasive, safe approach to obtaining adequate tissue for myriad molecular testing is paramount. We have shown that FNAB sampling is diagnostically accurate and produces higher tumor fractions than CNB. Thus, FNAB should be strongly considered as an initial sampling modality, especially for patients in whom molecular tests will determine management