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Michael S Watson

Publications and source records attributed to Michael S Watson.

4 recordsLinked to original sources
PubMed2002

Pretreatment cytogenetic abnormalities are predictive of induction success, cumulative incidence of relapse, and overall survival in adult patients with de novo acute myeloid leukemia: results from Cancer and Leukemia Group B (CALGB 8461).

We analyzed prospectively 1213 adults with de novo acute myeloid leukemia (AML) to ascertain the prognostic impact of cytogenetic abnormalities on complete remission (CR) rate, 5-year cumulative incidence of relapse (CIR), and 5-year overall survival (OS). All patients received similar induction therapy. Median follow-up for surviving patients was 8.3 years. Nonprioritized cytogenetics distinguished t(8;21) and inv(16)/t(16;16) as conferring a significantly better prognosis than normal karyotype. Prognostic impact of many abnormalities could not be determined independently because of their association with complex karyotype. Neither complex karyotype nor secondary aberrations affected outcome of patients with t(8;21), inv(16)/t(16;16), or t(9;11). Among other patients, those with complex karyotypes had significantly worse outcomes than cytogenetically normal patients. Based on outcome for specific cytogenetic abnormalities and karyotype complexity, patients were divided into 3 risk groups: favorable (CR 88%, CIR 54%, OS 55%), intermediate (CR 67%, CIR 67%, OS 24%), and adverse (CR 32%, CIR 92%, OS 5%). Multivariate analyses confirmed the major contribution of cytogenetics to the probability of attaining CR, CIR, and OS. For the adverse-risk group, the probability of achieving CR was 4.0 and 11.9 times lower, the probability of relapse 3.0 and 4.4 times higher, and the risk of death 2.1 and 4.3 times higher than those for the intermediate and favorable groups, respectively. We conclude that although the prognostic impact of many recurring abnormalities has not been ascertained independently of complex karyotype, cytogenetics is among the most useful factors predicting attainment of CR, CIR, and long-term survival in adult AML.

Acute Disease↗
PubMed2002

NIST physical standards for DNA-based medical testing.

As DNA and RNA become major targets for clinical laboratory analysis, benchmark reagents will play an increasingly important role in standardization. Reliable national and international nucleic acid standards promote automation and third-party reimbursement for clinical testing. Furthermore, nucleic acid standards provide materials for quality assurance and quality control (QA/QC), and proficiency testing. Standard methods and training initially evolved from consensus guidelines endorsed by professional societies and governmental agencies. The National Institute of Standards and Technology (NIST), a nonregulatory agency of the U.S. Department of Commerce, develops and certifies physical and chemical standards in support of national commerce, manufacturing, and science. In its role supporting U.S. science and industry, the NIST responds to specific standards needs, most recently for medically and biologically important analytes. Broad-based consensus developed through interdisciplinary NIST workshops initiated development of NIST-certified DNA standards. Such materials serve the diagnostic community and help manufacturers benchmark a variety of DNA diagnostic testing platforms. Here we summarize the NIST experience and programs for development of national standards for DNA-based medical diagnostic testing.

Clinical Laboratory Techniques↗
PubMedDate not supplied

Standards and guidelines for CFTR mutation testing.

One mission of the ACMG Laboratory Quality Assurance (QA) Committee is to develop standards and guidelines for clinical genetics laboratories, including cytogenetics, biochemical, and molecular genetics specialties. This document was developed under the auspices of the Molecular Subcommittee of the Laboratory QA Committee by the Cystic Fibrosis (CF) Working Group. It was placed on the "fast track" to address the preanalytical, analytical, and postanalytical quality assurance practices of laboratories currently providing testing for CF. Due to the anticipated impact of the ACMG recommendation statement endorsing carrier testing of reproductive couples, it was viewed that CF testing would increase in volume and that the number of laboratories offering CF testing would also likely increase. Therefore, this document was drafted with the premise of providing useful information gained by experienced laboratory directors who have provided such testing for many years. In many instances, "tips" are given. However, these guidelines are not to be interpreted as restrictive or the only approach but to provide a helpful guide. Certainly, appropriately trained and credentialed laboratory directors have flexibility to utilize various testing platforms and design testing strategies with considerable latitude. We felt that it was essential to include technique-specific guidelines of several current technologies commonly used in laboratories providing CF testing, since three of the four technologies discussed are available commercially and are widely utilized. We take the view that these technologies will change, and thus this document will change with future review.

Cystic Fibrosis↗