Section E9 of the American College of Medical Genetics technical standards and guidelines: Fluorescence in situ hybridization

Abstract

This updated Section E9 has been incorporated into and supersedes the previous Section E9 in Section E: Clinical Cytogenetics of the 2008 Edition (Revised 02/2007) American College of Medical Genetics Standards and Guidelines for Clinical Genetics Laboratories. This section deals specifically with the standards and guidelines applicable to fluorescence in situ hybridization analysis.

Diagnostic cytogenetic testing following positive noninvasive prenatal screening results: a clinical laboratory practice resource of the American College of Medical Genetics and Genomics (ACMG)

“…Any value below these cutoff values or thresholds would be considered negative. 33 CMAs may also be ordered as part of the follow-up testing, although detection of low-level mosaicism may be more challenging than by chromosome analysis and/or interphase FISH analysis 34 ( Table 1).…”

Population-based characterization of the genetic landscape of chronic lymphocytic leukemia patients referred for cytogenetic testing in British Columbia, Canada: the role of provincial laboratory standardization

“…Each laboratory processes approximately 100e200 CLL FISH specimens per year and follows the CCMG-endorsed ACMG standards and guidelines for FISH analyses (24). All laboratories were accredited through the national Diagnostic Accreditation Program for clinical laboratory services and participated in regular proficiency testing through surveys from the College of American Pathologists and/or the Canadian Quality Management ProgramdLaboratory Services (QMPLS).…”

“…Lab A used the commercially available CLL FISH Probe Kit (Abbott Laboratories, Abbott Park, IL), whereas Labs B and C used a commercially available CLL FISH panel (Cytocell, Cambridge, UK). Normal cutoff values were determined for each probe independently by each laboratory as per recommended guidelines and discretion of the laboratory directors (24) and are listed in Table 2. Labs A and C determined cutoffs by calculating the mean plus three standard deviations, whereas Lab B used the mean plus two standard deviations.…”

“…Between 2004 and 2011, FISH testing in BC was performed at one of three cytogenetic laboratories, prior to therapy, to guide treatment decisions. National guidelines to validate and interpret FISH assays in clinical practice are based on the American College of Medical Genetics (ACMG) guidelines, which are endorsed by the Canadian College of Medical Geneticists (CCMG) (24); however, certain aspects of FISH testing are left to the laboratory directors' discretion, including FISH probe design, scoring criteria, and statistical methods used to calculate normal cutoff values. The CLL Research Consortium (CRC) has highlighted the importance of FISH standardization within cooperative groups to ensure validity of clinical correlative studies that pool results from multiple laboratories (25).…”

The role of cytogenetics and molecular diagnostics in the diagnosis of soft-tissue tumors

“…Before reporting patient results, it is necessary for molecular laboratories to establish performance characteristics for normal reference ranges. 19,55 For example, reference ranges may differ between different types of preparations (eg cytologic touch preparation vs FFPE tissue section). Care should be taken in reporting results near the cutoff values.…”