title: Fully automated dual-color dual-hapten silver in situ hybridization staining for MYC amplification: a diagnostic tool for discriminating secondary angiosarcoma.
abstract: BACKGROUND
  MYC amplification occurs in post-radiation and chronic lymphedema-associated secondary angiosarcoma and some primary angiosarcomas. In this study, we tested the ability of automated dual-color dual-hapten in situ hybridization (DISH) staining to discriminate secondary angiosarcoma from radiation-associated atypical vascular lesions (AVL), and to correlate with fluorescence in situ hybridization (FISH) for MYC amplification.
  
  
  METHODS
  Cases of secondary angiosarcoma, including 11 biopsies and 3 excisions from 11 patients, and 5 AVL biopsies from 5 patients, were examined by FISH and DISH. DISH staining was performed using the Dual Color Open Probe software on a Ventana Benchmark XT automated slide stainer. Metallic black silver (MYC) and reference CHR8 red signals were qualitatively and semi-quantitatively enumerated for tumor nuclei. Small and large clusters of silver signals were recorded as 6 or 12 signals, respectively. MYC amplification was defined as MYC/CHR8 ratio >2.0.
  
  
  RESULTS
  Where tissue was available for both DISH and FISH, all secondary angiosarcoma cases showed MYC amplification (11/11 = 100%) by both DISH and FISH. All AVL were negative for MYC amplification by both techniques (0/5 = 0%).
  
  
  CONCLUSIONS
  In the current cohort, use of DISH identified all MYC amplified cases, and distinguished secondary angiosarcoma from AVL. DISH staining may be useful in distinguishing secondary angiosarcoma from AVL in challenging cases.
authors: Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH, USA.
authors: Jennifer S
authors: JS
authors: Ko
authors: Steven D
authors: SD
authors: Billings
authors: Christopher P
authors: CP
authors: Lanigan
authors: Darya
authors: D
authors: Buehler
authors: Anthony P
authors: AP
authors: Fernandez
authors: Raymond R
authors: RR
authors: Tubbs
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005784:Gene Amplification; D006394:Hemangiosarcoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006801:Humans; D017403:In Situ Hybridization / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism; D012189:Retrospective Studies; D012834:Silver / Q000737:chemistry*; D012878:Skin Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology
chemical_list: C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D012834:Silver
keywords: MYC; atypical vascular lesions; in situ hybridization; secondary angiosarcoma; soft tissue tumors