title: Patients Tested at a Laboratory for Hereditary Cancer Syndromes Show an Overlap for Multiple Syndromes in Their Personal and Familial Cancer Histories.
abstract: OBJECTIVE
  Hereditary cancer testing guidelines are based on the premise that the common hereditary cancer syndromes have distinct, recognizable phenotypes. However, many syndromes present with overlapping cancers. The aim of this analysis was to identify the proportion of patients tested for Lynch syndrome (LS) or hereditary breast and ovarian cancer (HBOC) who met testing criteria for the other syndrome.
  
  
  METHODS
  We analyzed a commercial laboratory database of patients tested for LS and HBOC in a clinical setting from 2006 to 2013. Patient cancer histories were analyzed using the 2012 NCCN criteria for LS and the 2013 NCCN criteria for HBOC.
  
  
  RESULTS
  In all, 7% of the patients tested for HBOC met criteria for LS testing. The majority of these patients had a family history of colorectal (30.9%) and/or endometrial cancer (22.7%). Conversely, 29.5% of the patients tested for LS met criteria for HBOC testing. In this group, 30.5% of the patients had a personal history of breast cancer, and 12.6% had a personal history of ovarian cancer.
  
  
  CONCLUSIONS
  Our data demonstrate a substantial phenotypic overlap among patients for multiple common inherited cancer syndromes, which likely complicates diagnosis and test selection. This supports the value of multigene panels to identify pathogenic mutations in the absence of a clinically specific phenotype.
authors: Myriad Genetic Laboratories, Inc., Salt Lake City, Utah, USA.
authors: Jennifer
authors: J
authors: Saam
authors: Christopher
authors: C
authors: Arnell
authors: Aaron
authors: A
authors: Theisen
authors: Kelsey
authors: K
authors: Moyes
authors: Ingrid
authors: I
authors: Marino
authors: Kirstin M
authors: KM
authors: Roundy
authors: Richard J
authors: RJ
authors: Wenstrup
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005820:Genetic Testing / Q000379:methods; D006801:Humans; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D009386:Neoplastic Syndromes, Hereditary / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology*; D010051:Ovarian Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D012189:Retrospective Studies