RT Book, Section
A1 Petersen, Gloria M.
A1 Codori, Ann-Marie
A2 Valle, David L.
A2 Antonarakis, Stylianos
A2 Ballabio, Andrea
A2 Beaudet, Arthur L.
A2 Mitchell, Grant A.
SR Print(0)
ID 1181416740
T1 Genetic Testing for Familial Cancer
T2 The Online Metabolic and Molecular Bases of Inherited Disease
YR 2019
FD 2019
PB McGraw-Hill Education
PP New York, NY
SN 9780071459969
LK ommbid.mhmedical.com/content.aspx?aid=1181416740
RD 2024/04/16
AB Cancer  gene  discoveries  have  led  to  important  changes  in  the  clinical  practice  of  cancer  risk  assessment.  Genetic  tests,  in  conjunction  with  family  history  information,  can  be  used  to  a)  clarify  the  diagnosis  of  inherited  cancer  syndromes  in  patients  with  tumors  and  b)  provide  information  about  cancer  susceptibility  to  asymptomatic  persons  in  high-risk  families.  The  promise  of  cancer  gene  testing  is  reduced  cancer  incidence  and  mortality  through  directed  prevention  and  screening.In  addition  to  the  medical  and  health  benefits  of  cancer  gene  testing,  the  power  to  identify  high-risk  persons  has  led  to  considerable  discussion  of  the  implications  from  consumer,  epidemiologic,  technologic,  ethical,  legal,  policy,  psychological,  and  genetic  counseling  perspectives.Cancer  gene  testing  can  include  a  variety  of  modalities,  including  linkage,  direct  detection  when  the  mutation  is  known,  and  mutation  analysis,  such  as  protein  truncation  test  or  sequencing.  In  addition,  tests  for  microsatellite  instability  in  colon  tumors  and  gene  expression  assays  may  provide  indirect  evidence  supporting  a  diagnosis  of  hereditary  nonpolyposis  colorectal  cancer.Commercial  availability  of  germline  cancer  gene  tests  (i.e.,  BRCA1,  BRCA2,  APC,  hMSH2,  hMLH1,  p16,  NF2)  has  outpaced  the  awareness  among  health  professionals  of  the  need  for  careful  implementation  of  testing  algorithms  and  patient  education  on  the  issues.Surveys  of  persons  at  varying  risks  for  cancer  show  that  most  persons  are  interested  in  having  a  gene  test.  The  actual  uptake  of  cancer  gene  testing  has  been  more  modest;  the  decision  to  undergo  gene  testing  is  influenced  by  psychosocial  factors,  including  perception  of  cancer  risk,  perceived  ability  to  cope  with  gene  test  results,  depression,  and  fear  of  insurance  discrimination.  Among  persons  who  are  tested,  there  appears  to  be  no  significant  short-term  (1–3  months)  psychological  distress  following  disclosure  of  results.Cancer  genetic  risk  assessment  is  a  multistep  process  and  incorporates  medical,  psychological,  genetic,  and  counseling  dimensions.  Clinical  indications  and  a  model  algorithm  for  cancer  risk  assessment  and  gene  testing  are  provided.  For  persons  who  are  at  risk  for  cancer,  gene  test  interpretation  will  depend  upon  whether  the  specific  germline  cancer  gene  mutation  is  known  for  the  family.  Careful  evaluation  of  the  pedigree  for  characteristic  aggregation  of  tumor  types  among  affected  individuals  and  availability  of  affected  persons  for  testing  are  important  issues  in  implementing  genetic  testing.Health  professionals  will  need  to  be  aware  of  the  variety  of  issues  that  contribute  to  the  process  of  helping  patients  to  understand  their  risk,  make  informed  decisions,  and  appreciate  the  implications  for  cancer  prevention  and  risks  for  other  family  members.  Genetic  counseling  is  an  essential  component  of  cancer  genetic  risk  assessment  services.