Breast and Ovarian Hereditary Cancer Panel, Sequencing and Deletion/Duplication, 20 Genes Indications for Ordering Based on symptoms • For women with any of the following o Breast cancer diagnosed by age 45 o Ovarian cancer o Two primary breast cancers, first diagnosed by age 50 o Breast cancer diagnosed by age 50 with one or more family members with breast cancer o Triple negative breast cancer diagnosed by age 60 o Breast cancer at any age with one or more family members with breast cancer diagnosed by age 50 o Breast cancer diagnosed at any age with two or more family members from the same side diagnosed with breast cancer at any age o Breast cancer at any age with one or more family members with ovarian cancer o Breast cancer diagnosed at any age with two or more family members with pancreatic or prostate cancer o Breast cancer diagnosed at any age and male family member with breast cancer o Breast cancer at any age and Ashkenazi Jewish ancestry • For men with any of the following o Breast cancer at any age o Pancreatic cancer or prostate cancer at any age with two or more family members with breast, ovarian, pancreatic, and/or prostate cancer at any age Based on family history (in asymptomatic patient) • For women with no Ashkenazi Jewish ancestry and family history of any of the following on the same side of the family o Two first-degree relatives diagnosed with breast cancer, one diagnosed at age 50 or younger o Three or more first-degree or second-degree relatives diagnosed with breast cancer regardless of their age o A combination of first- and second-degree relatives diagnosed with breast cancer and ovarian cancer (one cancer type per person) o A first-degree relative with bilateral breast cancer o A combination of two or more first- or second-degree relatives diagnosed with ovarian cancer regardless of age at diagnosis o A first- or second-degree relative diagnosed with both breast and ovarian cancer regardless of age at diagnosis o Breast cancer diagnosed in a male relative • For women with Ashkenazi Jewish ancestry and family history of any of the following o First-degree relative diagnosed with breast or ovarian cancer o Two second-degree relatives on the same side of the family diagnosed with breast or ovarian cancer • For individuals with a family history of a known pathogenic mutation, previously identified in a relative, in one of the genes on the Breast and Ovarian Hereditary Cancer Panel, order targeted mutation testing Test Description • Targeted capture of all coding exons and exon-intron junctions, including the PTEN promoter region, followed by massively parallel sequencing • Sanger sequencing of CHEK2 c.1100delC mutation • Deletion/duplication analysis by tiled, custom-designed comparative genomic hybridization (CGH) array Tests to Consider Primary tests Breast and Ovarian Hereditary Cancer Panel, Sequencing and Deletion/Duplication, 20 Genes 2012026 • Preferred first-tier genetic test for confirmation of hereditary breast and ovarian cancer (HBOC) syndrome • Highest detection rate for HBOC syndrome but also highest likelihood of identifying variants of unknown significance Breast and Ovarian Hereditary Cancer Syndrome (BRCA1 and BRCA2) Sequencing and Deletion/Duplication 2011949 • Acceptable first-tier genetic test for confirmation of HBOC • ~20-60% sensitivity for HBOC syndrome o Only the BRCA1 and BRCA2 genes are assayed Breast and Ovarian Hereditary Cancer Syndrome (BRCA1 and BRCA2) Sequencing 2011954 • ~Up to 90% sensitivity for BRCA1 and BRCA2 mutations Breast and Ovarian Hereditary Cancer Syndrome (BRCA1 and BRCA2) Deletion/Duplication 2011915 • Use if no mutation detected by sequencing • ~10% sensitivity for BRCA1 and BRCA2 mutations • Use to test for known familial BRCA1 or BRCA2 large deletions/ duplications APRIL 2015 | © 2013 ARUP LABORATORIES | ARUP is a nonprofit enterprise of the University of Utah and its Department of Pathology. 500 Chipeta Way, Salt Lake City, UT 84108 | (800) 522-2787 | (801) 583-2787 | www.aruplab.com | www.arupconsult.com Genetics Related tests Ashkenazi Jewish (BRCA1 and BRCA2) 3 Mutations 2011958 • For individuals of Ashkenazi Jewish descent only • 97% sensitivity for BRCA1 and BRCA2 mutations in Ashkenazi Jewish individuals Familial Mutation, Targeted Sequencing 2001961 • Useful when a familial mutation identifiable by sequencing is known Disease Overview HBOC syndrome Prevalence – 1:500 individuals from general population and 1:40 Ashkenazi Jewish individuals has a BRCA1 or BRCA2 mutation • BRCA1 and BRCA2 mutations are believed to cause 20-60% of hereditary breast cancer • 5-10% of all breast cancers and 10-15% of ovarian cancers are caused by BRCA1 or BRCA2 mutations Age of onset • Sporadic breast cancer usually occurs after age 50 • Breast cancer commonly occurs before age 50 in BRCA1 and BRCA2 mutation carriers Symptoms • BRCA1 mutation carriers are at increased risk for HBOC and may also be at increased risk for fallopian, peritoneal, cervical, uterine, pancreatic, and colorectal cancers • BRCA2 mutation carriers are at increased risk for HBOC and may also be at increased risk for pancreatic, stomach, gallbladder, bile duct, and melanoma cancers • Men with BRCA1 mutations are at increased risk for breast cancer and possibly pancreatic, prostate, and testicular cancers • Men with BRCA2 mutations are at increased risk for breast, pancreatic, and prostate cancers Diagnostic issues • Diagnostic testing may allow one to learn if they have a predisposition to develop HBOC and other associated cancers to optimize screening/medical management • Allows asymptomatic family members to learn who is at increased risk Prevention of primary manifestations for BRCA1 and BRCA2 mutation carriers • Prophylactic mastectomy and/or oophorectomy and chemoprevention using tamoxifen • Surveillance for breast cancer screening is a combination of monthly breast self-examinations, annual or semiannual clinical breast examinations, annual mammography, and breast MRI • Ovarian cancer screening is a combination of annual or semiannual pelvic examinations, transvaginal ultrasounds, and measurement of CA-125 concentration • Prostate cancer screening involves annual digital rectal exam and prostate specific antigen testing Genes – see table • Penetrance – female mutation carriers have cumulative cancer risks o For breast cancer – 57% for BRCA1 and 49% for BRCA2 by age 70 o For ovarian cancer – 40% for BRCA1 and 18% for BRCA2 by age 70 Structure/function • BRCA1 and BRCA2 genes function as tumor suppressors that ensure the stability of the cell’s DNA and help prevent uncontrolled cell growth Mutations • Up to 90% of BRCA1 and BRCA2 mutations are detectable by sequencing • Approximately 10% of BRCA1 and BRCA2 mutations are detectable by large deletion/duplication analysis Test Interpretation Sensitivity/specificity • Clinical sensitivity – unknown for the HBOC 20 gene panel • BRCA1 and BRCA2 sequencing and deletion/duplication testing alone detects 20-60% of HBOC (Pruthi, et al, 2010; Meindl, et al, 2011)Analytical sensitivity and specificity of sequencing – 99% and 96%, respectively • Analytical sensitivity and specificity of CGH – 99% Test results • Positive o One pathogenic mutation identified in a gene with autosomal dominant inheritance confirms a diagnosis of HBOC syndrome o Individuals with a pathogenic dominant germ line mutation have a 50% chance of passing the mutation on to their offspring o Two pathogenic mutations located on opposite chromosomes in an autosomal recessively inherited gene confirm a diagnosis of HBOC syndrome o One pathogenic mutation in an autosomal recessively inherited gene confirms carrier status for HBOC syndrome • Negative o No pathogenic mutations detected in any of the genes tested reduces the likelihood of, but does not exclude, a diagnosis of HBOC syndrome as not all mutations in the tested genes are identified and not all predisposing genes are interrogated • Inconclusive o Variants of unknown clinical significance may be identified APRIL 2015 | © 2013 ARUP LABORATORIES Limitations • The following will not be determined or evaluated o Deep intronic and regulatory mutations o Breakpoints for large deletions/duplications o Sequence changes in EPCAM o Exons 11-15 of CHEK2 will not be evaluated with the exception of the c.1100delC mutation o Deletions/duplications Exon 1 in CDH1, MSH2, and RAD51D Exons 4,6, and 7 in STK11 Exon 8 in PTEN Exon 12 in ATM • Small deletions or insertions may not be detected • Diagnostic errors can occur due to rare sequence variations Gene Symbol ATM Gene Name NM # References • Ford D, et al. Genetic heterogeneity and penetrance analysis of the BRCA1 and BRCA2 genes in breast cancer families. The Breast Cancer Linkage Consortium. Am J Hum Genet. 1998 Mar;62(3):676-89 • Lalloo F, Evans DG. Familial breast cancer. Clin Genet 2012; 82:105 • Meindl A, Ditsch N, Kast K, et al. Hereditary breast and ovarian cancer: new genes, new treatments, new concepts. Dtsch Arztebl Int. 2011 May;108(19):323-30 • Pruthi S, Gostout BS, Lindor NM. Identification and Management of Women with BRCA Mutations or Hereditary Predisposition for Breast and Ovarian Cancer. Mayo Clin Proc. 2010 Dec;85(12):1111-20 • Walsh T, Casadei S, Lee MK, et al. Mutations in 12 genes for inherited ovarian cancer, fallopian tube, and peritoneal carcinoma identified by massively parallel sequencing. PNAS 2011;108:18032 OMIM # Inheritance Cancer Association 000051.3 607585 AD Breast BARD1 BRCA1 Ataxia telangiectasia mutated (includes complementation groups A, C and D) BRCA1- associated RING domain gene 1 Breast cancer 1 000465.2 007294.3 601593 113705 AD AD BRCA2 Breast cancer 2 000059.3 600185 AD BRIP1 BRCA1 interacting protein C-terminal, helicase 1 Cadherin 1, E-cadherin (epithelial) CHK2 checkpoint homologue (S. pombe RAD53) Epithelial cell adhesion molecule Multiple endocrine neoplasia 1 032043.2 605882 AD Breast, neuroblastoma Breast, ovarian, fallopian, peritoneal, pancreatic, prostate Breast, ovarian, fallopian, peritoneal, pancreatic, prostate, gallbladder, gastric, melanoma Breast, ovarian 004360.3 007194.3 192090 604373 AD AD Gastric, breast, prostate Breast, colorectal, prostate 002354.2 130799.2 185535 613733 AD AD 000249.3 120436 AD 000251.2 609309 AD MSH6 MutL homologue 1, colorectal cancer, nonpolyposis type 2 (E. coli) MutS homologue 2, colorectal cancer, nonpolyposis type 1 (E coli) MutS (E.coli) homologue 6 000179.2 600678 AD MUTYH MutY homologue (E.coli) 001128425.1 604933 AR, AD NBN PALB2 PTEN Nibrin (NBS1) Partner and localizer of BRCA2 Phosphatase and tensin homolog 002485.4 024675.3 000314.4 602667 610335 601728 AD AD AD Colorectal, ovarian Glucagonomas, gastrinomas, VIPomas, thymic, bronchial, gastric, breast Ovarian, colorectal, endometrial, bladder, kidney Ovarian, colorectal, endometrium, bladder, kidney Ovarian, colorectal , endometrium, bladder, kidney Colorectal (AR), gastric, breast, duodenal, endometrium (AD) Breast, ovarian Breast, pancreatic Thyroid, breast, endometrial RAD51C RAD51D STK11 TP53 RAD51 homolog (S. cerevisiae) RAD51D homolog D (S. cerevisiae) Serine/threonine kinase 11 (LKB1) Tumor protein 53 058216.1 002878.3 000455.4 000546.5 602774 602954 602216 191170 AD AD AD AD CDH1 CHEK2 EPCAM MEN1 MLH1 MSH2 AD = autosomal dominant ; AR = autosomal recessive APRIL 2015 | © 2013 ARUP LABORATORIES Breast, ovarian Breast, ovarian Colorectal, pancreatic, breast, ovarian Breast, ovarian, brain, soft tissue and osteosarcomas, gastrointestinal, leukemia, lymphoma, adrenocortical carcinoma
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