Update on genetic testing for hereditary breast cancer syndromes Kristin DePrince Mattie, M.S. Licensed / Certified Genetic Counselor William G. Rohrer Cancer Genetics Program

Objectives Describe current approaches to genetic testing for hereditary cancer syndromes. Identify potential benefits and limitations of the multi-gene panel testing approach for hereditary cancer syndromes. Focus on breast cancer

Breast cancer risk factors Non-modifiable / Intrinsic Female gender Increasing age Personal history of breast cancer Family history of breast cancer Hereditary cancer syndrome Increased breast density Race / ethnicity Breast biopsy pathology Modifiable / Extrinsic Radiation to the chest Multiple biopsies Estrogen and progesterone exposure Hormone replacement therapy Birth control pill use Lifestyle factors

Image from All cancers are genetic, but most are NOT hereditary. Sporadic (~70%) –environmental exposures / random chance Familial (~20%) –shared environmental exposures –similar genetic background Hereditary (~10%) –inherited genetic mutation » increased risk

BRCA1/BRCA2 mutations increase the risk for multiple cancers: female and male breast, ovary, prostate, pancreas, skin (melanoma), gall bladder, bile duct, stomach, fallopian tube, etc. Causes of breast cancer

Hereditary cancer syndrome concepts Inheritance – usually autosomal dominant Penetrance – high / moderate / low Variable expression cancer dx relatively younger – usually adult onset Gender specific cancer risks Germline genetic testing – not always available – rely on clinical diagnosis as needed – not always informative for a family Image from Genetics Home Reference: ovarian-genetics-pdq

80 Bilateral & 52 Sporadic FamilialHereditary

NCCN Guidelines Version : Guidelines for Detection, Prevention and Risk Reduction: Genetic/Familial High-Risk Assessment: Breast and Ovarian.

Select NCCN evaluation/referral criteria Breast cancer HBC syndrome in family Early age at dx (≤50y) Triple negative dx ≤ 60y ≥2 primary breast cancers Male gender Ashkenazi Jewish ancestry Otherwise depends on strength of family history Ovarian cancer Epithelial v. non-epithelial Fallopian & 1 ˚ peritoneal Family history only 1 st or 2 nd degree relative w/ breast ca. dx ≤ 45y Close (1 st, 2 nd, 3 rd degree) relative meeting certain criteria, such as: – Ovarian cancer – Male breast cancer – HBC syndrome – Breast cancer depending on strength of family history NCCN Guidelines Version : Guidelines for Detection, Prevention and Risk Reduction: Genetic/Familial High-Risk Assessment: Breast and Ovarian.

Evolution of hereditary breast cancer (HBC) genetic testing Who performs the testing (commercially)? – Before June 2013 BRCA1/BRCA2 only via Myriad Genetic Laboratories Other HBC genes by other labs as indicated – June present Any lab can test BRCA1/BRCA2 or any other HBC gene Which genes are tested? – Before 2012 Usually just BRCA1/BRCA2, Other HBC genes (such as CDH1, PTEN, TP53) as indicated by personal / family history – 2012 – present Next generation sequencing Multi-gene panels vs. single syndrome testing

Current genetic testing practices Syndrome- or gene-specific testing Typically single gene or single syndrome testing – i.e. BRCA1 & BRCA2 genes only; PTEN only; CDH1 only; etc. Single-site testing for known familial mutation Multi-gene testing (“panel testing”) Variable number of genes tested Pan-cancer versus single cancer gene panels – Hereditary breast / colon / uterine / ovarian / pancreatic / skin / etc. cancer gene panel – Hereditary breast cancer gene panel Genes can be selected based on level of known cancer risk – High / moderate / “increased” risk levels

High risk ≥30% Moderate risk <30% “Increased risk” genes still need further study to better define risks Hereditary mutations in other genes may also increase breast cancer risk Mutations in these genes may also increase the risk for other cancer types hp/breast-ovarian-genetics-pdq hp/breast-ovarian-genetics-pdq Image used with permission from Ambry Genetics _breast_cancer_clinician_brochure.pdf _breast_cancer_clinician_brochure.pdf Use of this image does not imply endorsement.

Considerations regarding multi-gene testing Increased mutation detection rate Lower chance of “uninformative” negative results for a family Often more cost- & time- efficient May find a mutation in more than one gene Unexpected results Limited data re: cancer risks for some genes Lack of standard medical guidelines for some genes Variants of unknown significance Insurance companies consider multi-gene panels “investigational” Unexpected results Potential advantagesPotential disadvantages NCCN Guidelines Version : Guidelines for Detection, Prevention and Risk Reduction: Genetic/Familial High-Risk Assessment: Breast and Ovarian.

Genetic test result classifications No Mutation (Negative ) VUS- Likely Benign Uncertain Significance (VUS) VUS- Likely Pathogenic Pathogenic (Positive) Medical management based on personal and family history. Uncertain results do not influence recommendations for care. Medical management based on cancer risks linked with gene where mutation found. Slide from COGENT University of Pennsylvania

NCCN Guidelines Version : Guidelines for Detection, Prevention and Risk Reduction: Genetic/Familial High-Risk Assessment: Breast and Ovarian.

Frequency of Mutations in Individuals with Breast Cancer Referred for BRCA1 and BRCA2 Testing Using Next- Generation Sequencing With a 25-Gene Panel (N. Tung et al., Cancer 2015;121:25-33.) Cohort 1: No prior BRCA testing n= women, 22 men, 9 gender unspecified no Ashkenazi Jewish patients 241 (13.5% of total) mutation (+) (includes 7 men) – 162 (67%; 9% of total) BRCA1/BRCA2 (+) – 76 (32%; 4.3% of total) at least 1 mutation in a non- BRCA gene – 3 (1%) with mutations in BRCA2 and another gene (ATM, CHEK2 or NBN) Cohort 2: Prior BRCA negative result n= women, 3 men 94 reported AJ ancestry 14 (3.7%) mutation (+) – Similar to 4.3% (+) rate in Cohort 1 (76/1781) – None male – None with AJ ancestry – one woman with mutations in both BARD1 and ATM

Frequency of Mutations in Individuals with Breast Cancer Referred for BRCA1 and BRCA2 Testing Using Next- Generation Sequencing With a 25-Gene Panel (N. Tung et al., Cancer 2015;121:25-33.) Genes tested: BRCA1, BRCA2, TP53, CDH1, PTEN, ATM, CHEK2, STK11, RAD51C, PALB2, BARD1, BRIP1, NBN, MLH1, MSH2, MSH6, PMS2, EPCAM, RAD51D, APC, MUTYH, CDKN2A, SMAD4, CDK4, BMPR1A Most frequent non- BRCA1/BRCA2 mutations: CHEK2, ATM, PALB2 The frequency of mutations in genes other than BRCA1/BRCA2 was lower in Ashkenazi Jews compared with non-Ashkenazi individuals 41% of individuals (both cohorts) had at least 1 VUS

CLINICAL CASES (2)

Maternal Ancestry: European, non-Jewish PALB2: breast, pancreas, ?ovarian, ?male breast cancers 70 adopted (triple negative) s/p BL mastectomy Genetic testing BL & Single site testing: PALB BRCA1/BRCA2: negative Genetic testing gene panel : PALB2+

Ancestry: Maternal Black Paternal Caucasian CDH1: diffuse gastric and lobular breast cancers, colon cancer in some families (lobular) s/p BL mastectomy Genetic testing Lung HBC 14 gene panel : CDH1+

Cancer Genetics Program Team Oncologists Generosa Grana, MD Program Director Alexandre Hageboutros, MD Polina Khrizman, MD Marjan Koch, MD Pallav Mehta, MD Jamin Morrison, MD Kanu Sharan, MD Robert Somer, MD Preeti Sudheendra, MD Genetic Counselors Janice Horte, MS Brooke Levenseller Levin, MS Kristin DePrince Mattie, MS Jennifer Stone, MS Program Staff Manager Evelyn Robles-Rodriguez, RN, MSN, APN, AOCN Medical Assistants Brandi Ford, CMA Myra Salcedo, CMA Administrative Coordinator Vicki Kay Atkinson

Genetic evaluation practice locations Patients may call 855-MDA-COOPER ( ) for scheduling 2 Cooper Plaza, 400 Haddon Ave., Camden 900 Centennial Blvd., Voorhees