Updates in Breast Cancer Genetics
Jennifer Klemp, PhD, MPH Assistant Professor of Medicine, Division of Oncology Cancer Risk & Genetic Counseling Director, Cancer Survivorship Founder/CEO, Cancer Survivorship Training, Inc www.cancersurvivorshiptraining.com February 2014 This Workshop will Address the following: Many young women diagnosed with breast cancer make the decision to undergo genetic testing. In this session, you will hear about the genetics of breast cancer in young women and what information testing can provide. Also, our expert will discuss how and when genetic counseling can be useful– a first step toward understanding your individual and family risk including heredity and genetics. Learning Objectives
The presentation will enable the participant to:
1. Risk Factors and Genetic Testing
2. Risk Estimation Models and Counseling
a. Implications for you and your family
3. Screening Recommendations
4. Standard Risk Reduction Approaches
Who is at high risk for cancer?
Assessing Risk Major and Minor Risk Factors
Major Risk Factors Minor Risk Factors >2-fold increase in risk >1 but <2-fold increase in risk Known germline mutation (ie. Early menarch (<12) BRCA1 or BRCA2 mutation) Nullparity/Late age of 1st live birth 1st degree relative (younger <50) Late menopause Chest radiation (<30y/o) Family history: multiple relatives including 2nd & 3rd degree Prior DCIS, LCIS, Atypia Combined estrogen & progestin Prior breast or ovarian cancer Serum hormones: sex hormones, Age >60 SHGB, insulin/growth factors Obesity/Inactivity Alcohol consumption Major Risk Factors: Risk Per Year
Major Risk Factor Absolute Risk Relative Risk BRCA 1 or BRCA2 1-2% 10-20X Chest XRT <30 1-2% 10-20X DCIS (lump + XRT) 1% 10X LCIS 1% 10X Atypia & Family Hx 1% 8-10X Atypia 0.5% 4-5X Prior Invasive BrCa 0.75% 5-8X Age >60 (vs. age 30) 0.33% 10X Breast Cancer Risk Factors
16 14 Relative Risk 12 10 8 6 4 2 0 BRCA1or In-situ AH + FH AH HRT Early 1st Birth Obesity 2 Menarche Chance of Being at High/ Hereditary Risk
5-10% hereditary 10-15% familial
75-85% sporadic
BRCA1/2 Mutations Responsible for a majority of “Hereditary Breast Cancers” Total Hereditary Breast Cancer
BRCA1 or BRCA2 (>50-85%)
Next Generation (15-30%)
Hereditary vs Familial vs Sporadic Hereditary Familial Clustering
Ov, 52 Br, 67
Br, 71
Br, 32 Br, 45 2 Breast cancers under 50 Br, 58 and ovarian cancer, Multiple generations, 50% Sporadic women affected Br, 63
Br, 71 Autosomal Dominant Pattern of Inheritance
50/50 Chance of inheriting Genetic mutation
Affected Normal Father Mother
Affected Normal Affected Normal Daughter Son Son Daughter Newly Diagnosed Capture Rate: 34% Leads to Survivor Patient Population AT RISK
Missed Patients Y5
Missed Patients Y4
Missed Every year, more patientsPatients Y3are missed than tested
Missed 1. Surveillance, Epidemiology, and End Results (SEER), Patients Y2 National Cancer Institute, 2012. http:// seer.cancer.gov/statistics/ 2. Eisenbraun et al. Hereditary Breast and Ovarian Cancer testing: integration and outcomes within Large Survivor community oncology practices. Comm Oncol. Missed 2010;7:75-81. 3. NCCN Clinical Practice Guidelines in Oncology v. Patients 4.2013 Genetic/Familial High-Risk Assessment: Patient Population Breast and Ovarian. Accessed at www.nccn.org Y1 4. Kerber RA, et al. Frequency of familial colon cancer and hereditary nonpolypsosis colorectal cancer (Lynch syndrome) in a large population database. Familial Cancer 2005;4:239-44. 5. Internal Myriad data National Capture Rate of Total At-Risk Patients = 20%
BRCA Mutations Increase Risk of 2nd Primary Cancers BRCA1-Associated Cancers: Risk by age 70
Breast cancer 50-85% (often early age at onset)
Second primary breast cancer 20%-60%
Ovarian cancer 15-45%
Possible increased risk of other cancers
JCO 2004;22: 735-42; NCI 2005 BRCA2-Associated Cancers: Risk by age 70
Breast cancer Breast cancer (50-85%) (6%)
Second primary breast cancer (20-60%)
Ovarian cancer (10-27%) Prostate (20%)
Increased risk of pancreatic cancer and melanoma
JCO 2004;22: 735-42; NCI 2005 Next Generation/Multi-Gene Cancer Panels
1. Many patients with suggestive family histories test negative on standard testing a. Need for additional/expanded screening
2. Patients do not meet classic guidelines for hereditary cancer syndromes a. Variable expressivity and reduced penetrance
3. Many genes implicated in cancer a. Testing multiple genes simultaneously can be more time and cost effective
4. Overlapping phenotypes of different hereditary cancer syndromes
Next Generation/Multi-Gene Testing
• Currently moving from research to clinical Sample Panel: BRCA1/2, ATM, BARD1, BRIP1, CHEK2, – Research: limited eligibility CHD1, EPCAM, MLH1, MSH2, – Clinical: turn around time (pre-certification & testing) MSH6, MRE11A, MUTYH, NBN, PALB2, PMS1, PMS2, PTEN, – If positive: Lack of formal risk and surveillance recommendationsRAD50, RAD51C, STK11, TP53 • More likely to identify moderate-low penetrance genes – High number of variants of uncertain significance (VUS) • Free, accessible, public archive of reports of the relationships among human variations and phenotypes, with supporting evidence • ClinVar: http://www.ncbi.nlm.nih.gov/clinvar/ • Sharing Clinical Reports Project (SCRP): http://sharingclinicalreports.org/index.html – Patient or Provider submission + reimbursement • LATER – Whole genome sequencing • Analysis of entire genetic makeup of an individual – Whole exome sequencing • Analysis of all coding regions of genetic material NextGen Testing: Who to test??
Cast the net widely, test nearly Test Selectively anyone • Pro • Pro — Higher penetrance — No sure approach for families excluding anyone — Easier to interpret and — Find more mutation carriers recommend • Con management — Difficult to interpret and • Con develop management — Missed mutations recommendations
Always test the relative with the highest mutation probability in the family Reduce non-informative negative results Testing Process
• Pre-test Counseling/Informed Consent — Possible results — Discuss VSB/VUS — Cancer risks — Clinical management — Costs/Pre-certification/Financial assistance • Post-test Counseling — Disclose/Discuss — Management plan — Implication for the family • Maintain contact files • Notify patients with variants are reclassified Rare changes in other genes associated with breast cancer.
GENE DESCRIPTION PTEN Helps regulate cell growth. Causes Cowden syndrome leading to higher risk of both benign and cancerous tumors in the breast, digestive tract, thyroid, uterus, and ovaries. TP53 Provides instructions for making a protein to stop tumor growth. Causes Li-Fraumeni syndrome and increases soft tissue cancer at young ages and higher risk of BrCa, leukemia, brain tumors, and sarcomas. CHEK2 Provides instructions for making a protein to stop tumor growth. Causes Li-Fraumeni syndrome and can double breast cancer risk. CHD1 Supports protein growth that helps cell adherence and tissue formation. Increased risk of lobular BrCa and rare, early onset stomach cancer. PALB2 Supports protein growth that works with the BRCA2 protein to repair damaged DNA and stop tumor growth. Doubles BrCa Risk. Inheriting 2 abnormal PALB2 genes causes Fanconi anemia, higher risk of cancer, including kidney cancer and brain cancer ATM Helps repair damaged DNA. Linked to increased risk of BrCa Li-Fraumeni Syndrome Cowden Syndrome Not all Labs are created equally: BRCA1/2 & Panel Testing Options Risk Counseling & Testing ( For BRCA1/2 Mutations)
Triple Negative Breast Cancer (TNBC) 207 patients with stage I-IV triple negative BrCa underwent Comp BRCA1/2 testing n Deleterious germline mutation in BRCA1 in 11.1% (23/207) and BRCA2 in 4.3% (9/207) of the patients, respectively, giving an overall prevalence rate of 15.4% (32/207).
n Mutation rates in patients with or without SFH was 32.5% and 6.1%, respectively. When examined by age at diagnosis, the mutation rates were: 27.6% <50), 11.4% (51-60), and 4.9% (>61). If SFH or age <50, were the only criteria used 25% and 34% of mutations would have been missed.
Sharma P, Klemp JR, et al., Prospective evaluation of BRCA mutations in a large triple-negative breast cancer (TNBC) registry: Implications for germ line testing. Abstract accepted for a oral poster presentation ASCO, Chicago, IL, 2013. Results TNBC and Hereditary BrCa
n 77 TNBC from MD Anderson – Unselected for age and family history n 18.2% had deleterious germline mutations in BRCA1 or BRCA2 n Mutation carriers had better 5-year recurrence free survival (p = 0.016)
Gonzales-Angulo TNBC and Hereditary BrCa Cont…..
n 199 TNBC from community network – Unselected for age and family history
n 10.6% found to have a deleterious mutation in BRCA1 or BRCA2
n Higher prevalence of BRCA2, not BRCA1 (unlike previous report)
Hartman, AR Comparison- NCCN Guidelines What About DCIS? n Ductal carcinoma in situ (DCIS; also known as intraductal carcinoma) is the most common type of non-invasive breast cancer n About 1 in 5 new breast cancer cases will be DCIS n NCCN and Medicare criteria – Both include DCIS as an equal cancer to invasive breast cancer when considering who should get testing for BRCA1 or BRCA2
Cancer Risk Counseling and Genetic Testing
“Who, When Why, and What?” Who to Test For BRCA1/2 n Have Breast Cancer and n No Breast Cancer but – Onset
Why Test For BRCA1/2 n Have Breast Cancer n No breast Cancer – May affect choice of – Breast screening surgery and starts at 25, reconstruction insurance pays for – Prophylactic TLH/ MRI BSO – Ovarian screening at – Additional cancer risk/ 30-35 with TV US screening options – Prophylactic TLH/BSO – Implications for after childbearing relatives complete or 35 NCCN Recommended Management Reduces Cancer Risk Assists with surgical management decisions n Surgery: – Breast n Lumpectomy vs. Mastectomy n +/- Prophylactic mastectomy – ↓ risk by up to 90-95%
– Ovaries n Risk Reducing Salpingo-oophorectomy + fallopian tubes – +/- uterus (↓ risk by >95%) – ↓ risk of breast cancer by 50-70% – ↓ risk of ovarian cancer by > 95% – 15% Survival Advantage Probable for BRCA1/2 Carriers – Cost Effective Assists with screening and treatment decisions n Long-term screening – More intensive n Chemotherapy (under investigation) – Triple-negative BrCa (response to treatment) – Use of PARP inhibitor What to Do With Equivocal or Non-Informative Results n Breast Cancer and n No Breast Cancer and BRCA Mutation No or uncertain Uncertain significance mutation. Affected in patient and other Carriers not tested affected relatives – Unclear – Screening and – Screening and prophylaxis as prophylaxis as dictated by clinical dictated by clinical picture picture Screening for High Risk Women Breast Screening Recommendations
Intervention Average High Risk BRCA 1/2 Risk Mutation Annual Mammography Beginning by 5 -10 years prior to Age 25 age 40 age of onset youngest relative Clinical Breast Annual Annual or as Semi-Annual Examination clinically indicated Add Breast MRI No Yes if familial risk. Yearly > 20% Add ultrasound As clinically As clinically Yes — if indicated indicated MRI not covered by Insurance Ovarian Cancer Screening Recommendations
Intervention Average High Risk BRCA 1/2 Risk Mutation Pelvic Ultrasound Not No Annual or semi- with doppler probe indicated (Yes, if familial annual cancer risk and + family history) CA-125 blood test Not No Annual or semi- indicated (Yes, if familial annual cancer risk and + family history) Pelvic Examination Annual Annual Annual or semi- annual YES YES YES Additional Recommendations
Intervention Average High Risk BRCA 1/2 Risk Mutation Chemoprevention Not Consider Tamoxifen Consider Tamoxifen indicated or Raloxifene or or Raloxifene or Aromasin Aromasin or Clinical Trials or Clinical Trials Prophylactic Surgery Not Possibly, but not Consider, indicated common significant risk reduction + survival benefit Weight Control YES YES YES Increase Physical YES YES YES Activity Limit EtOH intake YES YES YES Case Study: Beth
Beth is a 38 year old woman recently diagnosed with triple negative breast cancer and is trying to determine her course of treatment. She has two young children (5 & 3 y/o), but also two female siblings. Beth reports the following family history: – Maternal family history is negative for cancer – Paternal family history is significant for: n Her father has one brother & one sister n Limited Family Structure n Paternal grandmother diagnosed with breast cancer age 52, but she thinks she was pre- menopausal
Case Study: Triple Negative BrCa
German English/Irish
⁄ 88 Dx 72 Dx 52
62 64 Dx 48 62 60 BRCA1/2 Neg Key -Breast CA 32 Beth Dx 38 Triple Neg 37 28 -Ovarian CA -Prostate CA
5 3 -Pancreatic CA Case Study: BRCA1/2 Risks
n Rational for Testing: – Testing will assist with informed treatment decision making (ASCO Guidelines) – Early age of Onset and Triple negative BrCa (NCCN guidelines) n Limited family structure n Paternal Aunt tested Negative for BRCA1/2 Genetic counseling & testing prior to definitive surgery and for treatment planning. Case Study: Updated Pedigree
German English/Irish
⁄ 88 Dx 72 Dx 52
62 64 Dx 48 62 60 BRCA1/2 Neg Key -Breast CA 32 Beth Dx 38 Triple Neg 37 28 BARD1+ -Ovarian CA -Prostate CA
5 3 -Pancreatic CA Case Study: Impact of results – medical management
n Beth – BARD1+: Moderate BrCa risk – Discuss surgical management including: n Breast conservation n Therapeutic and Preventive Mastectomy – Discuss whether she has completed child- bearing n Options for fertility preservation – Risks for other cancers Case Study: Impact of results – medical management
n Beth’s 1st degree relatives: sisters & father – Discuss results (duty to warn) and encourage genetic counseling and testing – If negative, General population risk for breast cancer –follow standard screening (ACS) guidelines n Cannot pass this on to their children – If positive, elevated risk for breast cancer- follow NCCN guidelines n Beth’s children: – Genetic counseling and testing at the appropriate time/age Case Study: Take Home Messages
n Risk assessment and genetic testing gives information to patient AND family members – Some family members may want this information and some may not n Genetic testing, when informative, can help individuals make decisions about early detection and risk-reduction n Can also relieve anxiety about cancer risk (if negative) n Informed decision-making imperative n Additional follow-up support and/or counseling sometimes necessary Alternative Cancer Risk Assessment Tests Direct to Consumer Marketing
Entice the purchase and use of tests directly to consumers http://www.navigenics.com/ through advertising http://www.decode.com/ n 960,000 specific single- nucleotide polymorphism (SNPs) n Reports on 240+ health conditions and traits n Testing for 40+ inherited conditions n Discover your ancestry composition n Updates on your DNA as science advances n Eventual goal: whole genome sequencing http://www.23andme.com
Thank You For Your Time
QUESTIONS?