Introduction to Breast Cancer

Introduction to Breast Cancer Ann Williams, MD 2010 General Considerations • Most challenging solid tumor – Marked heterogeneity (different types) • Hormone receptors – 60-70% positive – Predicts efficacy of hormone therapy • Her-2-neu oncogene – 20% positive – Predicts efficacy of anthracycline, taxanes and Trastuzumab (Herceptin) General Considerations • Nodal status – Historically the single best predictor of recurrence – Will become less important • Gene array studies – May replace nodal status in the future – Prognostic – Predictive of response to therapy General Considerations • Long natural history – 3% of 20 year survivors develop stage IV disease • Rapidly changing knowledge base – Numerous clinical trials possible due to large numbers of patients Epidemiology • Reproductive factors – – – – – – Age at first birth- younger decreases risk Parity- higher decreases risk Lactation- longer decreases risk Age at menarche- younger increases risk Age at menopause- older increases risk Postmenopausal estrogen use increases risk Epidemiology • Lifestyle factors – Obesity, increases risk – Exercise, more decreases risk • Genetics – Accounts for about 10% of breast cancer in US • BRCA1-2 account for most – Unknown in Viet Nam Screening • Reduces breast cancer mortality by 30% – Has been routine in US since mid 1980’s • Routine mammography every 1-2 years for women over 50, or over 40 with risk factors • Breast MRI for very high risk women (genetic carriers) Prevention • Modify risk factors • Prophylactic Tamoxifen or Raloxifen – Both reduce the risk of ER positive invasive breast cancer by 50% in high risk healthy women – Characteristics of patients enrolled in these trials • Over 60 • History of lobular carcinoma in situ • Family history of breast or ovarian cancer Prevention • Prophylactic mastectomy for mutation carriers • Prophylactic oophorectomy in mutation carriers Diagnosis • Abnormal screening mammogram, not palpable – Ultrasound guided core needle biopsy – Wire guided lumpectomy – MRI guided core needle biopsy • Palpable mass or other physical findings – Core needle biopsy-Allows receptor determination preoperatively – FNA Adjuvant systemic therapy • Impact of chemotherapy – Small subsets gain major benefit (ER negative, Her-2-neu positive) – Most patients gain little • Her-2-neu overexpressed – 3+ ICC positive – FISH (fluorescence insitu hybridization) positive – Use one year of Herceptin (Trastuzumab) for all node positive and high risk node negative Adjuvant systemic therapy St Gallen 2009 Consensus • Endocrine-Any ER/PR staining • Traztuzumab->30% intense or complete staining by IHC or FISH positive • Chemotherapy– Her-2 positive – Triple negative – HR+, Her-2 negative-selectively Adjuvant systemic therapy St Gallen 2009 Consensus • Relative indications for chemotherapy in HR+, Her-2 negative – – – – – – – Weak ER or PR Grade High proliferation Presence of extensive perivascular infiltration >3 positive nodes Tumor > cm High risk gene assay ... Inflammatory Breast Cancer • Neoadjuvant chemotherapy to maximal response (4-6 cycles) • Breast conservation may be possible in locally advanced breast cancer • Mastectomy still advised for inflammatory,... operable breast cancer • Lumpectomy and Radiation – Contraindications • Diffuse malignant calcifications on mammogram • Tumor in more than one quadrant of the breast • Tumor size compared to breast. .. • Over 60 • History of lobular carcinoma in situ • Family history of breast or ovarian cancer Prevention • Prophylactic mastectomy for mutation carriers • Prophylactic oophorectomy in mutation