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New Approaches to the Treatment of Breast Cancer. Richard G. Pestell, MD, PhD Kimmel Cancer Center Jefferson University Hospitals. INCTR 6th Annual meeting Chennai, India. Unique Point in History. www.cnn.com. Overview. Epidemiology Current therapies
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New Approaches to the Treatment of Breast Cancer Richard G. Pestell, MD, PhD Kimmel Cancer Center Jefferson University Hospitals INCTR 6th Annual meeting Chennai, India
Unique Point in History www.cnn.com
Overview • Epidemiology • Current therapies • Developing therapies • Genetic markers • Nanotechnology • LAG therapy
Breast Cancer -Epidemiology • the most frequently diagnosed malignancy in women (>215,000 in 2004) • the second leading cause of cancer related deaths (>40,000 per year)
Incidence by Year (Jemal et al. CA Cancer J Clin 2005. 55:10.)
Mortality by Year (EBCTCG. Lancet 2005. 365:1687.)
Reproductive Risk Factors • early menarche • late onset of menopause • prolonged use of exogenous estrogen • nulliparity • older age at first pregnancy • breast-feeding
Non-Reproductive Risk Factors • advanced age • history of ADH, LCIS, or DCIS • history of invasive breast cancer • family history of breast cancer • regular alcohol intake • early exposure to ionizing radiation
Genetic Risk Factors • BRCA1 or BRCA2 positivity • p53 mutations (Li-Fraumeni syndrome) • PTEN mutations (Cowden disease)
Palpable Breast Masses CANCER (10%) fibrocystic changes (40%) fibroadenoma (7%) benign NOS (13%) no disease (30%)
Screening Recommendations • routine screening mammogram • every one to two years • age >40 • age <50 and >70 controversial • 17% reduction in mortality (age 40-49) • 26% reduction in mortality (age 50-74)
Prognostic/Predictive Factors • hormone receptor status • Her-2/neu status
Endocrine Therapy • direct correlation between the response to endocrine therapy and hormone receptor status • no documented benefit for patients with truly hormone receptor negative disease
Trastuzumab (Herceptin) • Her-2/neu overexpression in 20 to 25% of all invasive breast cancers • 15% overall response rate (monotherapy) • 30% absolute increase (36% to 62%) in overall response (with chemotherapy)
Early Stage Breast Cancer • operable disease • disease confined to breast + axilla
Early Stage Breast Cancer definitive surgery adjuvant chemotherapy adjuvant radiotherapy adjuvant hormonal therapy
Principles of Adjuvant Therapy • risk of recurrence and death from breast cancer with local therapy alone • 30% with node-negative disease • 75% with node-positive disease
Principles of Adjuvant Therapy • endocrine therapy benefits only those with hormone receptor positive disease • chemotherapy benefits everyone
Endocrine Therapy: Approaches • estrogen receptor modulators • pure anti-estrogens • ovarian ablation or suppression • sex steroids • aromatase inhibitors
Classes of Hormonal Agents • sex steroids • estrogen receptor modulators • aromatase inhibitors • pure anti-estrogens • ovarian ablation or suppression
Menopausal and Hormone Receptor Status 70 60 50 40 % of Patients Premenopausal 30 Postmenopausal 20 10 0 ER+/PR+ ER+/PR- ER-/PR+ ER-/PR- Hormone Receptor Status (Beck, WW. Obstetrics and Gynecology. 1989.)
Hormone Synthesis HYPOTHALAMUS PITUITARY GLAND FSH, LH ACTH Corticosteroids Prolactin OVARIES ADRENAL GLAND Growth Hormone Progesterone Androgens Estrogens Progesterone PERIPHERAL TISSUES Estrogens
Estrogen Receptor Modulators • tamoxifen (Nolvadex) • toremifene (Farnesdon) • raloxifene (Evista)
NONSELECTIVE AI’s aminoglutethimide SELECTIVE AI’s non-steroidal inhibitors anastrozole (Arimidex) letrozole (Femara) fadrozole vorozole steroidal inactivators exemestane (Aromasin) formestane Aromatase Inhibitors
Aromatase Inhibitors: Mechanism of Action Cholesterol Cortisol Pregnenolone Testosterone Androstenedione Progesterone Aromatase InactivatorsandAromatase Inhibitors Aldosterone Estrone Estradiol
Endocrine Therapy: Tamoxifen • no significant advantage to more than five years of therapy • proportional benefits at 10 years • 47% reduction in risk of recurrence • 26% reduction in risk of death (EBCTCG. Lancet 1998. 351:1451.)
Postmenopausal Women: New Standards? • instead of tamoxifen • anastrozole • letrozole • in sequence with tamoxifen • anastrozole • letrozole • exemestane
Premenopausal Women:New Standards? • ovarian functional suppression . . . • instead of chemotherapy • instead of tamoxifen • with tamoxifen • with an aromatase inhibitor
Systemic Therapy: Overview • EBCTCG meta-analyses of the major randomized trials in adjuvant therapy • last published in 2005 (15 year data) • Adjuvant polychemotherapy • Reduction in recurrence 12%,death 10% (<50 yo) • Reduction in recurrence 4%,death 3% 50-69 yo) EBCTG Lancet 2005 365 1687-717
Chemotherapy: Principles • combination chemotherapy is more effective than monotherapy • no significant advantage with more than six months of chemotherapy
Chemotherapy: Principles • proportional reduction in risk was the same irrespective of nodal status • the greater the risk of recurrence or death, the greater the absolute benefit of therapy
Chemotherapy: Benefits • Reduction in yearly death rate: absolute benefits in 10 year survival • Addition of anthracycline effect on death rate • 38% for women <50 years old • 20% for women 50-69 years old • women >70 years old -not represented (EBCTCG. Lancet 1998. 352:930.) EBCTG Lancet 2005 365 1687-717
Anthracyclines • doxorubicin/cyclophosphamide (ACx4) • cyclophosphamide/MTX/5FU (CMFx6) • studies have demonstrated an incremental benefit to anthracycline-containing regimens, particularly with Her-2/neu positive breast cancers • 6 months anthracycline based polychemo- • reduced death rate 38% (<50 yo),20% (50-69 y)
Taxanes • increasing evidence to support the role of taxanes in high-risk disease • AC paclitaxel or docetaxel • docetaxel/doxorubicin/cyclophosphamide (TAC) • doxorubicin/docetaxel • Fluorouracil/epirubicin(100mg)/cyclophosphamide (FEC100) • TAC, FEC100,CEF- greatest reduction in death rate (EBCTCG) EBCTG Lancet 2005 365 1687-717
Trastuzumab: Joint Analysis • 50% patients < 50 years old • 11% node-negative (N9831) • 50% ER/PR positive • 40% T < 2 cm
Trastuzumab: Joint Analysis ACTHH 87% 85% ACT 75% % 67% N Events ACT 1679 261 ACTH H 1672 134 HR=0.48, 2P=3x10-12 DFS Years from Randomization
Trastuzumab: Joint Analysis HR 0.67 (p = .015)
Trastuzumab: HERA • 33% node-negative • 30% 1-3 node-positive • 50% ER/PR positive • 68% received anthracycline • 25% received anthracycline + taxane • 6% received CMF-like chemotherapy
Trastuzumab: HERA 100 Trastuzumab 1 year 90 80 Observation 70 60 % 50 40 HR [95% CI] p value Events 2 y DFS % 30 127 85.8 0.54 [0.43,0.67] <0.0001 20 220 77.4 10 0 0 5 10 15 20 25 DFS Months from randomization 1694 1472 1067 629 303 102 Number at risk 1693 1428 994 580 280 87
New Strategies • Molecular genetics - therapeutic stratification general/specific • target signal transduction • target cell proliferation and function • stimulate the native immune system • promote apoptosis • modulate drug resistance • block angiogenesis • block mechanism invasion / metastasis