Abstract ES03-2: Clinical 101: Clinical care of breast cancer in 2013

The clinical care of breast cancer continues to evolve at a rapid pace. While many traditional principles still hold true, advances in the local and systemic management of breast cancer are being incorporated into individualized care of breast cancer patients. In the curative setting (stage I – III), tri-modality therapy with surgery, radiation and systemic therapy continues to be standard of care. In the absence of an absolute contraindication to breast conserving therapy (i.e. inflammatory or multi-centric breast cancer), overall survival remains similar for mastectomy and lumpectomy/radiation therapy. Following mastectomy, radiation to the chest wall and regional nodal lymphatics is generally reserved for patients with T3 (tumor >5 cm) and/or lymph node positive disease. The decision to incorporate systemic therapy is largely driven by breast cancer subtype (i.e. hormone receptor [HR] and HER2 status), stage of breast cancer and general health of the patient. Systemic therapy can either be prescribed pre-operatively (neo-adjuvantly) or post-operatively (adjuvantly) and studies have not shown a survival advantage by order of therapy. Neoadjuvant therapy is commonly reserved for locally-advanced, node positive and/or inflammatory (T4d) breast cancer. Anthracycline and/or taxane-based therapies are recommended for patients with larger tumors (i.e. >2cm) and lymph node positive breast cancer. Chemotherapy and chemotherapy plus HER2-directed (i.e. trastuzumab) therapy is recommended for patients with triple negative and HER2-positive breast cancer of all stages > T1aN0, respectively. In patients with stage I - II HR positive breast cancer, genomic tests (i.e. Oncotype® and Mammoprint®) can be employed to help guide the decision to add chemotherapy to standard endocrine therapy. At least five years of an adjuvant aromatase inhibitor (AI, or combination of an AI and Tamoxifen) is recommended for post-menopausal women with early stage HR-positive breast cancer, while five to ten years of tamoxifen is now recommended for pre-menopausal women with this subtype of breast cancer. Therapy for stage IV breast cancer is palliative and is heavily reliant on systemic therapy, while radiation and surgery are commonly reserved for palliation. In the absence of a visceral crisis, endocrine therapy is mainstay of treatment for patients with advanced HR-positive breast cancer. The addition of mTOR inhibition plus a steroidal aromatase inhibitor has recently been approved following progression on a non-steroidal aromatase inhibitor in this setting. Once patients are refractory to endocrine therapy, chemotherapy is usually prescribed. Presently, stage IV triple negative breast cancer is treated with chemotherapy. While many targeted agents have been investigated (i.e. bevacizumab, PARP and EGFR inhibitors), none are currently FDA-approved for this indication. Finally, the landscape for advanced HER2-positive breast cancer has changed dramatically over the past few years with the approval of lapatinib, pertuzumab, and TDM-1. In closing, the clinical care of breast cancer continues to mature at a rapid pace and advances in care will only continue to improve outcome. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr ES03-2.