Locally Advanced Breast Cancer

Abstract

Abstract Locally advanced breast cancer encompasses a heterogeneous collection of breast neoplasms and constitutes approximately 10%-20% of the newly diagnosed breast cancers. These cancers may have widely different clinical and biological characteristics. Patients with these tumors may be classified as stage IIB, III or IV breast cancer according to the American Joint Committee for Cancer Staging and End Results Reporting (TNM classification). Multidisciplinary therapy has become the treatment of choice for these patients. Primary or neoadjuvant chemotherapy followed by locoregional therapy, either surgery and/or radiotherapy, and postoperative systemic chemotherapy is now an accepted strategy. More than 70% of patients achieve an objective response (including pathological complete remission in 10%-25% of cases), and many patients experience downstaging through primary chemotherapy. Breast conservation is possible in 10%-40% of patients with locally advanced breast cancer; almost all patients initially are rendered disease-free, and long-term local control is achieved in over 70% of these patients. Primary chemotherapy is the initial choice of treatment for patients with locally advanced tumors, but it is unclear what the optimal sequence of subsequent therapies should be, whether one or two local treatment modalities are necessary, and whether any or different postoperative chemotherapy is needed. The efficacy of primary chemotherapy was demonstrated in several large prospective studies in patients with locally advanced breast cancer. The natural history of this disease was changed dramatically by the introduction of these combined modality therapies. Five-year disease-free survival rates of 35%-70% are commonly reported, and about 25%-40% of patients will survive beyond 10 years without recurrence. In summary, multidisciplinary therapy that includes primary chemotherapy provides appropriate local control and the possibility of breast conservation therapy; it increases surgical resectability and survival rates in patients with locally advanced breast cancer. The role of new innovative therapeutic strategies such as high-dose chemotherapy, with hematopoietic stem cell rescue, new cytotoxic agents and higher dose-intensity therapy is currently under evaluation in patients with locally advanced breast cancer.