Locally advanced breast cancer.

Abstract

Over the past 20 years, the prognosis for women diagnosed with locally advanced breast cancer (LABC; clinical stages IIB through IIIB) has improved significantly with recognition of the efficacy of multimodal therapy for reducing both local and distant recurrences, even in patients with inflammatory breast cancer (IBC). Most patients will respond to induction, or neoadjuvant, chemotherapy (NAC) with an anthracycline-based regimen, enabling many patients with large but operable tumors to undergo breast-conserving surgery (BCS) and enabling resection in most patients with inoperable disease. However, only a small percentage of patients achieve a pathologic complete response (CR) with this approach. Long-term disease-free survival (DFS) and overall survival (OS) correlate with the extent of residual disease in the breast and axillary nodes following NAC. The addition of paclitaxel or docetaxel, either in combination with an anthracycline or as a separate regimen administered before or after anthracycline-based therapy, increases clinical and pathologic response rates and may improve DFS. With the possible exception of patients with IBC, BCS does not compromise outcome. Partial mastectomy should be accompanied by standard nodal dissection in patients with clinically or radiographically positive axillae; in patients with negative axillae, sentinel lymph node (SLN) sampling, with subsequent axillary dissection reserved for patients with involved nodes, may reduce postoperative morbidity. Patients who received only anthracycline-based NAC who are found to have significant residual disease in the breast or involved axillary nodes at surgery should receive adjuvant chemotherapy with paclitaxel. Postoperative radiation to the residual breast or chest wall and regional nodal areas reduces locoregional recurrences, but its impact on OS remains controversial. Adjuvant hormonal therapy with tamoxifen improves DFS and OS in patients with hormone receptor (HR)-positive tumors, and ovarian ablation should be considered in premenopausal patients with HR-positive tumors and multiple involved nodes or stage IIIB disease. Neoadjuvant hormonal therapy with either tamoxifen or an aromatase inhibitor may benefit frail or elderly patients with HR-positive tumors for whom chemotherapy is not an option. No advantage has been demonstrated for high-dose chemotherapy requiring hematopoietic stem-cell support as either NAC or adjuvant therapy in LABC. Newer treatment approaches, including trastuzumab (Herceptin, Genentech, Inc., South San Francisco, CA), in patients with Her-2-overexpressing tumors or other biologic agents, do not have a proven role in the management of LABC at this time.