Impact of progression during neoadjuvant chemotherapy on surgical management of breast cancer

Background: Although neoadjuvant chemotherapy (NCT) is standard therapy for locally advanced breast cancer, it remains controversial for early-stage disease due to concerns that disease progression may make breast-conservation therapy (BCT), or even operability, impossible. The goal of this study was to determine the impact of disease progression during NCT on surgical management. Methods: We reviewed clinicopathological data on patients who received NCT for stage I-III breast cancer from 1994 to 2007. Chemotherapy regimens were anthracycline- and/or taxane-based as determined by the treating medical oncologist. Results: Of 1,928 patients who received NCT, 1,762 (91%) had a partial or complete response, 107 (6%) had stable disease (SD), and 59 (3%) progressed (PD) while receiving at least one regimen. Of the patients with progressive disease, 40 (68%) patients underwent mastectomy, 12 (20%) underwent BCT, and 7 (12%) did not undergo surgery. In patients who underwent mastectomy, only three (8%) were BCT candidates before progression. Overall, disease progression changed the operative plan in 11 (0.5%) patients: 3 developed distant metastasis, 2 developed clinical lymphadenopathy, 3 required mastectomy instead of BCT, 2 became inoperable, and 1 required flap closure. Conclusions: Disease progression while receiving NCT is infrequent (3%), but early identification may allow for change to other, potentially beneficial, therapeutic interventions. Patients with breast cancer who receive NCT should be evaluated frequently for response to therapy. Overall, progression during NCT changes the surgical management in a small proportion of patients.