Purpose
We sought to determine outcomes for patients with metastatic breast cancer (MBC) with no evidence of disease (NED) after treatment and to identify factors predictive of outcome once NED status was attained.
Methods
We reviewed 570 patients with MBC consecutively treated between January 2003 through December 2005. Ninety patients (16%) attained NED, as defined by a complete metabolic response by positron emission tomography or sclerotic healing of bone metastases on computed tomography or magnetic resonance imaging. Median follow-up for patients attaining NED was 100 months (range, 14–134 months).
Results
The 3- and 5-year overall survival (OS) rates for the entire group were 44% and 24%, respectively, compared to 96% and 78% for those attaining NED. Using a landmark analysis, NED status was significantly associated with survival at 2 years (P<0.001, HR 0.23, 95% CI 0.16-0.34) and 3 years (P<0.001, HR 0.20, 95% CI 0.14-0.30). From the time of NED, the median survival was 102 months (range, 14-134) with a 5-year OS and progression free survival (PFS) of 77% and 40%, respectively. On multivariate analysis, HER2+ was significantly associated with OS (vs. ER+, P=0.02, HR 0.44, 95% CI 0.21-0.90), and trastuzumab use was significantly associated with PFS (P=0.007, HR 0.48, 95% CI 0.28-0.82). Thirty-one patients (34%) with NED remained in remission at last follow-up.
Conclusions
MBC patients who attain NED status have a significantly prolonged survival with a durable response to therapy. Ultimately, this study provides essential outcomes data for clinicians and patients living with MBC.