This study 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 outcomes once the status of NED was attained.

This study reviewed 570 patients with MBC who were consecutively treated between January 2003 and December 2005. Ninety patients (16%) attained NED, which was defined as a complete metabolic response on positron emission tomography or sclerotic healing of bone metastases on computed tomography or magnetic resonance imaging. The median follow-up for patients attaining NED was 100 months (range, 14-134 months).

The 3- and 5-year overall survival (OS) rates were 44% and 24%, respectively, for the entire group and 96% and 78%, respectively, for those attaining NED. According to a landmark analysis, NED status was significantly associated with survival at 2 (P < .001; hazard ratio [HR], 0.23; 95% confidence interval [CI], 0.16-0.34) and 3 years (P < .001; HR, 0.20; 95% CI, 0.14-0.30). From the time of NED, the median survival was 102 months (range, 14-134 months) with 5-year OS and progression-free survival (PFS) rates of 77% and 40%, respectively. According to a multivariate analysis, human epidermal growth factor receptor 2 positivity was significantly associated with OS in comparison with estrogen receptor positivity (P = .02; HR, 0.44; 95% CI, 0.21-0.90), and trastuzumab use was significantly associated with PFS (P = .007; HR, 0.48; 95% CI, 0.28-0.82). Thirty-one patients (34%) with NED remained in remission at the last follow-up.

MBC patients who attain the status of NED have significantly prolonged survival with a durable response to therapy. Ultimately, this study provides essential outcome data for clinicians and patients living with MBC.