3917 - Impact of delayed neoadjuvant systemic chemotherapy on survival among breast cancer patients

Background

Delays in the initiation of therapy among patients with early stage and locally advanced breast cancer (BC), can negatively impact survival. Patients treated with neoadjuvant systemic chemotherapy (NSC) usually display tumors with high-risk features. Considering these high-risk characteristics, and the evidence supporting adverse outcomes associated with delays in adjuvant chemotherapy initiation, we sought to determine whether time to NSC is associated with survival outcomes.

Methods

We identified patients diagnosed with invasive primary BC (stage I–III)be tween January 1995-December 2015. All patients were treated with NSC at MD Anderson Cancer Center. Patients were categorized according to their time from BC diagnosis to NSC (in days) into one of the three subgroups: 0-30, 31–60, and 61 days. Primary endpoint was overall survival (OS). Descriptive statistics and Cox Proportional Hazard models were used.

Results

A total of5,137 patients were included. Median follow-up was 6.9 years. The 5-year OS estimates according to time to NSC were 87%, 85% and 83% in patients who received NSC within 0-30, 31-60 and 61 days after diagnosis, respectively (P = 0.006). In multivariable analysis, compared to time to NSC of 0-30 days, delayed NSC 61 days was associated with an increased risk of death (31-60 days HR = 1.05 [95%CI 0.92-1.19]; >61 days, HR = 1.28 [95%CI 1.06-1.54]). In stratified analyses, the association between delay in NSC initiation and increased risk of death was statistically significant for patients with stage I, II (31-60 days: HR = 1.22 [95%CI 1.02-1.47]; 61 days, HR = 1.41 [95%CI 1.07-1.86]) BC and among patients with HER2+ tumors (61 days, HR=1.86 [95%CI 1.21-2.86]).

Conclusions

A delay in NSC initiation of more than 61 days after BC diagnosis is associated with an increased risk of death. Early initiation of NSC should be a priority; multidisciplinary teams must focus in coordination of care and patient-centered timely treatment planning and delivery.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

MD Anderson Cancer Center, Susan G Komen.

Disclosure

All authors have declared no conflicts of interest.