Time to Completion of Breast Cancer Treatment and Survival

Breast cancer treatment delays are common. This study was designed to examine the association between the time interval from time of diagnosis to completion of all acute breast cancer treatment modalities (surgery, chemotherapy, and radiation therapy) and survival.

A retrospective analysis was performed utilizing data from the National Cancer Database (NCDB) to determine an association between the duration of time from diagnosis to completing all acute breast cancer treatment (surgery, chemotherapy, and radiation therapy) and survival. Secondary survival analysis evaluated whether delay in treatment completion varied by differences in tumor receptor status.

We analyzed 2010 NCDB data of stage I-III breast cancer patients. A subset of 28,284 patients received all three modalities (surgery, chemotherapy, and radiation) as their acute treatment. Median follow-up was 5.8 years. Cox proportional hazards model identified a cut-off showing the risk of delaying completion of all treatment beyond 38 weeks was associated with a decrease in overall survival (hazard ratio [HR] 1.21). This decrease in survival was significant regardless of the major tumor receptor status: triple-negative (HR 1.188, 95% confidence interval [CI] 1.06-1.34), estrogen receptor (ER)+/progesterone receptor (PR)+/human epidermal growth factor receptor 2 (HER2)- (HR 1.22, 95% CI 1.09-1.36), ER-/PR-/HER2+ (HR 1.29, 95% CI 1.004-1.67), and ER+/PR+/HER2+ (HR 1.32, 95% CI 1.01-1.72).

Efforts to improve the efficiency of multimodality breast cancer treatment and reduce treatment delays should be a priority to optimize breast cancer patient outcomes.