Impact of Breast Reconstruction on Time to Definitive Surgical Treatment, Adjuvant Therapy, and Breast Cancer Outcomes.

Background: Delays in surgery and adjuvant treatment for breast cancer are associated with decreased survival. However, the time between diagnosis and surgery is rising, partly attributed to the added complexity of immediate breast reconstruction (IBR). We sought to investigate time to treatment and survival outcomes in breast cancer patients undergoing IBR.

Methods: We performed a retrospective review of 2004-2014 California Cancer Registry data for stage 0-III breast cancer patients undergoing mastectomy. Time to surgery, adjuvant systemic therapy and radiation therapy, propensity score, and covariate-adjusted overall mortality hazard ratios (HRs) were assessed by IBR status.

Results: Of 56,782 patients, 13,738 (24.2%) underwent IBR, with a median follow-up of 68.8 months. Median time between diagnosis and surgery was increased for patients undergoing IBR compared with those without {49 days (interquartile range [IQR] 34-73) vs. 35 days (IQR 21-56), p < 0.001}. IBR did not affect the interval from surgery to adjuvant chemotherapy or radiation, but prolonged time to endocrine therapy by 5 days (p = 0.014). Significantly lower survival was observed when time to surgery exceeded 120 days (vs. 0-30 days; HR 1.14 [1.02-1.28], p = 0.023), and improved survival with IBR (vs. without; HR 0.67 [0.61-0.74], p < 0.001). The benefit associated with reconstruction persisted for all age groups except age 80 + years, while surgical delay > 120 days demonstrated significantly lower survival in women < 60 years of age.

Conclusions: While IBR delays time to definitive surgery, its use did not substantially affect time to adjuvant treatment or survival outcomes. Further research is ongoing to mitigate the effects of potential selection bias in favor of IBR.