Timing of postoperative chemotherapy

A retrospective, observational, single-institution study of patients with early-stage breast cancer who were diagnosed between 1997 and 2011 revealed that delays in initiation of adjuvant chemotherapy adversely affected survival outcomes.[35][Level of evidence C1]

A retrospective, observational, single-institution study of patients with early-stage breast cancer who were diagnosed between 1997 and 2011 revealed that delays in initiation of adjuvant chemotherapy adversely affected survival outcomes.[35][Level of evidence C1]

Initiation of chemotherapy 61 days or more after surgery was associated with adverse outcomes among patients with stage II breast cancer (distant RFS [DRFS]: HR, 1.20; 95% CI, 1.02–1.43) and stage III breast cancer (OS: HR, 1.76; 95% CI, 1.26–2.46; RFS: HR, 1.34; 95% CI, 1.01–1.76; and DRFS: HR, 1.36; 95% CI, 1.02–1.80).

A retrospective, observational, single-institution study of patients with early-stage breast cancer who were diagnosed between 1997 and 2011 revealed that delays in initiation of adjuvant chemotherapy adversely affected survival outcomes.[35][Level of evidence C1]

Patients with triple-negative breast cancer (TNBC) and those with HER2-positive tumors treated with trastuzumab who started chemotherapy 61 days or more after surgery had worse survival (TNBC: HR, 1.54; 95% CI, 1.09–2.18; HER2-positive: HR, 3.09; 95% CI, 1.49–6.39) than did those who initiated treatment in the first 30 days after surgery.

A retrospective, observational, single-institution study of patients with early-stage breast cancer who were diagnosed between 1997 and 2011 revealed that delays in initiation of adjuvant chemotherapy adversely affected survival outcomes.[35][Level of evidence C1]

Because of the weaknesses and limitations of this study design, the optimal time to initiate adjuvant chemotherapy remains uncertain.

A population-based study from California included 24,843 patients and found that delays in initiating adjuvant chemotherapy of 90 days or less had no impact on OS, but found a substantial effect for delays over 90 days (HR, 1.27; 95% CI, 1.05–1.53), particularly among patients with TNBC.[36][Level of evidence C1]

Multiple other studies have examined the effect of treatment delays of 90 days or less and have reported inconsistent results, with the possible exception of patients with TNBC.[36]