AbstractBackgroundRisk‐stratified follow‐up guidelines that account for the absolute risk and timing of recurrence may improve the quality and efficiency of breast cancer follow‐up. The objective of this study was to assess the relationship of anatomic stage and receptor status with timing of the first recurrence for patients with local‐regional breast cancer and generate risk‐stratified follow‐up recommendations.MethodsThe authors conducted a secondary analysis of 8007 patients with stage I–III breast cancer who enrolled in nine Alliance legacy clinical trials from 1997 to 2013 (ClinicalTrials.gov identifier NCT02171078). Patients who received standard‐of‐care therapy were included. Patients who were missing stage or receptor status were excluded. The primary outcome was days from the earliest treatment start date to the date of first recurrence. The primary explanatory variable was anatomic stage. The analysis was stratified by receptor type. Cox proportional‐hazards regression models produced cumulative probabilities of recurrence. A dynamic programming algorithm approach was used to optimize the timing of follow‐up intervals based on the timing of recurrence events.ResultsThe time to first recurrence varied significantly between receptor types (p < .0001). Within each receptor type, stage influenced the time to recurrence (p < .0001). The risk of recurrence was highest and occurred earliest for estrogen receptor (ER)‐negative/progesterone receptor (PR)‐negative/Her2neu‐negative tumors (stage III; 5‐year probability of recurrence, 45.5%). The risk of recurrence was lower for ER‐positive/PR‐positive/Her2neu‐positive tumors (stage III; 5‐year probability of recurrence, 15.3%), with recurrences distributed over time. Model‐generated follow‐up recommendations by stage and receptor type were created.ConclusionsThis study supports considering both anatomic stage and receptor status in follow‐up recommendations. The implementation of risk‐stratified guidelines based on these data has the potential to improve the quality and efficiency of follow‐up.
Local/Regional Recurrence Rates After Breast-Conserving Therapy in Patients Enrolled in Legacy Trials of the Alliance for Clinical Trials in Oncology (AFT-01)
Objective: We sought to evaluate local/regional recurrence rates after breast-conserving surgery in a cohort of patients enrolled in legacy trials of the Alliance for Clinical Trials in Oncology and to evaluate variation in recurrence rates by receptor subtype. Background: Multiple randomized controlled trials have demonstrated equivalent survival between breast conservation and mastectomy, albeit with higher local/regional recurrence rates after breast conservation. However, absolute rates of local/regional recurrence have been declining with multi-modality treatment. Methods: Data from 5 Alliance for Clinical Trials in Oncology legacy trials that enrolled women diagnosed with breast cancer between 1997 and 2010 were included. Women who underwent breast-conserving surgery and standard systemic therapies (n=4,404) were included. Five-year rates of local/regional recurrence were estimated from Kaplan-Meier curves. Patients were censored at the time of distant recurrence (if recorded as the first recurrence), death, or last follow-up. Multivariable Cox proportional hazards models were used to identify factors associated with time to local/regional recurrence, including patient age, tumor size, lymph node status, and receptor subtype. Results: Overall 5-year recurrence was 4.6% (95% CI=4.0-5.4%). Five-year recurrence rates were lowest in those with ER+ or PR+ tumors (Her2+ 3.4% [95% CI 2.0-5.7%], Her2- 4.0% [95% CI 3.2-4.9%]) and highest in the triple-negative subtype (7.1% [95% CI 5.4-9.3%]). On multivariable analysis, increasing nodal involvement and triple-negative subtype were positively associated with recurrence (P<0.0001). Conclusions: Rates of local/regional recurrence after breast conservation in women with breast cancer enrolled in legacy trials of the Alliance for Clinical Trials in Oncology are significantly lower than historic estimates. This data can better inform patient discussions and surgical decision-making.