P2-16-05: Delay of Adjuvant Chemotherapy after Elective Mastectomy and Immediate Reconstruction in Breast Conservation Candidates: A Matched-Pair Analysis.

Abstract

Abstract Background: To analyze factors that influence the timing of adjuvant chemotherapy in patients who are candidates for breast conservation therapy (BCT) but elect mastectomy with immediate reconstruction (M-IR). Methods: Using data from the University of Louisville Cancer Registry, we identified 35 consecutively-treated patients with stage I or II breast cancer between 2004 and 2009 who underwent M-IR and adjuvant chemotherapy. These were matched for age and AJCC stage to 35 controls who underwent BCT and adjuvant chemotherapy. We examined the timing of initiation of chemotherapy from the date of surgery and assessed the probability of therapeutic delay using univariate logistic regression and McNemar's test for matched pairs. Results: For the 70 patients included in this study, the median age was 46y (range: 30–65y), and the distribution for stage I, IIA and IIB was 22.9%, 65.7% and 11.4%, respectively. The two groups were well balanced in terms of race, rural/urban status, smoking, diabetes, insurance coverage, and histology. The median time to initiation of adjuvant chemotherapy was 38 days (range: 25–103 days) for BCT and 55 days (range: 30–165 days) for M-IR. Patients undergoing M-IR were more likely to experience any delay (> 45 days; 74.3% vs. 25.7%, p < 0.001) and/or significant delay (>90 days; 20.0% vs. 2.9%, p < 0.001) than those choosing BCT. On univariate logistic regression analysis, the extent of surgery had a major impact on the likelihood of any delay in chemotherapy (OR= 8.35, 95% C.I. = 2.86−24.3, p <0.001). None of the other aforementioned factors predicted for delay. Conclusion: The use of elective mastectomy with immediate reconstruction in breast conservation candidates independently predicts for delay in initiation of adjuvant chemotherapy. Further study is needed to qualify the underlying causes of and ultimate clinical significance of these delays. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-16-05.