Division of Medical Oncology, McGill University Health Center, McGill University, Montreal, Canada.
Breast Cancer Res Treat. 2013 Jun;139(2):603-6. doi: 10.1007/s10549-013-2561-7. Epub 2013 May 17.
Improvements in adjuvant therapy have led to a sustained fall in recurrences after early breast cancer. The differential reduction in local and systemic recurrences is poorly understood. This study aimed to explore changes in the distribution of loco-regional and distant recurrences in clinical trials reported over the last 20 years. We also aimed to determine the relative impact of adjuvant chemotherapy and endocrine therapy. MEDLINE search for adjuvant, phase III randomized breast cancer clinical studies between January 1990 and March 2011 was performed. Neoadjuvant, single agent biologics and studies that did not report the proportion of loco-regional and distant recurrences were excluded. The change in the frequency of recurrences was assessed as the nonparametric correlation between the number of loco-regional recurrences as a proportion of all recurrences and time. Studies were weighted by sample size. The differential effect of chemotherapy and endocrine therapy was also assessed. Fifty-three randomized clinical trials with a total of 86,598 patients were included in the analysis. Between 1990 and 2011, the proportion of loco-regional recurrences has decreased from approximately 30 to 15 % (Spearman's ρ = -0.40, p < 0.001). There was no interaction between type of surgery (mastectomy vs. lumpectomy), administration of adjuvant radiation therapy and menopausal status and the correlation of loco-regional recurrences and time. Chemotherapy regimen showed a larger negative correlation compared with endocrine therapy ( ρ = 0.49 vs. ρ = 0.24). Advances in treatment of early breast cancer have differentially reduced the proportion of loco-regional recurrences compared with distant recurrences. In recent trials, loco-regional recurrences account for less than 10-15 % of all recurrences. These falling event rates may affect patient care, especially when deciding on treatments influencing loco-regional control. This change may also impact on the design of clinical trials assessing loco-regional therapy such as surgery and/or local radiation therapy.
辅助治疗的改进导致早期乳腺癌复发率持续下降。局部和全身复发的差异减少机制尚不清楚。本研究旨在探讨过去 20 年报告的临床试验中局部和远处复发分布的变化。我们还旨在确定辅助化疗和内分泌治疗的相对影响。对 1990 年 1 月至 2011 年 3 月期间发表的辅助性、III 期随机乳腺癌临床研究进行了 MEDLINE 检索。排除新辅助、单一生物制剂和未报告局部和远处复发比例的研究。通过局部复发的数量与所有复发的比例与时间之间的非参数相关性来评估复发频率的变化。研究的权重为样本量。还评估了化疗和内分泌治疗的差异影响。共纳入 53 项随机临床试验，总计 86598 例患者。1990 年至 2011 年间，局部复发的比例从大约 30%降至 15%（Spearman's ρ = -0.40，p < 0.001）。手术类型（乳房切除术与乳房肿块切除术）、辅助放疗和绝经状态与局部复发和时间的相关性之间无交互作用。与内分泌治疗相比，化疗方案显示出更大的负相关性（ρ=0.49 比 ρ=0.24）。早期乳腺癌治疗的进展使局部复发的比例与远处复发的比例差异缩小。在最近的试验中，局部复发占所有复发的比例不到 10-15%。这些下降的事件发生率可能会影响患者的治疗，尤其是在决定影响局部控制的治疗方法时。这种变化也可能影响评估局部治疗（如手术和/或局部放疗）的临床试验的设计。
