Department of Oncology, Ospedale Civile di Sanremo, Via G. Borea n. 56, 18038, Sanremo, Imperia, Italy.
Int J Clin Oncol. 2019 Mar;24(3):231-240. doi: 10.1007/s10147-019-01405-1. Epub 2019 Feb 4.
Early tumor shrinkage (ETS) is a response-related endpoint of clinical trials of chemotherapy (CHT) of patients with metastatic colorectal cancer (mCRC). It identifies a dimensional reduction of tumor size by at least 20-30% after 6-8 weeks of CHT.
A literature search of randomized trials of systemic treatment including CHT with or without antiangiogenics or anti-EGFR inhibitors in patients with mCRC has been conducted, and studies reporting the results of the relationship of ETS with overall survival (OS) and progression-free survival (PFS) were selected.
Twelve trials, including 3117 patients, have been included; all data were retrospective and only 72% of the enrolled patients have been evaluated for ETS. Two meta-analyses, each including 20 study cohorts from the selected 12 trials, reported a strong relationship of ETS with OS (HR 0.62; CIs 0.55-0.69) and of ETS with PFS (HR 0.66; CIs 0.60-0.73). However, both meta-analyses displayed a high level of heterogeneity. Among nine possible moderators, three variables (median age, surgery of metastases, and publication year) were able to explain at least a part of this heterogeneity.
ETS is a simple and interesting intermediate endpoint for clinical practice and future trials of medical treatments of patients with mCRC, but a large prospective analysis and validation are mandatory.
早期肿瘤退缩（ETS）是转移性结直肠癌（mCRC）患者化疗（CHT）临床试验的一种与疗效相关的终点指标。它指的是在 CHT 治疗 6-8 周后肿瘤大小至少减少 20-30%。
对包括 CHT 联合或不联合抗血管生成药物或抗 EGFR 抑制剂在内的系统治疗的随机试验进行了文献检索，并选择了报告 ETS 与总生存期（OS）和无进展生存期（PFS）关系的研究。
共纳入 12 项试验，包括 3117 例患者；所有数据均为回顾性，只有 72%的入组患者评估了 ETS。两项荟萃分析，每项分析均包括 12 项试验中的 20 个研究队列，报告了 ETS 与 OS（HR 0.62；95%CI 0.55-0.69）和 ETS 与 PFS（HR 0.66；95%CI 0.60-0.73）的强相关性。然而，这两项荟萃分析均显示出高度的异质性。在九个可能的调节因素中，三个变量（中位年龄、转移灶手术和发表年份）能够解释部分异质性。
ETS 是 mCRC 患者临床实践和未来药物治疗试验的一种简单而有趣的中间终点指标，但需要进行大型前瞻性分析和验证。
