Efficacy of Single‐Agent Chemotherapy for Patients with Advanced Invasive Lobular Carcinoma: A Pooled Analysis from Three Clinical Trials

Abstract

This article reports on the efficacy of eribulin for the treatment of advanced invasive lobular carcinoma compared with invasive ductal carcinoma.

Abstract

Background.

Data on the efficacy of chemotherapy regimens in patients with advanced invasive lobular carcinoma (ILC) of the breast are limited. We investigated the efficacy of single‐agent eribulin for the treatment of advanced ILC when compared with invasive ductal carcinoma (IDC).

Patients and Methods.

Results from the eribulin arms of two phase III studies (305 [EMBRACE] and 301) and a single‐arm, phase II study were pooled. The studies involved patients with metastatic breast cancer who had previously received treatment with an anthracycline and a taxane. In all three studies, the dose of eribulin mesylate was 1.4 mg/m ² given on days 1 and 8 of a 21‐day cycle. Overall survival (OS), progression‐free survival (PFS), and response rates in patients with ILC were assessed and compared with data from patients with IDC.

Results.

In total, 1,152 patients were included in this analysis (118 patients with ILC and 1,034 patients with IDC). Median OS was similar in patients with ILC and IDC (13.4 vs. 13.5 months; hazard ratio [HR], 1.10; 95% confidence interval [CI], 0.87–1.38); as was median PFS (4.1 vs. 3.6 months; HR, 0.91; 95% CI, 0.72–1.14). There were no major differences in response rates between the two groups.

Conclusion.

This retrospective analysis suggests that eribulin demonstrates similar efficacy in patients with ILC and IDC with metastatic disease who have previously received an anthracycline and a taxane.

Implications for Practice.

Data on the efficacy of chemotherapy regimens in patients with advanced invasive lobular carcinoma (ILC) of the breast are limited. This pooled retrospective analysis of three clinical studies demonstrates that the magnitude of benefit of eribulin in the metastatic setting did not differ between patients with ILC versus invasive ductal carcinoma (IDC), even when restricting for patients with estrogen receptor‐positive/HER2‐negative IDC.

Translated abstract

摘要

背景。 关于化疗方案对晚期乳腺浸润性小叶癌 (ILC) 患者的有效性的数据十分有限。我们研究了单药艾日布林治疗晚期 ILC 对比浸润性导管癌 (IDC) 的有效性。

患者和方法。 我们对来自两项 III 期研究 [305 (EMBRACE)和 301] 和一项单组 II 期研究的艾日布林组结果进行了汇总。这些研究涉及既往曾接受蒽环霉素和紫杉烷治疗的转移性乳腺癌患者。在所有三项研究中，在一个为期 21 天的周期中，甲磺酸艾日布林在第 1 天和第 8 天的剂量为 1.4 mg/m ²。我们对 ILC 患者的总生存期 (OS)、无进展生存期 (PFS) 以及反应率进行评估，并将它们与 IDC 患者的数据进行对比。

结果。 本分析中共包含 1 152 名患者(118 名 ILC 患者和 1 034 名 IDC 患者)。ILC 患者与 IDC 患者中的中位 OS 相似 [13.4 个月vs. 13.5 个月；风险比 (HR)，1.10；95% 置信区间 (CI)，0.87–1.38]；中位 PFS 也是如此(4.1 个月vs. 3.6 个月；HR，0.91；95% CI，0.72–1.14)。两组之间的反应率没有重大差异。

结论。 本回顾性分析表明，艾日布林在既往曾接受蒽环霉素和紫杉烷治疗且患有转移性疾病的 ILC 患者和 IDC 患者中的有效性相似。

实践意义:关于化疗方案对晚期乳腺浸润性小叶癌 (ILC) 患者的有效性的数据十分有限。本次关于三项临床研究的汇总式回顾性分析证明，即使限制在雌激素受体‐阳性/HER2‐阴性 IDC 患者时，艾日布林在转移性疾病中的有益程度在 ILC 患者与浸润性导管癌 (IDC) 患者之间也没有任何差别。