Efficacy of fulvestrant in the treatment of postmenopausal women with endocrine-resistant advanced breast cancer in routine clinical practice

Clin Transl Oncol. 2018 Jul;20(7):862-869. doi: 10.1007/s12094-017-1797-9. Epub 2017 Nov 24.

Abstract

Introduction: This study aimed to describe the efficacy of fulvestrant 500 mg in postmenopausal women with estrogen receptor (ER)-positive advanced/metastatic breast cancer who had disease progression after receiving anti-estrogen therapy in clinical practice, getting real-world data.

Materials and methods: Multicenter, retrospective, observational study conducted in Spain. Postmenopausal women with locally advanced/metastatic ER-positive breast cancer who received treatment with fulvestrant 500 mg after progression with a previous anti-estrogen therapy were eligible. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), clinical benefit rate (CBR), duration of clinical benefit (DoCB), and safety profile.

Results: A total of 263 women were evaluated (median age, 65.8 years). At a median follow-up of 21.5 months, median PFS and OS were 10.6 and 43.2 months, respectively. PFS according to 1st, 2nd, 3rd, and ≥ 4th lines were 11.5, 10.6, 9.9, and 8.5 months, respectively (p = 0.0245). PFS in patients with visceral involvement was 10 months vs 10.6 months in patients without visceral involvement (p = 0.6604), 9.6 months in patients with high Ki67 vs 10 months in patients with low Ki67 (p = 0.7224), and 10.2 months in HER2+ patients vs 10.3 months in HER2- patients (p = 0.6809). The CBR was 56.5% and the DoCB was 18.4 months. The most frequently adverse events were injection site pain (10.3%) and musculoskeletal disorders (7.6%).

Conclusions: Fulvestrant 500 mg administered in clinical practice was shown to be effective (PFS, 10.6 months; CBR, 56.5%) and well tolerated, in accordance with previous trials.

Keywords: Fulvestrant; Hormone receptor-positive advanced breast cancer; Metastatic breast cancer; Postmenopausal women.

Publication types

  • Observational Study

MeSH terms

  • Aged
  • Antineoplastic Agents, Hormonal / therapeutic use
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Carcinoma, Ductal, Breast / drug therapy*
  • Carcinoma, Ductal, Breast / metabolism
  • Carcinoma, Ductal, Breast / secondary
  • Carcinoma, Lobular / drug therapy*
  • Carcinoma, Lobular / metabolism
  • Carcinoma, Lobular / secondary
  • Drug Resistance, Neoplasm*
  • Estradiol / analogs & derivatives*
  • Estradiol / therapeutic use
  • Female
  • Follow-Up Studies
  • Fulvestrant
  • Humans
  • Lymphatic Metastasis
  • Middle Aged
  • Postmenopause*
  • Prognosis
  • Receptor, ErbB-2 / metabolism
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / metabolism
  • Retrospective Studies

Substances

  • Antineoplastic Agents, Hormonal
  • Receptors, Estrogen
  • Receptors, Progesterone
  • Fulvestrant
  • Estradiol
  • Receptor, ErbB-2