Factors associated with prolonged overall survival in patients with postmenopausal estrogen receptor-positive advanced breast cancer using real-world data: a follow-up analysis of the JBCRG-C06 Safari study

Hidetoshi Kawaguchi,Eriko Tokunaga,Keisei Anan,Masao Hattori ,Tomomi Fujisawa,Yoshiaki Ito ,Yoshio Miki ,Norikazu Masuda,Daisuke Yotsumoto,Shoichiro Ohtani,Yoshie Hasegawa,Toshimi Takano,Yutaka Yamamoto,Shigehira Saji,Masakazu Toi,Nobuaki Sato,Hiroko Yamashita,Takahiro Nakayama,Toshinari Yamashita,Satoshi Morita,Seigo Nakamura,Kenjiro Aogi,Shinji Ohno

doi:10.1007/s12282-019-01029-3

Abstract

BackgroundAssessing survival risk is important for discussing treatment options with estrogen receptor-positive (ER+) advanced breast cancer (ABC) patients. However, there are few reports from large-scale databases on the survival risk factors in ER+ ABC. The Safari study (UMIN000015168) was a retrospective, multicenter cohort study involving 1072 Japanese patients receiving fulvestrant 500 mg mostly as a second- or later-line endocrine therapy for ER+ ABC. The follow-up data after the Safari study were examined, focusing on any relationship between clinicopathological factors and overall survival (OS) in ER+ ABC patients.MethodsOS in patients with ER+ ABC was analyzed by univariate and multivariate analyses with a Cox proportional hazards model in this study.ResultsA total of 1031 cases were evaluable for OS analysis. Multivariate analysis showed that younger age (< 60 years), longer time from ABC diagnosis to fulvestrant use (≥ 3 years), no prior palliative chemotherapy before fulvestrant use, and progesterone receptor (PgR) negativity (PgR−) were significantly correlated with prolonged OS (median 7.0 years). For cases with histological or nuclear grade data, lower histological or nuclear grades were also correlated with longer OS. In recurrent metastatic cases, long disease-free interval (DFI) was not correlated with longer OS.ConclusionsIn ER+ ABC patients whose treatment history included fulvestrant, younger age, longer time from ABC diagnosis to fulvestrant use, no prior palliative chemotherapy use, PgR−, and lower histological or nuclear grade correlated positively with prolonged OS.

Highlights

Most breast cancer patients who are diagnosed at an early stage have a good clinical outcome [1]
Patients were followed according to the guidelines of the Japan Breast Cancer Society and the National Comprehensive Cancer Network (NCCN) Guidelines for Invasive Breast Cancer (Version 4.2018) [20], which is the standard treatment in Japan
1031 (96.2%) patients with ER+ advanced breast cancer (ABC) were eligible for the overall survival (OS) analysis

Summary

Introduction

Most breast cancer patients who are diagnosed at an early stage have a good clinical outcome [1]. Nearly 30% of patients newly diagnosed with early-stage breast cancer will later develop recurrent metastatic cancer [2], for whom the 5-year survival rate is approximately 20% [3]. Assessing survival risk is important for discussing treatment options with estrogen receptor-positive (ER+) advanced breast cancer (ABC) patients. Multivariate analysis showed that younger age (< 60 years), longer time from ABC diagnosis to fulvestrant use (≥ 3 years), no prior palliative chemotherapy before fulvestrant use, and progesterone receptor (PgR) negativity (PgR−) were significantly correlated with prolonged OS (median 7.0 years). Conclusions In ER+ ABC patients whose treatment history included fulvestrant, younger age, longer time from ABC diagnosis to fulvestrant use, no prior palliative chemotherapy use, PgR−, and lower histological or nuclear grade correlated positively with prolonged OS

Methods

Results

Conclusion