BRCA status, treatment patterns and outcomes in HER2- advanced breast cancer (ABC): A multi-country real-world study

Date 03 May 2019
Event ESMO Breast Cancer 2019
Session Poster lunch
Topics Aetiology, Epidemiology, Screening and Prevention
Breast Cancer
Hereditary Syndromes
Presenter Alexander Niyazov
Citation Annals of Oncology (2019) 30 (suppl_3): iii47-iii64. 10.1093/annonc/mdz100
Authors A. Niyazov1, R.G..W. Quek2, K. Lewis3, J. Kemp3, A. Rider4
  • 1Health Economics & Outcomes Research, Pfizer, 10017 - New York/US
  • 2Health Economics & Outcomes Research, Pfizer Inc., 94105 - San Francisco/US
  • 3Oncology, Adelphi Real World, Cheshire/GB
  • 4Oncology, Adelphi Real World, SK10 5JB - Bollington/GB

Abstract

Background

BRCA testing rates, treatment patterns and outcomes were compared based on BRCA mutation status in HER2- adult women with ABC.

Methods

Oncologists extracted data from patient charts in adult women with HER2- ABC across the US and France, Germany, Italy, Spain and the United Kingdom (EU5) via the Adelphi Advanced Breast Cancer Disease Specific Program. Data drawn from 2015 and 2017 were merged across common variables. Patients were categorized into three mutually exclusive cohorts; BRCA mutations (BRCAm), wild type (BRCAwt), and unknown status (BRCAunk). Treatments received and 1st line duration of therapy was compared between BRCAm and BRCAwt using Fisher exact, Mann-Whitney tests, and t-tests.

Results

The study included 6,161 adult women with HER2- ABC (4,611 hormone receptor positive [HR+/HER2-], 1,415 triple negative breast cancer [TNBC], 135 unknown hormone status). Overall, 28% of patients received ≥1 BRCA test at any point in their lifetime (23% HR+/HER2-, 41% TNBC). 235/6,161 (4%) patients were identified as BRCAm, 1,025/6,161 (17%) as BRCAwt, and 4,901/6,161 (80%) as BRCAunk. Within the HR+/HER2- cohort, patients with BRCAm were more likely to receive 1st line chemotherapy compared to BRCAwt (65% vs 49%; P = 0.005) and less likely to receive endocrine +/- targeted therapies (33% vs 49%; P = 0.003). TNBC treatments consisted primarily of chemotherapy and were similar between BRCAm vs. BRCAwt, (89% vs. 91%; P = 0.545). Mean duration among patients who completed 1st line treatment was numerically shorter for patients with BRCAm [Table].

Table: 161P

1st line duration of therapy (mean months [SD]) based on BRCA status

BRCAm (n = 34)BRCAwt (n = 282)P value
HR+/HER2-7.8[10.0]11.4 [5.5]0.648
TNBC6.4 [6.1]5.0 [2.9]0.933
HER2-a6.6 [7.0]9.0 [13.4]0.408
a

Includes HR+, TNBC and HR unknown patients.

Conclusions

In this study of adult women with HER2- ABC, low BRCA testing rates were observed. Patients with BRCAm were significantly more likely to utilize chemotherapy relative to BRCAwt. Mean duration of 1st line therapy was numerically lower among patients with BRCAm. With the advent of new treatment options, additional studies are warranted to validate these findings.

Editorial acknowledgement

Clinical trial identification

Legal entity responsible for the study

Pfizer.

Funding

Pfizer.

Disclosure

A. Niyazov: Employee, stockholder: Pfizer; R.G.W. Quek: Employee, ownership interest: Pfizer. All other authors have declared no conflicts of interest.