Abstract 3608
Background
High BMI has been repeatedly identified as a risk factor for breast cancer (BC), but also as an adverse prognostic factor in women with early-stage BC. Little is known about its impact on outcome in patients with metastatic BC (MBC).
Methods
We used the National ESME-MBC cohort, which includes all consecutive patients (pts) newly diagnosed with MBC between Jan 2008 and Dec 2016 in 18 French comprehensive cancer centres. Women with available BMI at the diagnosis of MBC were selected. Four groups were defined according to WHO classification: underweight (BMI < 18.5 kg/m2), normal weight (18.5-24.9), overweight (25.0-29.9) and obese (≥30.0). Multivariate Cox analyses for OS were conducted in the whole population (primary objective). OS and 1st line progression-free survival (PFS) in subtypes (HER2+, Triple negative BC (TNBC) and HR+ HER2-) were secondary objectives.
Results
Of 22 463 patients in the ESME cohort, 12 999 women had BMI data available. Med BMI was 24.9 kg/m2 (range 12.1-66.5). Pts characteristics are reported in Table. Obesity was associated with more de novo MBC, while underweight pts had more aggressive features. Median follow-up was 48.6 months. Median OS was 47.4 months (95% CI [46.2-48.5]). By multivariate analysis, age, visceral metastases, time to MBC, number of metastatic sites, tumor subtype and BMI were independent predictors for OS. Underweight (but not overweight or obesity) was associated with a worse prognosis (HR 1.29, 95%CI [1.16-1.44]), and this was true in each tumour subtype. Median 1st line PFS was 12.2 months, with similar multivariate results.Table:
367P
Underweight | Normal weight | Overweight | Obese | p | |
---|---|---|---|---|---|
N | 637 (5%) | 6020 (46%) | 3708 (29%) | 2634 (20%) | |
Age at MBC diagnosis (med) | 58 | 58 | 61 | 60 | <0.001 |
De novo MBC | 228 (36%) | 1939 (32%) | 1389 (37%) | 1132 (43%) | 0.000 |
Time to MBC (med, months) | 24 | 33 | 27 | 18 | <0.001 |
Visceral metastases | 400 (63%) | 3543 (59%) | 2148 (58%) | 1484 (56%) | 0.012 |
Subtype HR+HER2- | 354 (56%) | 3566 (59%) | 2311 (62%) | 1633 (62%) | 0.000 |
HER2+ | 131 (21%) | 1295 (21%) | 725 (20%) | 545 (21%) | |
TNBC | 105 (16%) | 860 (14%) | 499 (13%) | 345 (13%) | |
>3 metastatic sites | 180 (28%) | 1306 (22%) | 753 (20%) | 553 (21%) | 0.000 |
Median OS (95% CI) | 33 (29-40) | 47 (45-49) | 49 (47-51) | 48 (45-51) |
Conclusions
Unlike in early-stage BC, overweight and obesity do not seem associated with poorer OS in MBC women, whatever the subtype, on the opposite of underweight.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
M. Robain: Research grant / Funding (institution), ESME plateform support: Roche; Research grant / Funding (institution), ESME plateform support: AstraZeneca; Research grant / Funding (institution), ESME plateform support: Pfizer; Research grant / Funding (institution), ESME plateform support: BMS; Research grant / Funding (institution), ESME plateform support: DAIICHI Sankyo. All other authors have declared no conflicts of interest.
Resources from the same session
4732 - Progesterone Receptor Isoform Ratio Dictates Antiprogestins/Progestins Effects on Metastatic Breast Cancer Models
Presenter: Maria Abascal
Session: Poster Display session 2
Resources:
Abstract
5737 - PAM50 and CGH-array genomic characterization of HER2-Equivocal Breast Cancers defined by the 2018 ASCO/CAP recommendations.
Presenter: Carine Ngo
Session: Poster Display session 2
Resources:
Abstract
1096 - OncotypeDX® predictive nomogram for recurrence score output: a machine learning system based on quantitative immunochemistry analysis - ADAPTED01
Presenter: Fabio Marazzi
Session: Poster Display session 2
Resources:
Abstract
5426 - Geriatric parameters predict both disease-related and patient-reported outcomes in older patients with breast cancer
Presenter: Willeke van der Plas-Krijgsman
Session: Poster Display session 2
Resources:
Abstract
5865 - Patients with a 21-gene assay in South East London differ from the TAILORx trial population
Presenter: Charalampos Gousis
Session: Poster Display session 2
Resources:
Abstract
1312 - Predictive tools in adjuvant breast cancer – what is the standard of evidence supporting their utility? A literature review examining validation of Adjuvant!, Cancermath and NHS Predict
Presenter: Alice Loft
Session: Poster Display session 2
Resources:
Abstract
2445 - Oncologic outcome of invasive lobular carcinoma: Is it different from that of invasive ductal carcinoma?
Presenter: Hee Jun Choi
Session: Poster Display session 2
Resources:
Abstract
2476 - Pathologic response and survival efficacy in patients with initial nodal involvement after neoadjuvant chemotherapy in early breast cancer
Presenter: SERAFIN MORALES Murillo
Session: Poster Display session 2
Resources:
Abstract
3761 - Chemotherapy-induced amenorrhea: prognostic impact on premenopausal Egyptian patients with breast cancer
Presenter: Khaled Abdel Karim
Session: Poster Display session 2
Resources:
Abstract
4687 - Predicting the presence of breast cancer using circulating small RNA in the serum
Presenter: Yumiko Koi
Session: Poster Display session 2
Resources:
Abstract