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
3911 - Defining a SUV decrease cut-off in PET/CT response monitoring after one cycle of preoperative breast cancer chemotherapy
Presenter: Marcin Kubeczko
Session: Poster Display session 2
Resources:
Abstract
1849 - Effect of thioredoxin 1 quantity detection to complement the mammography in breast cancer diagnosis
Presenter: Younju Lee
Session: Poster Display session 2
Resources:
Abstract
2221 - Identification of ultralow risk breast cancer patients (probable overdiagnosis)
Presenter: Salvador Gamez Casado
Session: Poster Display session 2
Resources:
Abstract
5291 - Prevalence of Vitamin D3 deficiency among women with early breast cancer receiving chemotherapy in an oncology dayward.
Presenter: Warner Finstad
Session: Poster Display session 2
Resources:
Abstract
4247 - Changes in ER pathway activity score during neoadjuvant letrozole to assess therapy response and predict disease free survival (DFS) in ER positive breast cancer patients
Presenter: Arran Turnbull
Session: Poster Display session 2
Resources:
Abstract
568 - Second primary malignancies in patients with breast cancer.
Presenter: Carlos Erasun Lecuona
Session: Poster Display session 2
Resources:
Abstract
1428 - Phase II randomized trial of neoadjuvant trastuzumab and pertuzumab (TP) with either palbociclib + letrozole (Pal+L) or paclitaxel (Pac) for elderly patients with estrogen receptor & HER2 positive (ER+/HER2+) Breast Cancer (BC) (International Breast Cancer Study Group IBCSG 55-17, TOUCH)
Presenter: Laura Biganzoli
Session: Poster Display session 2
Resources:
Abstract
1479 - Neoadjuvant HER2-targeted therapy with or without immunotherapy with pembrolizumab (neoHIP): an open label randomized phase 2 trial
Presenter: Heather McArthur
Session: Poster Display session 2
Resources:
Abstract
1481 - A randomized phase 2 study of peri-operative ipilimumab, nivolumab and cryoablation versus standard care in women with residual, early stage/resectable, triple negative breast cancer after standard-of-care neoadjuvant chemotherapy
Presenter: Heather McArthur
Session: Poster Display session 2
Resources:
Abstract
4334 - ALEXANDRA/IMpassion030: A phase 3 study of standard adjuvant chemotherapy with or without atezolizumab in early stage triple negative breast cancer.
Presenter: Michail Ignatiadis
Session: Poster Display session 2
Resources:
Abstract