Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23

World GI 2015 Press Release: Patients with Lowest BMI Have Shortest Survival in Pooled Analysis of Bevacizumab in Metastatic Colorectal Cancer

01 Jul 2015
Gastrointestinal cancers

BARCELONA-LUGANO – Patients with the lowest body mass index (BMI) had the shortest overall survival in an analysis of bevacizumab studies in metastatic colorectal cancer (mCRC) presented for the first time today (1 July 2015) at the ESMO 17th World Congress on Gastrointestinal Cancer 2015 in Barcelona.(1)

“There is good evidence that obesity increases the risk of getting colorectal cancer and that it increases the risk of colorectal cancer recurrence after curative therapy,” said lead study author Dr Yousuf Zafar, associate professor of medicine at Duke Cancer Institute in Durham, North Carolina. “What we did not know prior to these results is whether there is a relationship between obesity and survival in patients with metastatic colorectal cancer.”

He continued: “There is evidence that, at least in the US, obese patients may be at risk to receive lower doses of chemotherapy, so we hypothesised that obesity would be associated with worse survival in patients with colorectal cancer.”

The current study analysed overall survival and progression-free survival according to four categories of BMI (<25, 25-<30, 30-35, >35 kg/m2) in patients treated with bevacizumab in the first line for mCRC. The researchers used a pooled dataset of patients with previously untreated mCRC who received bevacizumab with chemotherapy in four large prospective US and European registry studies, namely BEAT, BRiTE, AWB and CONCERT.

A total of 6,128 patients were included in the analysis, which showed that patients with the lowest BMI (<25 kg/m2) had a significantly shorter overall survival than patients in the other BMI categories (see table). Progression-free survival was similar across all BMI subgroups.

Zafar said: “Our primary finding was that obesity was not associated with worse survival in mCRC. Contrary to our hypothesis, patients who had the lowest BMI were at risk of having the shortest survival. This effect persisted after adjusting for study, age, ECOG performance status, gender, and hypertension. We did not see any relationship between BMI and progression-free survival.”

With regard to how the findings might be explained, Zafar said: “When it comes to obesity and colorectal cancer incidence and recurrence, there is likely some biologic mechanism that increases that risk, which may be related to factors including insulin or insulin-like growth factor. However, in the relationship between obesity and survival in metastatic colorectal cancer, it’s likely that cancer-related cachexia overwhelmed any potential biologic harm from obesity or any potential inadequate dosing that obese patients may experience.”

He added: “These results suggest that cachexia is a fairly strong predictor of poor outcomes in these patients. This could be a biologic effect or a treatment pattern issue. Cachexia by itself is a poor prognostic indicator but there also may be a relationship between cachexia and how much treatment patients can tolerate. I would hypothesise that the lowest weight patients in our analysis received or tolerated less treatment.”

Patients with the lowest BMI had similar progression-free survival to those in the other BMI categories. Zafar explained: “It’s possible that the lowest weight patients may receive adequate first-line treatment but then are too sick to receive subsequent lines of therapy. That may be where we can focus more attention on improving their outcomes.”

Looking to the future of this research area, Zafar said: “An important next step in this work would be a closer study of how cachexia worsens patient outcomes in mCRC. We need to understand whether it is the biology of cachexia that harms these patients more, or whether their outcome is worsened by receipt of sub-par treatment. Or it could be a combination of both.”

Commenting on the data, Dr Roberto Labianca, Director of the Cancer Centre, Ospedale Giovanni XXIII in Bergamo, Italy, ESMO spokesperson, said: “This study is important because we can now consider BMI as a prognostic factor for patients with metastatic colorectal cancer. The clinical implication could be that patients with low BMI should be considered similar to patients with more aggressive cancer and probably they should be given more active treatment. For example, polychemotherapy instead of monotherapy or a biological plus chemotherapy instead of chemotherapy alone.”

“We need more follow up of course,” continued Labianca. “The next step could be to design a prospective clinical trial using BMI to stratify patients for treatment.”

Median overall survival (OS) and progression-free survival (PFS) according to BMI

Median overall survival (OS) and progression-free survival (PFS) according to BMI

Notes to Editors

  1. Abstract LBA-01 ‘Survival outcomes according to body mass index (BMI): results from a pooled analysis of 5 observational or phase IV studies of bevacizumab in metastatic colorectal cancer (mCRC)’ will be presented by Yousuf Zafar during Session I: Opening, Selected Abstracts, and Keynote Lecture on Wednesday 1 July, 14:15.

Information contained in this press release was provided by the abstracts authors and reflects the content of the studies. It does not necessarily express ESMO's point of view.

About the ESMO World Congress on Gastrointestinal Cancer

The ESMO World Congress on Gastrointestinal Cancer is the premier global event in the field, encompassing malignancies affecting every component of the gastrointestinal tract and aspects related to the care of patients with gastrointestinal cancer, including screening, diagnosis and the latest management options for common and uncommon tumours. It has been endorsed by leading professional societies and organizations. The Congress is developed and managed by Imedex®, LLC.

About the European Society for Medical Oncology

The European Society for Medical Oncology (ESMO) is the leading European professional organization committed to advancing the specialty of medical oncology and promoting a multidisciplinary approach to cancer treatment and care.

ESMO’s mission is to advance cancer care and cure through fostering and disseminating good science that leads to better medicine and determines best practice.

ESMO’s scientific journal, Annals of Oncology, ranks among the top clinical oncology journals worldwide. ESMO events are the meeting place in Europe for medical oncologists to update their knowledge, to network and to exchange ideas.

Abstract LBA-01

Survival outcomes according to body mass index (BMI): results from a pooled analysis of 5 observational or phase IV studies of bevacizumab in metastatic colorectal cancer (mCRC)
Y. Zafar1, J. Hubbard2, E. Van Cutsem3, F. Hermann4, A.J. Storm5, E. Gomez5, C. Revil5, A. Grothey2
1Duke University Medical Center, Durham, North Carolina, 2Mayo Clinic, Rochester, Minnesota, 3Leuven Cancer Institute, University Hospitals Leuven, Leuven, Belgium, 4University Hospitals Leuven, Leuven, Belgium, 5F. Hoffmann-La Roche, Ltd., Basel, Switzerland

Introduction: High BMI has been associated with increased risk of colorectal cancer. However, little is known about how BMI impacts outcomes for patients already diagnosed with mCRC. Here we describe an analysis of overall survival (OS) and progression-free survival (PFS) according to BMI in a pooled dataset of patients treated in prospective, observational studies.

Methods: Data from patients with previously untreated mCRC who received bevacizumab with chemotherapy were pooled from the prospective BEAT (ex-USA), BRiTE (USA), AWB (Germany), CONCERT (France), and ARIES (USA) studies. OS and PFS were evaluated via the Kaplan-Meier method in first-line patients stratified by baseline BMI categories. The ARIES study did not calculate patient BMI; data from ARIES were excluded from the present analyses.

Results: BMI data were available for 6128 of 7688 patients. Median BMI for all patients was 25.3 kg/m2 (IQR: 22.6–28.7). Median OS and PFS according to patients grouped by BMI are shown in the table.

Conclusion: In this pooled dataset of patients with mCRC treated with first-line bevacizumab and chemotherapy in observational/phase IV trials, patients with the lowest BMI had shorter median OS, suggesting that low BMI could be a poor-prognostic factor. PFS was similar between subgroups. Additional analyses, including adjusted Cox models supporting this finding will be presented at the meeting.

Last update: 01 Jul 2015

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings
  • Necessary cookies enable core functionality. The website cannot function properly without these cookies, and you can only disable them by changing your browser preferences.