J Cancer 2015; 6(4):310-318. doi:10.7150/jca.10580

Research Paper

Association of Body Mass Index Changes during Neoadjuvant Chemotherapy with Pathologic Complete Response and Clinical Outcomes in Patients with Locally Advanced Breast Cancer

Takahiro Kogawa1, Tamer M. Fouad1, Caimiao Wei2, Hiroko Masuda1, Kazuharu Kai1, Takeo Fujii1, Randa El-Zein 3, Mariana Chavez-MacGregor1, Jennifer K. Litton1, Abenaa Brewster1, Ricardo H. Alvarez1, Gabriel N. Hortobagyi1, Vicente Valero1, Richard Theriault1, Naoto T. Ueno1 ✉

1. Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
2. Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
3. Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

Abstract

The purpose of this study was to determine the association between body mass index (BMI) measurements (baseline BMI and changes in BMI during neoadjuvant systemic treatment [NST]) and clinical efficacy (pathologic complete response [pCR] rate and survival outcomes) in locally advanced breast cancer (LABC). We hypothesized that high baseline BMI and increases in BMI during NST are associated with lower pCR rates and poorer clinical outcomes in LABC.

We retrospectively reviewed the medical records of 1002 patients, 204 with primary inflammatory breast cancer (IBC) and 798 with stage III non-IBC, who underwent standard NST and definitive surgery between November 1, 2006, and December 31, 2012.

The median follow-up time for the survivors was 19.6 months (0.4 - 67.8 months). The pCR rates of patients whose BMI increased or decreased were 23.2% and 18.1%, respectively, (p=0.048). The unadjusted overall survival (OS) was significantly better in the group with increased BMI (p=0.006). However, increased BMI was not an independent predictor of pCR and clinical outcomes (recurrence-free survival and OS) after adjusting for other clinical variables. In subset analyses, increased BMI as a continuous variable was an independent predictor of higher pCR rates in the normal BMI/underweight group (odds ratio [OR]=1.35, 95% confidence interval [CI]: 1.06-0.71, p=0.015). Increased BMI (BMI change ≥0 vs. <0) was also an independent predictor of pCR (OR=1.65, 95% CI: 1.00-2.72, p=0.049) in the postmenopausal group.

Our results show that increasing BMI shows improved clinical outcome in terms of better pCR rates in normal BMI/underweight group and in the postmenopausal group. These results contradict previously reported findings on the association between high BMI and poor clinical efficacy regarding pCR rate and survival outcomes in early-stage breast cancer. Thus, the role of BMI in breast cancer may depend on patients' clinical characteristics such as advanced stage.

Keywords: Breast cancer, Inflammatory breast cancer, Body mass index, Body mass index change, Predictive factor, Pathological complete response

This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY-NC) License. See http://ivyspring.com/terms for full terms and conditions.
How to cite this article:
Kogawa T, Fouad TM, Wei C, Masuda H, Kai K, Fujii T, El-Zein R, Chavez-MacGregor M, Litton JK, Brewster A, Alvarez RH, Hortobagyi GN, Valero V, Theriault R, Ueno NT. Association of Body Mass Index Changes during Neoadjuvant Chemotherapy with Pathologic Complete Response and Clinical Outcomes in Patients with Locally Advanced Breast Cancer. J Cancer 2015; 6(4):310-318. doi:10.7150/jca.10580. Available from http://www.jcancer.org/v06p0310.htm