Obesity or overweight is associated with worse pathological response to neoadjuvant chemotherapy among Chinese women with breast cancer

PLoS One. 2012;7(7):e41380. doi: 10.1371/journal.pone.0041380. Epub 2012 Jul 25.

Abstract

Background: To evaluate the relationship between body mass index (BMI) and response to neoadjuvant chemotherapy (NCT) for breast cancer among Chinese women.

Patients and methods: A total of 307 eligible patients were assigned to receive four cycles of paclitaxel and carboplatin before standard surgery for breast cancer from 2007 to 2011 at Shanghai Cancer Hospital. The patients were categorized as obese, overweight, normal weight, or underweight based on BMI according to World Health Organization (WHO) criteria. Pathological complete response (pCR) was defined as no invasive cancer in the breast or axillary tissue. A logistic regression and the Chi-squared test were used for detecting the predictors of pCR and determining the relationship between BMI category and pCR rate in the subgroup analysis with respect to other variables.

Results: Categorical BMI, estrogen receptor (ER), and progesterone receptor (PR) status were independent predictors of pCR according to the multivariate analysis. Patients with BMI≥25 were less likely to achieve a pCR to NCT compared with patients with BMI<25 (Odds ratio: 0.454, p = 0.033, multivariate analysis). In the subgroup analysis, the predictive value of BMI for pCR to NCT was significantly shown in post-menopausal patients (p = 0.004) and hormonal receptor status-negative patients (p = 0.038). The incidence of treatment-induced toxicity was similar among the different BMI categories.

Conclusion: Higher BMI was associated with worse pCR to NCT. Further approaches to investigating the mechanism of this influence of BMI on treatment response and a more appropriate schedule for calculating NCT dose for high-BMI-patients should be considered.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Asian Continental Ancestry Group
  • Body Mass Index*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology*
  • Breast Neoplasms / therapy*
  • China
  • Estrogen Receptor alpha / metabolism
  • Female
  • Humans
  • Middle Aged
  • Neoadjuvant Therapy / methods*
  • Neoplasm Proteins / metabolism
  • Obesity / metabolism
  • Obesity / pathology*
  • Receptors, Progesterone / metabolism

Substances

  • Estrogen Receptor alpha
  • Neoplasm Proteins
  • Receptors, Progesterone

Grant support

This research was supported by Multidiscipline Comprehensive Treatment Cooperation Group, Foundation of Fudan University Cancer Hospital, Shanghai, China (DXK200801), the Key Clinical Program of the Ministry of Health (2010–2012), the 2009 Youth Foundation of Shanghai Public Health Bureau, the 2009 Youth Foundation of Shanghai Medical College, the Shanghai United Developing Technology Project of Municipal Hospitals (SHDC12010116), the National Natural Science Foundation of China (30971143, 30972936, 81001169), and the Shanghai Committee of Science and Technology Fund for 2011 Qimingxing Project (11QA1401400). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.