– Have you been diagnosed with breast cancer?
Here is why you should lose weight if you were overweight or obese before diagnosis, or if you gained weight during breast cancer treatment:
a) Obesity decreases breast cancer treatment efficacy:
- Triple negative patients without positive lymph nodes have a worst prognosis than normal weight patients. – Bonsang-Kitzis si colab., 2015
- Obesity decreases ER+/PR±/HER2+ breast cancer survival by diminishing Tamoxifen and Herceptin treatments efficacy. – Pande et al., 2014
- Overweight and obese non-metastatic breast cancer patients have a lower response to neoadjuvant chemotherapy – Litton et al., 2008
- Weight gain during chemotherapy increases the risks of recurrence and mortality – Thivat, 2010
- The antiestrogenic treatment with aromatase inhibitors (Letrozole, Anastrozole or Exemestane) has less efficacy in postmenopausal obese breast cancer patients – Ioannides et al. 2014
b) Obesity increases the incidence and amplitude of breast cancer treatment side effects:
- Obesity increases the risk of risk of persistent pain after breast cancer surgery. – Ding et al., 2017
- Obesity is associated with a nearly 12-fold increased odds of a postoperative complication after elective breast procedures. – Chen et al., 2011
- Obesity increases breast cancer secondary lymphedema risk. – DiSipio et al., 2013
- Obesity increases radiotherapy skin toxicity. – Kraus-Tiefenbacher et al., 2012
- Obesity associates an increased risk of depression – Ishii et al., 2016
- Increased adiposity decreases vitamin D bioavailability – Parikh et al., 2004
c) Breast cancer patients obesity increases the risk of metastasis:
- Obesity increases metastasis risk and decreases survival in ER-/PR±/HER2+ breast cancer patients – Mazarella et al., 2013
- Obesity increases the risk of lung and liver metastasis, and chemotherapy is less efficient in obese breast cancer patients – Osman and Hennessy, 2014
- Obesity increases metastasis risk – Strong et al., 2015; Dowling et al., 2016
- Obesity increases lung metastatis risk – Nagahashi et al., 2016
- Obesity increases metastasis risk and decreases survival in ER-/PR±/HER2± breast cancer patients – Wu et al., 2017
d) Obesity decreases breast cancer patients overall survival:
- Obesity is an indepenedent factor that increases the risks of metastasis and breast cancer specific mortality, adjuvant therapies efficacy being lower in obese and overweight breast cancer patients – Ewertz et al., 2010
- Obesity decreases overall survival independently of lymph node positivity – Kaviani et al., 2013
- Obesity and diabetes have a negative impact on breast cancer survival – Jiralerspong et al., 2013
- Obesity is an independent factor risk that decreases overall survival in ER+/PR±/HER2- postmenopausal breast cancer patients with lymph node involvment – Arce-Salinas et al., 2014; Scholtz et al., 2015
- Obesity decreases overall survival in ER+ breast cancer patients younger than 40 years of age – Copson et al., 2015
- Obesity increases breast cancer patients risk of mortality – Chan and Norat, 2015
Bonsang-Kitzis, Hélène, et al. “Beyond axillary lymph node metastasis, BMI and menopausal status are prognostic determinants for triple-negative breast cancer treated by neoadjuvant chemotherapy.” PloS one 10.12 (2015): e0144359.
Ding, Yuan-Yuan, et al. “Body mass index and persistent pain after breast cancer surgery: findings from the women’s healthy eating and living study and a meta-analysis.” Oncotarget 8.26 (2017): 43332.
Ioannides, S. J., et al. “Effect of obesity on aromatase inhibitor efficacy in postmenopausal, hormone receptor-positive breast cancer: a systematic review.” Breast cancer research and treatment 147.2 (2014): 237-248.
Kraus-Tiefenbacher, Uta, et al. “Factors of influence on acute skin toxicity of breast cancer patients treated with standard three-dimensional conformal radiotherapy (3D-CRT) after breast conserving surgery (BCS).” Radiation Oncology 7.1 (2012): 217.
Mazzarella, Luca, et al. “Obesity increases the incidence of distant metastases in oestrogen receptor-negative human epidermal growth factor receptor 2-positive breast cancer patients.” European Journal of Cancer 49.17 (2013): 3588-3597.
Osman, Mohammed A., and Bryan T. Hennessy. “Obesity Correlation With Metastases Development and Response to First-Line Metastatic Chemotherapy in Breast Cancer.” Clinical Medicine Insights. Oncology 9 (2014): 105-112.
Pande, Mala, et al. “Association between germline single nucleotide polymorphisms in the PI3K-AKT-mTOR pathway, obesity, and breast cancer disease-free survival.” Breast cancer research and treatment 147.2 (2014): 381-387.
Litton, Jennifer K., et al. “Relationship between obesity and pathologic response to neoadjuvant chemotherapy among women with operable breast cancer.” Journal of Clinical Oncology 26.25 (2008): 4072-4077.
Strong, Amy L., et al. “Leptin produced by obese adipose stromal/stem cells enhances proliferation and metastasis of estrogen receptor positive breast cancers.” Breast Cancer Research 17.1 (2015): 112.