Lifestyle modifications for patients with breast cancer to improve prognosis and optimize overall health

Abstract

A lthough more than 90% of patients with breast cancer have early stage disease at diagnosis, about 25% will eventually die of distant metastasis.1 Many patients with breast cancer seek information from a variety of sources about behaviours that may reduce their risk of recurrence.2 Making positive lifestyle changes can also be psychologically beneficial to patients by empowering them, since the feeling of loss of control is one of biggest challenges of a cancer diagnosis.In this review, we identify which lifestyle changes can be recommended to patients as an adjunct to standard breast cancer treatments, to reduce their risk of distant recurrence and death. We review the role of lifestyle factors, particularly weight management, exercise, diet, smoking, alcohol intake and vitamin supplementation, on the prognosis of patients with breast cancer. Our literature search is summarized in Box 1.It is challenging to study lifestyle factors independently, because patients who are more physically active often are leaner, eat a healthier diet and are typically less likely to drink excessive amounts of alcohol or smoke; however, many studies try to adjust for these confounders.3 Another limitation is the potential impact of lifestyle factors before diagnosis. 4 Regrettably, but understandably, we found very few randomized trials. How does body weight influence the prognosis for breast cancer?Women who gain weight during or after treatment of breast cancer have been consistently shown to be at higher risk of breast cancer-related death.5-7 Also, women who are overweight or obese at the time of diagnosis have a poorer prognosis.8 Proposed mechanisms of how obesity might affect breast cancer mortality include a rise in circulating insulin-like growth factor, elevated circulating sex hormones and production of proinflammatory cytokines.9-12 Another possible mechanism is metabolic syndrome (presence of at least three of the following five components: abdominal obesity, hypertension, low level of highdensity lipoproteins, high plasma glucose level and high triglyceride levels). 13 In a recent study involving early stage breast cancer survivors, patients with metabolic syndrome were at significantly increased risk of distant metastasis (hazard ratio [HR] 2.45, 95% confidence interval [CI] 1.24-4.82) compared with those without the syndrome. 13Most patients with breast cancer gain weight both during and after active treatment, and much of the weight is never lost. The average reported weight gain is 2.5-5 kg, 5 but a gain of 10 kg or more is not uncommon.14 The reasons for weight gain are multifactorial and include "stress eating," reduced activity because of fatigue or other treatment-related adverse effects, lowered metabolic rate from chemotherapy, and use of pre-and post-chemotherapy medications such as dexamethasone.14 Weight gain is most common in women who experience treatment-related menopause and is often accompanied by relative fat gain and muscle loss. 15Several observational studies have shown that gaining weight dur...

Can Nutrition Lower the Risk of Recurrence in Breast Cancer

“…A comprehensive metaanalysis of the non-skeletal effects of vitamin D supplementation showed a modest reduction of all cancer mortality (RR 0.88, 95% CI 0.78-0.98) [43]. In addition, higher serum 25-hydroxyvitamin D levels were found to be associated with lower breast cancer mortality (pooled RR 0.58, 95% CI 0.40-0.85; highest vs. lowest quintile: HR 0.56, 95% CI 0.40-0.70) [44]. However, there is no data available on the effect of vitamin D supplementation on breast cancer survival.…”

Obesity, Dietary Factors, Nutrition, and Breast Cancer Risk

“…In addition, physical activity during and after treatment can help patients to manage treatment side effects, reduce cancer-related fatigue, improve quality of life and functional capacity, promote alterations in bio-markers, and potentially enhance the overall prognosis and survival of breast cancer patients and survivors [168, 169]. On the other hand, in one study, adhering to a strict dietary intervention resulted in decreased sleep quality in breast cancer patients, indicating that changing dietary behaviors can be both challenging and stressful [160].…”

A randomized controlled trial of WATAAP to promote physical activity in colorectal and endometrial cancer survivors

“…Physical activity (PA) reduces the risk of cardiovascular disease (CVD), cancer, and cancer‐related death . In cancer survivors, PA may reduce the risk of recurrence . Sedentary behaviour may be an independent risk factor for cancer occurrence and mortality .…”