Fatigue among Long-Term Breast Cancer Survivors: A Controlled Cross-Sectional Study.

BACKGROUND: Fatigue is the most common and persistent symptom among women in the first five years after a breast cancer diagnosis. However, long-term prevalence of fatigue, among breast cancer survivors, needs further investigation. AIM: To compare fatigue experienced by long-term breast cancer survivors with that in a reference population and to evaluate the determinants of that fatigue. DESIGN AND SETTING: A cross-sectional cohort study of 350 breast cancer survivors ≥5 years after diagnosis and a reference population of 350 women matched by age and general practitioner. METHOD: Fatigue was measured using the Multidimensional Fatigue Inventory (MFI-20), and a sum score of >60 (multidimensional fatigue) was the primary outcome. Logistic regression was applied to compare the prevalence of multidimensional fatigue between the survivor and reference populations, adjusted for body mass index (BMI) and for cardiovascular and psychological variables. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were estimated. Logistic regression was applied to evaluate the determinants of multidimensional fatigue among the survivors. RESULTS: Breast cancer survivors (median 10 years after diagnosis), more often experienced multidimensional fatigue than the reference population (26.6% versus 15.4%; OR, 2.0 [95%CI, 1.4-2.9]), even after adjusting for confounders. The odds of multidimensional fatigue were also higher among survivors with symptoms of depression (32.2% versus 2.7%; OR, 17.0 [95%CI, 7.1-40.5]) or anxiety (41.9% versus 10.1%; OR, 6.4 [95%CI, 3.6-11.4]). CONCLUSION: One in four breast cancer survivors experience multidimensional fatigue and fatigue occurs more frequently than in women of the same age and general practitioner. This fatigue appears to be associated with symptoms of depression and anxiety.

Long-term survivors of early breast cancer treated with chemotherapy are characterized by a pro-inflammatory biomarker profile compared to matched controls.

BACKGROUND: Chemo- and radiotherapy for breast cancer (BC) can lead to cardiotoxicity even years after the initial treatment. The pathophysiology behind these late cardiac effects is poorly understood. Therefore, we studied a large panel of biomarkers from different pathophysiological domains in long-term BC survivors, and compared these to matched controls. METHODS AND RESULTS: In total 91 biomarkers were measured in 688 subjects: 342 BC survivors stratified either to treatment with chemotherapy ± radiotherapy (n = 170) or radiotherapy alone (n = 172) and matched controls. Mean age was 59 ± 9 years and 65 ± 8 years for women treated with chemotherapy ± radiotherapy and radiotherapy alone, respectively, with a mean time since treatment of 11 ± 5.5 years. No biomarkers were differentially expressed in survivors treated with radiotherapy alone vs. controls (P for all >0.1). In sharp contrast, a total of 19 biomarkers were elevated, relative to controls, in BC survivors treated with chemotherapy ± radiotherapy after correction for multiple comparisons (P <0.05 for all). Network analysis revealed upregulation of pathways relating to collagen degradation and activation of matrix metalloproteinases. Furthermore, several inflammatory biomarkers including growth differentiation factor 15, monocyte chemoattractant protein 1, chemokine (C-X-C motif) ligand 16, tumour necrosis factor super family member 13b and proprotein convertase subtilisin/kexin type 9, elevated in survivors treated with chemotherapy, showed an independent association with lower left ventricular ejection fraction. CONCLUSION: Breast cancer survivors treated with chemotherapy ± radiotherapy show a distinct biomarker profile associated with mild cardiac dysfunction even 10 years after treatment. These results suggest that an ongoing pro-inflammatory state and activation of matrix metalloproteinases following initial treatment with chemotherapy might play a role in the observed cardiac dysfunction in late BC survivors.

Cardiac Function After Radiation Therapy for Breast Cancer.

PURPOSE: The main purpose of this study was to test the hypothesis that incidental cardiac irradiation is associated with changes in cardiac function in breast cancer (BC) survivors treated with radiation therapy (RT). METHODS AND MATERIALS: We conducted a cross-sectional study consisting of 109 BC survivors treated with RT between 2005 and 2011. The endpoint was cardiac function, assessed by echocardiography. Systolic function was assessed with the left ventricular ejection fraction (LVEF) (n = 107) and the global longitudinal strain (GLS) of the left ventricle (LV) (n = 52). LV diastolic dysfunction (n = 109) was defined by e' at the lateral and septal region, which represents the relaxation velocity of the myocardium. The individual calculated RT dose parameters of the LV and coronary arteries were collected from 3-dimensional computed tomography-based planning data. Univariable and multivariable analysis using forward selection was performed to identify the best predictors of cardiac function. Robustness of selection was assessed using bootstrapping. The resulting multivariable linear regression model was presented for the endpoints of systolic and diastolic function. RESULTS: The median time between BC diagnosis and echocardiography was 7 years. No relation between RT dose parameters and LVEF was found. In the multivariable analysis for the endpoint GLS of the LV, the maximum dose to the left main coronary artery was most often selected across bootstrap samples. For decreased diastolic function, the most often selected model across bootstrap samples included age at time of BC diagnosis and hypertension at baseline. Cardiac dose-volume histogram parameters were less frequently selected for this endpoint. CONCLUSIONS: This study shows an association between individual cardiac dose distributions and GLS of the LV after RT for BC. No relation between RT dose parameters and LVEF was found. Diastolic function was most associated with age and hypertension at time of BC diagnosis. Further research is needed to make definitive conclusions.

Long-term outcome of cardiac function in a population-based cohort of breast cancer survivors: A cross-sectional study.

BACKGROUND: Chemotherapy and radiotherapy for breast cancer may lead to cardiac dysfunction, but the prevalence of long-term echocardiographic evidence of cardiac dysfunction is unknown among survivors. METHODS: In a cross-sectional study in primary care, we included 350 women who survived breast cancer for at least 5 years after diagnosis (treated with chemotherapy and/or radiotherapy) and 350 matched women (age and primary care physician). The primary outcome was cardiac dysfunction, defined as a left ventricular ejection fraction (LVEF) < 54% and an age-corrected decreased left ventricular (LV) diastolic function. Secondary outcomes included serum N-terminal pro B-type natriuretic peptide (NT-proBNP) levels, newly diagnosed cardiovascular diseases and cardiovascular medication. RESULTS: The median age at diagnosis was 63 (interquartile range (IQR) 57-68) years for the breast cancer survivors. Median follow-up after diagnosis was 10 (IQR 7-14) years. LVEF < 54% was present in 52 (15.3%) survivors and 24 (7%) controls (OR 2.4, 95%CI 1.4-4.0), but there was no significant increased prevalence of either LVEF < 50% or LV diastolic dysfunction. Serum NT-proBNP levels were increased, cardiovascular disease was more frequently diagnosed and cardiovascular medication use was more frequent among survivors compared with controls. These associations remained after adjustment for relevant covariates at diagnosis and at follow-up. CONCLUSIONS: In the long term, breast cancer survivors are at increased risk of mild LV systolic dysfunction, increased NT-proBNP levels, and cardiovascular disease compared with matched controls, even after adjustment for cardiovascular risk factors. Previous breast cancer treatment with chemotherapy, radiotherapy or both should be considered when assessing a patient's cardiovascular risk profile.