Method: From 2016 to 2017, 2,127 women newly-diagnosed with breast cancer were prospectively recruited. Participants' cardiovascular biomarkers were measured prior to adjuvant treatment decision-making. Clinical data and medical histories were obtained from hospital records. Adjuvant treatment decisions were collated 6-8 months after recruitment. A priori risk of cardiotoxicity was predicted using the Cardiotoxicity Risk Score.
Results: Mean age was 54 years. Eighty-five patients had pre-existing cardiac diseases and 30 had prior stroke. Baseline prevalence of hypertension was 47.8%. Close to 20% had diabetes mellitus, or were obese. Dyslipidaemia was present in 65.3%. The proportion of women presenting with ≥2 modifiable CVD risk factors at initial cancer diagnosis was substantial, irrespective of age. Significant ethnic variations were observed. Multivariable analyses showed that pre-existing CVD was consistently associated with lower administration of adjuvant breast cancer therapies (odds ratio for chemotherapy: 0.32, 95% confidence interval: 0.17-0.58). However, presence of multiple risk factors of CVD did not appear to influence adjuvant treatment decision-making. In this study, 63.6% of patients were predicted to have high risks of developing cardiotoxicities attributed to a high baseline burden of CVD risk factors and anthracycline administration.
Conclusion: While recent guidelines recommend routine assessment of cardiovascular comorbidities in cancer patients prior to initiation of anticancer therapies, this study highlights the prevailing gap in knowledge on how such data may be used to optimise cancer treatment decision-making.
METHODS: Data of 3,100 Malaysian women with nonmetastatic breast cancer diagnosed between 2010 and 2017 were analyzed. Adherence to the Malaysian Clinical Practice Guidelines for Management of Breast Cancer second Edition was measured. Outcomes comprised overall survival and event-free survival.
RESULTS: Guideline adherence for chemotherapy, radiotherapy, hormonal therapy, and targeted therapy were 61.7%, 79.2%, 85.1%, and 26.2%, respectively. Older age was generally associated with lower adherence to guidelines. Compared with patients who were treated according to treatment guidelines, overall survival and event-free survival were substantially lower in patients who were not treated accordingly; hazard ratios for all-cause mortality were 1.69 (95% CI, 1.29 to 2.22), 2.59 (95% CI, 1.76 to 3.81), 3.08 (95% CI, 1.94 to 4.88), and 4.48 (95% CI, 1.98 to 10.13) for chemotherapy, radiotherapy, hormone therapy, and targeted therapy, respectively. Study inferences remain unchanged following sensitivity analyses.
CONCLUSION: Our study findings appear to suggest that adherence to treatment guidelines that have been adapted for resource-limited settings may still provide effective guidance in improving breast cancer outcomes.