Anthracycline-Induced Cardiotoxicity in Breast Cancer Patients: A Five-Year Retrospective Study in 10 Centers

Examining hypertension risk among Black and White breast cancer survivors

PURPOSE

Breast cancer survivors are at increased risk of cardiovascular dysfunction following their diagnosis; however, hypertension remains underexplored within this context. This retrospective cohort study examined the incidence of hypertension in breast cancer survivors and the association of race with hypertension risk among them.

METHODS

Data for this study were abstracted from the electronic health records of women diagnosed with Stages I-III breast cancer. Incident hypertension diagnosis was identified through International Classification of Diseases codes. Bivariate associations were tested using Student's t-test and chi-squared test of independence. Bivariable Cox regression analysis was used to determine demographic and clinical factors that may have been associated with the development of hypertension.

RESULTS

A total of 664 women were included. Most women were 50 years of age or younger (52.0%), White (33.0% Black), and received a mastectomy (80.6%). Overall, 45.5% of the cohort developed hypertension. The 1-year hypertension-free survival estimates were 47% (95% confidence interval [CI], 41-54) in Black women and 73% (95% CI, 69-77) in White women (p < 0.0001). Besides race, statistically significant predictors of hypertension included: age greater than 50 (vs. ≤50) (adjusted Hazard Ratio [HR]: 1.40; 95% CI, 1.09-1.80) and residing in a non-metropolitan area (vs. metropolitan) (adjusted HR: 1.60; 95% CI, 1.19-2.16).

CONCLUSIONS

This study suggests that breast cancer survivors who are older, Black, or residing in non-metropolitan areas may benefit from added surveillance and hypertension prevention strategies during treatment. Future studies are needed to identify contributors to the observed racial and geographic disparities.

Major cardiovascular adverse events in older adults with early-stage triple-negative breast cancer treated with adjuvant taxane + anthracycline versus taxane-based chemotherapy regimens: A SEER-medicare study

BACKGROUND

Triple-negative breast cancer (TNBC) is more aggressive as compared to other subtypes of breast cancer with characteristic metastatic patterns and a poor prognosis. The standard of care for early-stage TNBC is historically anthracycline and taxane-based chemotherapy (ATAX). Despite the effectiveness of this regimen, anthracyclines carry a small but important risk of cardiotoxicity, which is specifically a concern in the older population. This study evaluates major adverse cardiovascular events (MACE) in older women with TNBC treated with ATAX compared to taxane-based chemotherapy (TAX).

METHODS

Using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we identified women aged 66 and older with TNBC diagnosed between 2010 and 2015 (N = 2215). We compared patient and clinical characteristics according to adjuvant chemotherapy regimen (chemotherapy versus no chemotherapy and ATAX versus TAX). Logistic regression was performed to estimate the odds ratios (OR) and 95% confidence intervals (CIs), Kaplan-Meier survival curves were generated to estimate three-year overall survival (OS) and cancer specific survival (CSS). Cox proportional hazards models were used to analyze OS and CSS while controlling for patient and tumor characteristics. MACE was defined as acute myocardial infarction, heart failure, potentially fatal arrhythmia, and cerebral vascular incidence. Few patients experienced a cardiac death and therefore this was excluded in the analysis.

RESULTS

Of the 2215 patients in our cohort, most patients (n = 1334; 60.26%) received TAX compared to ATAX (n = 881; 39.78%). Patients who received ATAX were not statistically significantly more likely than those who received TAX to experience acute myocardial infarction, cerebral vascular accident (CVA), or potentially fatal arrhythmia when controlling for traditional risk factors. Among patients who experienced MACE, there was no difference in OS or CSS in patients who received TAX vs ATAX. Patients who received ATAX were less likely to develop heart failure than those who received TAX (OR 0.63, 95% CI [0.45-0.88], p < 0.01). Patients who developed MACE and who were > 76 years old had worse OS compared to those who experienced MACE and were age 66-75 years old (HR 1.67, 95% CI [1.07-2.62], p = 0.02).

CONCLUSION

Among older women with TNBC, receipt of adjuvant chemotherapy with ATAX was not associated with increased risk of major adverse cardiac events. For those who experienced a cardiac event, there was no difference in survival amongst those who received TAX vs ATAX. Other factors including additional chemotherapy toxicities should be investigated as a potential etiology for the inferior OS previously observed with ATAX vs TAX in older women with node negative or 1-3 positive lymph nodes.

Cardiotoxicity in breast cancer treatment: Causes and mitigation

Survivorship issues and treatment related toxicities have considerably increased in breast cancer patients following improved therapeutic options. Cardiotoxicity has been a major treatment related side effects in these patients. Despite this being a well-known entity, the real magnitude of the problem remains an enigma. The amount of research in mitigation of cardiotoxicity or its management in breast cancer survivors is limited and there is an urgent need for finding solutions for the problem. In this article, we are reviewing the agents that cause cardiotoxicity and suggesting a proposal for follow up of breast cancer survivors in an attempt to reduce the magnitude of impact on their quality of life.