Patients with gastrointestinal cancer treated with fluoropyrimidine chemotherapy benefit from an almost eightfold reduction in the risk of all-cause mortality, despite a slight increase in the risk for cardiovascular toxicity, according to recent findings published by Abiodun et al in JACC: CardioOncology.
Preexisting cardiovascular disease did not confer an increased risk of cardiotoxicity compared with the overall study population.
“The markedly improved overall survival with fluoropyrimidines in patients with gastrointestinal cancer significantly outweighs the small risk of cardiac arrhythmia and arrest," wrote Aderonke T. Abiodun, MBChB, of the Institute of Cardiovascular Science, University College London, and Barts Heart Centre, Barts Health NHS Trust, and colleagues. “Oncologists should take this into consideration for decision-making to avoid undue clinical conservatism, particularly in patients with cardiovascular disease.”
Study Methods and Results
Many physicians are concerned about cardiovascular risks with first-line fluoropyrimidine chemotherapy for patients with gastrointestinal cancers, especially for those with cardiac comorbidities, and choose alternate treatment options to avoid the cardiotoxicity concerns. Researchers sought to quantify the risk/benefit of fluoropyrimidine for these patients.
They conducted a national observational cohort study of 103,110 patients with stage II to IV esophageal or gastric cancer and stage III or IV colorectal cancer, with data from the Virtual Cardio-Oncology Research Initiative. All patients were eligible for front-line fluoropyrimidine-based chemotherapy, but only 28.2% of patients after the 8-week grace period received fluoropyrimidine.
The researchers highlighted that their study presented real-world clinical findings and thus included patients with cardiovascular risk factors and preexisting conditions that would have been excluded from participating in clinical trials.
The absolute risk of death at 1 year was lower for patients who received fluoropyrimidine-based treatment than those who received alternate therapies (risk difference [RD] = –7.7%; 95% confidence interval [CI] = –8.7% to –6.7%). However, these patients did have a slightly increased risk of experiencing acute cardiovascular events (RD = 0.9%; 95% CI = 0.0%–1.9%), which mostly included arrhythmia (RD = 0.8%; 95% CI = 0.1%–1.6%) and cardiac arrest (RD = 0.3%; 95% CI = 0.1%–0.5%). Cardiovascular events, however, were also frequently seen in the no-fluoropyrimidine group (14.9% vs 15.8% with fluoropyrimidine), and the rates of heart failure, acute coronary syndrome, and coronary interventions were similar between the two groups.
“Irrespective of treatment strategy, cardiovascular events were high, with one in seven patients experiencing an event within the 12-month follow-up period,” the study authors noted.
Disclosure: For full disclosures of the study authors, visit jacc.org.
