SYMPTOMATIC CARDIOTOXICITY ASSOCIATED WITH 5-FLUOROURACIL

A prospective cohort study was conducted in 35 hospitals with oncology units to determine the incidence of symptomatic cardiotoxicity in pat ients receiving continuous infusions of 5-fluorouracil (5-FU), and to identify risk factors that could contribute to the development of 5-FU -associated cardiotoxicity. A sample of 483 patients [197 (41%) women, overall average age +/- SD 60.9 +/- 11.9 yrs] were followed for one c ycle of 5-FU infusion. Thirty-eight (7.9%) patients had abrupt termina tion of the infusion. There were 9 (1.9%) cases of suspected or docume nted cardiotoxic events. Cardiotoxicity occurred in 7 (3.35%) of 209 p atients receiving their first course of 5-FU and in 2 (0.73%) other pa tients (p = 0.044). Based on univariate analysis, the following patien t groups were at elevated risk of cardiotoxicity: those with preexisti ng cardiac disease (RR = 6.83, p = 0.0023); patients receiving calcium channel blockers (RR = 4.75, p = 0.014); those receiving nitrates (RR = 9.18, p = 0.007); and patients receiving concomitant etoposide (RR = 10.32, p = 0.022). Patients with underlying cardiac disease require close monitoring while receiving continuous infusions of 5-FU. They sh ould be observed for signs and symptoms of cardiotoxicity, and vital s igns should be measured frequently. Continued reporting of 5-FU-associ ated cardiotoxicity is necessary to identify other patients at risk.