Case Report
A 16-year-old female diagnosed with stage IVA NPC began treatment with a regimen of Cisplatin and 5-FU per COG protocol ARAR0331. She presented with a one-year history of migraine headaches and left sided cranial nerve VII palsy secondary to tumor compression [Fig. 1]. She had no known underlying cardiovascular disease and an echocardiogram prior to the initiation of chemotherapy demonstrated normal cardiac function (left ventricular ejection fraction (LV EF) 68%).
Planned initial chemotherapy regimen consisted of 3 cycles of Cisplatin (80mg/m2/day) on day 1 and 5-FU (1,000 mg/m2/day continuous infusion) on days 1-4. On day 3 of cycle 1, she developed acute hypotension and tachycardia. Electrocardiogram demonstrated sinus tachycardia and echocardiogram showed significantly compromised cardiac function, with LV EF of 33%. She was transferred to the pediatric ICU and milrinone infusion was initiated.
Cardiac function continued to decline over subsequent days [Fig. 2]. Due to the temporal relationship, 5-FU cardiotoxicity was considered as the etiology of the patient’s cardiomyopathy. At hour 60 after the completion of 5-FU infusion, uridine triacetate therapy was initiated (10 grams every 6 hours orally for 5 days). Within 48 hours, LV EF improved to 48%. By 96 hours, LV EF normalized and milrinone was weaned off. She completed the full regimen of uridine triacetate (total of 20 doses). The patient continued the chemotherapy regimen with cisplatin as monotherapy, and subsequently received external beam radiation therapy for local control. The patient responded to this therapy and remains in PET-negative remission 17 months post-therapy. The most recent echocardiogram performed approximately 14 months following this event shows no evidence of cardiac dysfunction (LV EF 60%).