P173 THERAPEUTIC MANAGEMENT OF FLUOROPYRIMIDINE CARDIOTOXICITY: AN ANECDOTAL CASE

Abstract Background Fluoropirimidine represents one of the staple treatment of metastatic colorectal cancer; chemoterapy–based cardiotoxicity is unfortunately habitual in clinical practice. Raltitrexed could represent a valid alterantive to 5–FU in patients with cardiovascular comorbidities or in which 5–FU Has not been tolerated. Case Report Our patient is a 73 years–old woman, who underwent left colon surgical resection due to subocclusion; a whola body staging was not performed. After surgery, patient underwent CT scan,i n which multiple liver, lung and peritoneal metastases were identified. Biomolecular profiling assessment was perfomed (RAS, BRAF Wild type, DPYD*6 heterozigosis mutation). On January 2020, patient began FOLFIRI + PANITUMUMAB scheme as first line treatment (total cycles perfomed: 15). On January 2021, PD was detected though restaging imaging, and patient was subsequently treated with FOLFOX + BEvacizumab as second line. After 5 cycles, patient developed dyspnoea and palpitation; EKG was performed depicting Atrial fibrillation with heart rate: 73bpm, preserved biventricular systolic function and increased BNP and NT–pro–BNP serum concentration. According to patient’s high thromboembolic risk, oral anticoagulation (NOAC) was administered and multidisciplinary discussion was scheduled. NAO were preferred to Vitamin K antagonists due to drug–drug interactions; the treatment–of–choice was Apixaban 2.5 mg bis in die. Given the fact that aforementioned condition could have been attributed to 5–FU cardiologic toxicity, Raltitrexed was administered in lieu thereof 5–FU once synusal rythm was restored (TOMOX scheme). Bevacizumab administration was restored after a longer waiting (ca 2 months); the patient uderwent systematic and serial cardiologic assessment through clinical and EKG consults. Conclusion Our case report depicts the undelayable necessity of a Multidisciplinar collaboration in which oncologists and cardiologists could propose personalized treatment strategies which ensure correct antitumoral activities without significant and life–threatening toxicities.