Irinotecan inducing sinus pause bradycardia in a patient with small round cell cancer.

Irinotecan is a novel anticancer drug that has worked wonders in combination with other anticancer drugs. It can be used as a single chemotherapy agent in colonic cancer treatment or in combination with 5-fluorouracil. Irinotecan has been found a better salvage therapy in patients who are resistant to 5-fluorouracil. It is also used in combination with cisplatin and other drugs for cancers such as pleural mesothelioma, Ewing's sarcoma, lung cancer and others, and has helped reduce tumour burden. Irinotecan is generally associated with gastrointestinal side effects including nausea, vomiting and diarrhoea, while cardiovascular toxicity (5%) has been reported mainly as vasodilatation and possible bradycardia with no known incidence. A case was reported in 1998 by Miya et al of a 65-year-old man with bradycardia which was managed with atropine without modifications in the dosage of irinotecan or in the rate of infusion. We report a case of a patient with small round cell cancer who presented with sinus pause bradycardia after infusion with irinotecan. The patient was managed with atropine during chemotherapy. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.