Acceleration of interstitial lung disease induced by raltitrexed

Introduction Raltitrexed is a folate analogue, which selectively inhibits thymidylate synthase, used in the treatment of colorectal carcinoma. Common side effects include asthenia and gastrointestinal and haematological toxicities. Case report We present the case of a 74-year-old gentleman with incidental mild interstitial lung disease on preoperative staging CT Chest who developed acute breathlessness whilst undergoing adjuvant raltitrexed treatment for a completely excised colorectal adenocarcinoma. Management and outcome Discontinuation of raltitrexed and a course of steroid therapy resulted in resolution of symptoms, mirrored by an improvement in lung function tests. Discussion The clinical pattern of rapid progression with steroid response highlights the potential for significant acceleration of interstitial lung disease by raltitrexed