title: 5-FU-induced hyperammonemic encephalopathy in a case of metastatic rectal adenocarcinoid successfully rechallenged with the fluoropyrimidine analog, capecitabine.
abstract: Neurological complications of both fluorouracil (5-FU) and its oral prodrug, capecitabine, have been described in the literature. This study reported the case of a 70-year-old female with metastatic adenocarcinoid of the rectum who developed hyperammonemic encephalopathy, following infusional 5-FU therapy, manifesting itself as intractable nausea, vomiting, confusion and disorientation. Interestingly, when the patient was rechallenged with the fluoropyrimidine analog, capecitabine, neither hyperammonemia nor symptom recurrence was observed. 5-FU is an integral component of effective anti-neoplastic treatment for metastatic colorectal cancer, but is often discontinued when neurotoxicity develops. This case highlighted the use of capecitabine as an alternative for patients who have demonstrated evidence of 5-FU-induced hyperammonemic encephalopathy. Re-challenging the patient with capecitabine, at a low daily dose intensity, accounted for the overall tolerability of the treatment, as demonstrated by normal ammonia levels and the lack of neurological symptoms.
authors.affiliation: Roswell Park Cancer Institute, Buffalo, NY 14203, USA.
authors.forename: Pooja P
authors.initials: PP
authors.lastname: Advani
authors.forename: Marwan G
authors.initials: MG
authors.lastname: Fakih
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000556:secondary; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D001927:Brain Diseases / Q000139:chemically induced* / Q000188:drug therapy*; D000069287:Capecitabine; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D005472:Fluorouracil / Q000009:adverse effects* / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006801:Humans; D022124:Hyperammonemia / Q000139:chemically induced* / Q000188:drug therapy*; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000556:secondary; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D016896:Treatment Outcome
chemical_list: D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D000069287:Capecitabine; D005472:Fluorouracil