title: Eniluracil plus 5-fluorouracil and leucovorin: treatment for metastatic breast cancer patients in whom capecitabine treatment rapidly failed.
abstract: BACKGROUND
  As part of a comparative phase II study of eniluracil/5-FU/Lv vs. capecitabine (Xeloda), an oral 5-FU prodrug for MBC, patients with rapid PD during capecitabine therapy crossed over to take eniluracil/5-FU/Lv.
  
  
  METHODS
  Ten evaluable patients with radiologically documented PD within 70 days of capecitabine treatment were treated with a modified oral weekly eniluracil/5-FU/Lv regimen.
  
  
  RESULTS
  After switching to eniluracil/5-FU/Lv, 3 (30%) patients had PR. Six (60%) had SD, producing a total of 90% with PR or SD. The median PFS was 140 days (vs. 42.5 days for capecitabine). Four (40%) patients had > 7 months PFS. Eniluracil/5-FU/Lv was well tolerated with mild to moderate diarrhea and nausea as the most common side effects.
  
  
  CONCLUSIONS
  These positive efficacy and safety results encourage a larger study in patients with rapid PD during capecitabine treatment. Eniluracil/5-FU/Lv might enable these patients to continue with oral 5-FU rather than switching to the generally less well tolerated intravenous microtubule-interfering agents. In addition, the eniluracil/5-FU/Lv regimen might also provide any overall survival contribution of 5-FU that, for pharmacokinetic reasons, was not provided by capecitabine and would not be provided if these patients progressed directly to the other approved treatments.
authors.affiliation: Banner M.D. Anderson Cancer Center, Phoenix, AZ.
authors.forename: Edgardo
authors.initials: E
authors.lastname: Rivera
authors.affiliation: The Methodist Hospital Cancer Center, Houston, TX.
authors.forename: Jenny C
authors.initials: JC
authors.lastname: Chang
authors.affiliation: Road Clinical Hospital of the Russian Railways, St Petersburg, Russia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Semiglazov
authors.affiliation: Arkhangelsk Regional Clinical Oncology Center, Arkhangelsk, Russia.
authors.forename: Olga
authors.initials: O
authors.lastname: Burdaeva
authors.affiliation: MGK Consulting, LLC, Chapel Hill, NC.
authors.forename: M Gray
authors.initials: MG
authors.lastname: Kirby
authors.affiliation: Spector Consulting Services, Durham, NC. Electronic address: spectors@mindspring.com.
authors.forename: Thomas
authors.initials: T
authors.lastname: Spector
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D000069287:Capecitabine; D003841:Deoxycytidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage / Q000009:adverse effects; D008875:Middle Aged; D009362:Neoplasm Metastasis; D017211:Treatment Failure; D014498:Uracil / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives
chemical_list: D003841:Deoxycytidine; C073482:eniluracil; D014498:Uracil; D000069287:Capecitabine; D002955:Leucovorin; D005472:Fluorouracil
keywords: 5-ethynyluracil; 776C85; DPD; Dihydropyrimidine dehydrogenase; Xeloda