Eniluracil plus 5-fluorouracil and leucovorin: treatment for metastatic breast cancer patients in whom capecitabine treatment rapidly failed.

As part of a comparative phase II study of eniluracil plus 5-fluorouracil (5-FU) and leucovorin (Lv) vs. capecitabine, an oral 5-FU prodrug for metastatic breast cancer (MBC), 10 evaluable patients with rapid disease progression (PD) during capecitabine treatment crossed over to take eniluracil/5-FU/Lv. Of these patients, 3 had partial tumor response (PR), 6 had stable disease (SD), and 4 had > 7 months progression-free survival (PFS) with eniluracil/5-FU/Lv treatment.