INTERMITTENT CONTINUOUS-INFUSION OF FLUOROURACIL AND LOW-DOSE ORAL LEUCOVORIN IN PRETREATED BREAST-CANCER - A PILOT-STUDY

Aims and background: There is evidence that fluorouracil (FU), when ad ministered by protracted venous infusion, has antitumor activity in pr etreated breast cancer. The aims of the study were to assess, in a pop ulation of heavily pretreated breast cancer patients (greater than or equal to 2 lines of chemotherapy previously administered), the feasibi lity and activity of a new combination of oral L-leucovorin and contin uous FU infusion. Methods: Patients were treated with the following co mbination: oral L-leucovorin, 5 mg/m(2) days 1 through 14, plus FU, 25 0 mg/m(2) days 1 through 14, with cycles repeated every 21 days. Resul ts: Since November 1994, 22 patients have entered the study and 20 are assessable for response and side effects. Major patient characteristi cs were: ECOG performance status, 0-2; median age, 56 years (range, 41 -70); sites of metastasis, bone 9, lung 8, liver 2, pleura 7; 2 or mor e metastatic sites, 18. A total of 74 cycles has been administered (me dian/patient, 3 cycles). Five partial remissions (25%), 4 disease stab ilizations and 11 disease progressions have been observed. Median time to progression was 3 months (range 1-6+). Grade I-II mucositis was ob served in 8 patients and grade III-IV in 6 patients. Other side effect s have included diarrhea and thrombocytopenia. Conclusions: The schedu le has demonstrated moderate activity in heavily pretreated breast can cer, with mucositis as the dose-limiting toxicity.