Clinical efficacy of low-dose weekly docetaxel combined with oral 5'-deoxy-5-fluorouridine (5'-DFUR) in advanced or metastatic breast cancer: a pilot trial

Docetaxel (TXT) has been shown to be an up-regulator of human pyrimidine nucleoside phosphorylase (PyNPase) in tumors. We have tried to use the combination of low-dose weekly TXT with 5'-DFUR (LD + D) in patients with advanced or metastatic breast cancer. In this study, we compared the clinical efficacy of LD + D with that of conventional full-dose TXT (FD) and that of low-dose weekly TXT (LD). Twenty-one patients received 3 or 4 cycles of FD 60 mg/m2 every 3 or 4 weeks (group I), 14 patients received 8 cycles of LD 20-30 mg/m2 every week (group II) and 25 patients received 8 cycles of LD 20-30 mg/m2 weekly with oral 5'-DFUR 600-1,200 mg per day (group III). The overall response rates of groups I, II and III were 29%, 29% and 52% (p = 0.24), respectively. Grade 3-4 neutropenia was observed in 91% of group I, 6% of group II and 3% of group III. Nausea was present in 27% of group I, 28% of group II and 40% of group III. Higher incidence of gastrointestinal symptoms was found in LD + D, but the symptoms abated when the doses of 5'-DFUR were reduced. Low-dose weekly TXT with oral 5'-DFUR produced a higher response rate, but less hematologic toxicity than full-dose TXT, suggesting that this combination therapy is clinically useful and may be effective for patients with advanced or metastatic breast cancer.