Recently, high-dose FEC (fluorouracil, epirubicin, and cyclophosphamide) has 
been increasingly used in adjuvant chemotherapy for breast cancer in Japan. 
However, the safety and tolerability of high-dose FEC are not well evaluated in 
Japanese breast cancer patients. We studied the feasibility of FEC (75) 
(fluorouracil: 500 mg/m(2), epirubicin: 75 mg/m(2), and cyclophosphamide:500 
mg/m(2), q 3 w, 6 cycles) as adjuvant chemotherapy for 59 primary breast cancer 
patients. Out of these patients, 56 (94.9%) finished 6 cycles-FEC. The mean 
epirubicin dose received was 431.7 mg/m(2) (95.9% of the intended dose of 450 
mg/m(2)). Forty-five (76.2%) of 59 patients experienced neutropenia of grade 3 
or 4, while the rates of febrile neutropenia (grade 3) and infection (grade 2) 
were 3.4% and 10.2%, respectively. Anemia (88.2%), fatigue (42.4%), nausea 
(40.6%), liver dysfunction (40.7%), and vomiting (18.7%) occurred, however most 
of them were mild and categorized into grade 1 or 2. No patients developed any 
cardiac failure symptoms. This study shows FEC (75) is well tolerable as 
adjuvant chemotherapy for Japanese breast cancer patients.