Idarubicin and cyclophosphamide--an active oral chemotherapy regimen for advanced breast cancer

Between October 1993 and September 1994, 33 women with metastatic breast cancer aged between 29 and 74 years with a median age of 58 were entered into a study of oral chemotherapy from three UK centres. Patients by definition had metastatic disease and were fit and well with performance status 0 or 1 in 23 cases, 2 in seven cases and 3 in two cases (one missing). Five patients had received prior adjuvant CMF chemotherapy, nine first line non-anthracycline containing chemotherapy for relapse, eight patients second line non-anthracycline containing chemotherapy and all patients had had hormone therapy either as adjuvant or for relapsed disease. Adjuvant radiotherapy had been given to 17 and palliative radiotherapy to 12 patients. In nine patients there was one site of disease at start of therapy, in 10 two sites, in 11 three sites and in three patients four or more sites. The regimen comprised oral idarubicin 15 mg/m2 on day 1, 10 mg/m2 on days 2 and 3 and oral cyclophosphamide 250 mg/m2 (maximum 400 mg) on days 1, 2 and 3. Treatment was continued until disease progression or toxicity.

Overall 25% of 32 evaluable patients responded objectively including one complete response; 50% of patients had stable disease and 25% of patients progression. Among patients who had had no prior chemotherapy the objective response rate was 37.5%; 45% of patients had symptomatic improvement. The most common severe toxicity was granulocytopenia WHO grade 3 or more in 69.7% of patients. Thrombocytopenia grade 3 or 4 was seen in four patients. Six patients had documented infections and all but four patients had alopecia. All patients complained of mild or moderate fatigue. Nausea and vomiting occurred in 75% of patients but only four individuals had grade 3 toxicity. Two patients stopped therapy after myocardial infarction and one after impaired cardiac function was noted. The median time to progression was 2.7 months (1-11.5 months) and median survival time 8.8 months (1-13+ months).

The combination chemotherapy is active in heavily treated patients with manageable toxicity but there are problems in heavily pre-treated patients. There was good compliance in taking medication and at the doses chosen the drugs appear to be suitable for younger fitter patients.