Second-line chemotherapy with long-term low-dose oral etoposide in patients with advanced breast cancer.

In a phase II study, 27 patients with metastatic breast cancer were treated with oral etoposide as second-line chemotherapy at a dose of 50 mg/m2/day for 21 days, which courses were repeated every 4 weeks. Twenty-one patients were evaluable for response, and twenty-five for toxicity. In two (10%) patients a partial response was observed with a duration of 60 and 122 weeks respectively, and seven patients (33%) showed stable disease. Gastrointestinal toxicity was usually mild, though relatively frequent. Anemia grade II and III was observed in 20% of all courses (< 10% of all measurements), and leukopenia grade III and IV was observed in 22% of all courses (< 10% of all measurements). There was one toxic death. Reviewing the literature we calculated a response rate of intravenous etoposide treatment of 8% in 276 patients with metastatic breast cancer from 7 studies (response rates ranging between 0-14%), while (chronic) oral treatment caused a response rate of 19% in 145 patients from 8 different studies (response rates ranging between 0-35%).