Impressive survival data with semimetronomic oral chemotherapy with old agents in heavily treated metastatic breast cancer patients

Abstract

1082 Background: To assess the efficacy of semi-metronomic regimen metronomic cyclophosphomide with oral etoposide in heavily treated patients with metastatic breast cancer. Methods: Consecutive metastatic breast cancer (MBC) patients predominantly refractory to antracyclines, taxanes, and antimetabolites receiving semi-metronomic regimen of metronomic cyclophosphomide with oral etoposide were evaluated for clinical efficacy and toxicity. This novel regimen comprised of continuous oral cyclophosphomide 50 mg/day, and oral etoposide given as 2 x 50 mg/day for 5 days. Results: A total of 42 MBC patients received this treatment in 2.5 years (May 2005-October 2008). The median age was 51.5 (29–81), ER and/or PR receptor status was positive in 67%, and c-erb-B2 overexpression existed in 50%. The biologically favorable group, hormone responsive and c-erb-B2 negative comprised of 36% of cases. The portions of patients with visceral metastases, cranial metastases, and 2 or more organ involvement were 82%, 24%, and 65%, respectively. Subjects had received this treatment in the fourth or more advanced setting in 50% of cases (after a median of 2.5 cycles). The median overall and progression free survival figures were 25 and 10.5 months, respectively. No toxic mortality occurred, and the treatment was well tolerated. Toxicity and response data are being updated currently. Conclusions: Semi-metronomic treatment with metronomic cyclophosphomide and oral etoposide is a novel and effective strategy in heavily pretreated MBC patients. Survival data and low cost may make this regimen a highly preferable option in this difficult patient group. No significant financial relationships to disclose.