Weekly administration of bendamustine as salvage therapy in metastatic breast cancer: final results of a phase II study.
Single-agent bendamustine has shown promise in the treatment of metastatic breast cancer. As toxicity was low after weekly administration of this drug in other solid tumors, the present double-center phase II trial was conducted to evaluate the efficacy and toxicity of weekly bendamustine as salvage treatment in metastatic breast cancer. A total of 34 patients with anthracycline (88%) and/or taxane (71%) pretreated for metastatic breast cancer received 60 mg/m bendamustine on day 1, 8 and 15 every 28 days for six cycles. In addition, 10 patients with HER2/neu-overexpressing tumors either continued (five patients) or started treatment with 2 mg/kg trastuzumab weekly (loading dose 4 mg/kg) at study entry. Patients had predominantly visceral disease and had received one (88%) or two chemotherapy regimens for metastatic breast cancer. All patients were eligible for toxicity and 27 for response evaluation. No grade 3 or 4 hematologic toxicity occurred. Only three patients experienced grade 3 nonhematologic toxicity. Five patients (19%) reached a partial response. Stable disease for at least 6 months was achieved in eight patients, for a clinical benefit rate of 48%. The median progression-free survival and median overall survival were 6 months (range, 1-16) and 15 months (range, 2-28), respectively. We conclude that weekly bendamustine is a valid treatment option in patients with anthracycline-pretreated and/or taxanepretreated metastatic breast cancer; in particular, due to its low toxicity profile. Future trials should evaluate higher single doses of bendamustine in a weekly schedule.
Department of Gynecology and Obstetrics, University of Heidelberg Medical School, Heidelberg, Germany. Michael_Eichbaum@med.uni-heidelberg.de
Michael H R
MH
Eichbaum
Florian
F
Schuetz
Tanja
T
Khbeis
Ilka
I
Lauschner
Frank
F
Foerster
Christof
C
Sohn
Andreas
A
Schneeweiss
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000069461:Bendamustine Hydrochloride; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D018734:Genes, erbB-2 / Q000235:genetics; D006402:Hematologic Diseases / Q000139:chemically induced / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009588:Nitrogen Mustard Compounds / Q000009:adverse effects / Q000627:therapeutic use*; D016879:Salvage Therapy; D016019:Survival Analysis
D000970:Antineoplastic Agents; D009588:Nitrogen Mustard Compounds; D000069461:Bendamustine Hydrochloride