Trastuzumab and vinorelbine (TV) in early stages of breast cancer

Abstract

e11556 Background: HER-2+ breast cancers (BCs) have a higher relapse rate, even for early stages of disease. The combination of trastuzumab and vinorelbine (TV) displays a high degree of synergism both preclinically and in metastatic BC patients that typically tolerate TV remarkably well. Occasionally, patients refuse standard treatment with chemotherapy and trastuzumab because of toxic side effects. In our institution, some of these patients accepted to receive treatment with TV. Methods: We retrospectively collected data on patients with stage I-III BCs, treated with TV as the only chemotherapy regimen. Most patients received TV on a weekly basis (one week off for V every 3–4 weeks) for ∼6 months, followed by 6 more months of T only. Results: Between May 2003 and June 2008, 23 patients were started on weekly TV. Median age was 66. Five patients received TV as preoperative treatment for BCs with the following clinical stages: IIB (1); IIIA (1); IIIB (3). The other 18 patients were pathologically staged as: stage I (11); IIA (5); IIIB (2). All cancers were HER2+; 65% of patients also received hormonal treatment for ER/PR+ disease. 3 patients had been previously treated for BC, and received TV as “adjuvant” treatment after a local relapse. Only one of these patients had previously received chemotherapy, while none had received prior T. No pathological complete response was found at surgery after preoperative TV. TV was very well tolerated, with one patient developing febrile neutropenia, 4 patients grade 3–4 uncomplicated neutropenia, and no other grade 3–4 events. During therapy, 5 patients had an asymptomatic 10–20% drop in the LVEF (Grade 1). Follow-up MUGA scans at 1 year after TV so far failed to show any significant abnormality. At an average follow-up of 26 months, one patient died for non-BC related causes, and all the other 22 patients are disease-free. Conclusions: TV is safe and very well tolerated, with no significant cardiac toxicity in our patient population. Preliminary follow-up data suggest that TV may be an acceptable alternative (neo-)adjuvant therapy for patients refusing “toxic” chemotherapy. Further studies prospectively testing TV as adjuvant treatment should be considered for patients with stage 1A BC, for which no standard treatment is clearly defined. No significant financial relationships to disclose.