Stratification with respect to hormone receptor and HER 2/neu in the treatment of metastatic breast cancer; sensitivity to taxane

• Published in: Gan to kagaku ryoho Vol. 34; no. 1; p. 53
• Main Authors: Kan, Norimichi, Mise, Keiichi, Moriguchi, Yoshio, Kodama, Hiroshi
• Format: Journal Article
• Language: Japanese
• Published: Japan 01.01.2007
• Subjects: Antibodies, Monoclonal - administration & dosage; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Breast Neoplasms - chemistry; Breast Neoplasms - drug therapy; Breast Neoplasms - mortality; Breast Neoplasms - pathology; Bridged-Ring Compounds - administration & dosage; Female; Humans; Liver Neoplasms - secondary; Pleural Effusion, Malignant - etiology; Receptor, ErbB-2 - analysis; Receptors, Estrogen - analysis; Receptors, Progesterone - analysis; Retrospective Studies; Survival Rate; Taxoids - administration & dosage; Trastuzumab
• ISSN: 0385-0684

Of 231 patients with recurrent or metastatic breast cancer treated in Hiei Hospital between January 2001 and March 2005, for whom data on hormone receptor (HR) and HER 2/neu were available, we retrospectively analyzed the association of the response rate with HR and HER 2 in 172 patients treated with taxane in whom the treatment response could be evaluated. Among the patients treated with taxane alone,the response rates were 37.5% (n=67) in the HR (+) patients and 14.6% (n=41) in the HR (-) patients (p=0.0131). In particular, taxane resistance was suggested in the HR (-)/HER 2 (-) patients (response rate: 4.2%, n=24). Concerning combination therapy with trastuzumab and taxane, the response rate were 52.8% in the HR (+)/HER 2 (+) patients and 60.4% in the HR (-)/HER 2 (+) patients. In 27 of these patients, single therapy with taxane was switched to combination therapy with taxane and trastuzumab after they became resistant to taxane, and 8.3% of the HR (+)/HER 2 (+) patients and 53.3% of the HR (-)/HER 2 (+) patients responded to this combination therapy (p=0.0192), suggesting the synergistic effects of the two agents in HR (-)/HER 2 (+) patients. Therefore, HR and HER 2 were associated with the sensitivity to a chemotherapeutic agent, taxane. Stratification with respect to HR and HER 2 is important in the treatment of metastatic breast cancer. In particular, therapeutic strategies for HR (-)/HER 2 (-) patients with a poor prognosis must be established in the future.