CBDCA + Pemetrexed + Bevacizumab and Its Maintenance Chemotherapy in a Case of Solitary Breast Metastasis from a Lung Adenocarcinoma Resistant to Gefitinib

Based on the AVAPERL trial (36th ESMO 2011), CBDCA + pemetrexed + bevacizumab and its maintenance chemotherapy with pemetrexed + bevacizumab is a new promising regimen for the treatment of advanced non-small-cell lung adenocarcinoma. Herein, we report the rare case of a patient with solitary breast metastasis from a lung adenocarcinoma, which was effectively treated using CBDCA + pemetrexed + bevacizumab and its maintenance chemotherapy. A 57-year-old female was admitted to the hospital due to pleural effusion and cardiac tamponade caused by a lung adenocarcinoma possessing a mutation of the epidermal growth factor receptor (EGFR) gene (deletion of exon 19). The patient was treated by first-line chemotherapy (gefitinib 250 mg/body/day) which resulted in complete response. After 12 months, carcinoembryonic antigen was gradually increasing and she complained of a right breast mass. With a core-needle biopsy, the breast tumor was pathologically diagnosed as recurrence and solitary metastasis of a lung adenocarcinoma. Further study of the second mutation of EGFR revealed a T790M mutation. The patient was treated by second-line chemotherapy [CBDCA + pemetrexed + bevacizumab (AUC 6 + 500 mg/m(2) + 15 mg/kg)] and its maintenance chemotherapy (pemetrexed + bevacizumab). The cases of patients with breast metastasis from other organs are very rare. Immunohistopathological analysis is very useful to diagnose whether the malignancy is primary or not. In the case of a breast tumor with present or previous malignancy, a metastatic breast tumor should be considered. Furthermore, the biopsy of the breast metastasis also revealed the second mutation of resistance to gefitinib, T790M. Of note, according to our case, CBDCA + pemetrexed + bevacizumab and its maintenance chemotherapy is feasible and well tolerated for breast metastasis from a lung adenocarcinoma which is resistant to gefitinib and possesses the T790M mutation in the EGFR gene.