2017 Volume 57 Issue 2 Pages 113-117
Background. Lung metastasis of breast cancer 20 years after mastectomy with an air space pattern on imaging harboring an epidermal growth factor receptor (EGFR) gene mutation is rare. Case. A 62-year-old female with a surgical history of breast cancer at 42 years of age was referred to our hospital because of a persistent cough. Chest computed tomography (CT) revealed widespread ground-glass attenuation and air space consolidation in both the middle and lower lung fields. A pathological examination of the lung specimen revealed adenocarcinoma, which was positive for an EGFR gene mutation. The patient was treated with gefitinib for 4 weeks, but her CT findings deteriorated. She underwent a re-biopsy and was diagnosed with lung metastasis from breast cancer. On switching to hormonal therapy, her CT findings improved. Conclusions. We encountered a case of lung metastasis of breast cancer with an air space pattern on imaging that harbored an EGFR gene mutation. Physicians should consider not only lung cancer but also lung metastasis in cases with an air space pattern on imaging. Our case reminds us to consider the possibility of breast cancer, especially when there is a history of breast cancer.