Treatment with everolimus for a patient with systemic metastatic breast cancer results in severe pulmonary injury: a case report.

Everolimus has been used in patients with hormone receptor-positive breast cancer. This study reports that treatment with everolimus alone induced severe pulmonary injury in a patient with systemic metastatic breast cancer. A 58-yearold woman with systemic metastatic breast cancer was treated with everolimus alone for 4 weeks and developed severe cough and dyspnea. Computed tomography (CT) scan of the chest showed a progressive lung tumor accompanied by bilateral pulmonary homogeneous ground-glass opacity, especially in the inferior lobe of the left lung. Laboratory examinations revealed a high frequency of monocytes, higher levels of serum alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and C-reactive protein as well as mild hypoxemia and hypocarbia. However, she had no evidence of infection with mycoplasma pneumoniae, chlamydia, pneumocystis, tuberculosis, influenza A virus, and was negative for serum galactomannan (GM) antigen assay. She was suspected to have drug-induced interstitial pneumonia. Everolimus treatment was stopped, and treated with methylprednisolone and empiric antibiotic therapy for 7 days. She received further corticosteroid treatment and felt much better, accompanied by clearance of lung inflammation; she was discharged from hospital. Our experience suggests that treatment with everolimus alone may cause severe pulmonary injury and should be considered carefully in cases of patients with systemic metastatic breast cancer.