Granuloma-forming interstitial pneumonia occurring one year after the start of everolimus therapy.

We experienced a case of interstitial lung disease (ILD) that occurred one year after the start of everolimus therapy for renal cell carcinoma. The pathological features included interstitial pneumonia with granuloma formation. Everolimus is known to cause ILD; however, its pathology is unclear. Granuloma-forming interstitial pneumonia associated with everolimus is uncommon, although it may be one of the pathological patterns associated with everolimus-induced ILD. This is a slow-onset case of everolimus-induced ILD in a patient with renal cell carcinoma. Physicians should thus be aware of the potential for the development of ILD at any time during the administration of everolimus therapy.