An 83-year-old man was found to have multiple pulmonary nodules and ground-glass opacities after a left upper lobectomy for non-small-cell lung cancer. After bronchoalveolar lavage and transbronchial lung biopsy, he was put on a regimen of steroids for a tentative diagnosis of organizing pneumonia. Over the course of 3 months, the radiographic findings improved; however, they progressively deteriorated during the steroid tapering period and new skin lesions also appeared. Skin biopsy specimens showed lymphohistiocytic infiltration in which the atypical lymphocytes were positive for EBV encoding small RNAs by in situ hybridization; we therefore diagnosed lymphomatoid granulomatosis. The pulmonary and cutaneous lesions responded to steroid and cyclophosphamide therapy, but the patient died unexpectedly due to a rapid onset of massive pulmonary thromboembolism.