November 2016 pulmonary case of the month

No abstract available. Article truncated after 150 words. History of Present Illness: Our patient is a 76-year-old gentleman who was referred based on an abnormal CT scan. He has a history of metastatic melanoma and had begun immunotherapy with pembrolizumab 10 months prior to admission. He had low grade fevers and chills and some dyspnea on exertion and dry cough. He also had a 6-8 pound weight loss over 4 weeks. PMH, SH and FH: He has a history of hairy cell leukemia since 2009; squamous and basal cell cancers; and diabetes on insulin. He is a retired commercial banker and has a 15 pack-year smoking history. Physical Examination: Physical examination showed and SpO2 of 90% on room air. His lungs were clear. He had numerous depigmented lesions on his skin. Radiography: A thoracic CT scan was performed (Figure 1) and compared to a scan done 3 months prior which was considered unremarkable. Which of the following best ...