Pulmonary infiltrates in a patient with advanced melanoma

A 60-year-old former smoker with metastatic melanoma presented with the chief complaint of pulmonary infiltrates. Five years ago, he was diagnosed with a left chest wall melanoma. He underwent surgery but received no additional therapy for an American Joint Committee on Cancer stage T3a N0 M0 tumor that was 2.7 mm in depth with no ulceration of the epidermal surface. Resection margins were free of tumor. Four years later, he underwent excision of a raised pigmented skin lesion on his left calf that proved to be melanoma with positive margins. He underwent re-excision of melanoma but 2 months later developed a new left hip soft tissue nodule. Positron emission tomography (PET) - computed tomography showed multiple hypermetabolic lesions involving subcutaneous tissue, muscle osseous structures, and bone marrow, consistent with advanced melanoma. He began systemic therapy with ipilimumab and nivolumab. After four cycles of immunotherapy, he developed a nonproductive cough and mild dyspnea on exertion (Modified Medical Research Council dyspnea scale score of 2 [ie, he had to stop for breath when walking at his own pace on level ground]). A chest x-ray showed bilateral hilar enlargement, thickening of the right paratracheal stripe, and scattered patchy increased interstitial markings bilaterally. PET and chest computed tomography images showed enlarged mediastinal adenopathy with increased [¹⁸F]fluorodeoxyglucose uptake on PET and scattered diffuse 1- to 2-mm pulmonary nodules with ground-glass opacities (Fig 1). The patient was referred for pulmonary input. The patient had smoked one pack of cigarettes per day for 35 years; he quit 6 years ago. He had no history of pneumonia, childhood asthma, or tuberculosis. His mother had asthma, but there was no other family history of asthma or other lung disease.