Amyloid-associated cystic lung disease

BACKGROUND: Amyloid-associated cystic lung disease is rare. It can be associated with collagen vascular disease (CVD). We aimed to describe the clinical, radiology, and pathology findings of this entity. METHODS: We reviewed the records of subjects having biopsy-proven pulmonary amyloidosis with cystic lung disease demonstrated at high-resolution computed tomography (HRCT). Demographic characteristics, association with CVD and lymphoproliferative disorders, pulmonary function, and pathology results were reviewed. HRCT appearance was analyzed for number, size, distribution, and morphology of cysts and nodules. RESULTS: Twenty-one subjects (13 female, eight male; median age, 61 years) with cystic pulmonary amyloidosis were identified. The most common pulmonary function patterns were normal (42%) and obstructive (32%). The most common associated CVD was Sjögren syndrome (10 of 12). Nine subjects had no CVD. Cysts tended to be multiple ($ 10 in 14 of 21, 67%), round (21 of 21, 100%), or lobulated (20 of 21, 95%); thin-walled (< 2 mm in 17 of 21, 81%); and of small (< 1 cm in 21 of 21, 100%) to moderate (1-2 cm in 17 of 21, 81%) size. Peribronchovascular (19 of 21, 90%) and subpleural (19 of 21, 90%) cysts were typically present. Seventeen (81%) subjects had lung nodules, which tended to be numerous ($ 10 in 10 of 17, 59%; 4-9 in six of 17, 35%). At least one calcified nodule was present in 14 of 17 subjects (82%). Pulmonary mucosa-associated lymphoid tissue lymphoma (MALToma) was diagnosed in seven subjects (33%). CONCLUSIONS: Amyloid-associated cystic lung disease can occur with or without underlying CVD. Cystic lesions in the lung are commonly numerous, often are peribronchovascular or subpleural, and are frequently associated with nodular lesions that are often calcified. MALToma was a relatively frequent association.