Multifocal Micronodular Pneumocyte Hyperplasia: Computed Tomographic Appearance and Follow-Up in Tuberous Sclerosis Complex

Objective: To characterize pulmonary nodules in patients with tuberous sclerosis complex (TSC) using computed tomography. Methods: We retrospectively reviewed chest computed tomographic images of 73 patients with TSC (22 males and 51 females; mean +/- SD age, 31.5 +/- 13.2 years; range, 13.8-63.5 years). Results: Multiple pulmonary nodules were identified in 42 (58%) of 73 patients (mean T SD size, 6.6 +/- 3.0 mm; range, 2-14 mm). Solid nodules were present in 11 (26%) of 42 patients, ground-glass nodules were present in 3 (7%) of 42 patients, and both solid and ground-glass nodules were present in 28 (67%) of 42 patients. The presence of multiple nodules was independent of sex and lymphangioleiomyomatosis. Follow-up images were available for 22 patients with multiple nodules (mean T SD follow-up, 2.0 +/- 1.1 years; range, 0.9-4.9 years), none of whom had change in nodule size or number. Conclusions: Most men and women with TSC have multiple pulmonary nodules, which likely represent multifocal micronodular pneumocyte hyperplasia in the absence of known predisposing factors.