Objective: To define the prognosis for and radiographic presentation of patients with pulmonary amyloidosis.
Design: Retrospective review of the Mayo Clinic experience with biopsy-proven pulmonary amyloidosis from 1980 to 1993.
Setting: Tertiary care center.
Patients: Patients with pulmonary biopsy specimens showing amyloid deposition.
Measurements: Medical records were reviewed, and pertinent information was recorded, including demographic data, type of pulmonary biopsy, results of biopsies of nonpulmonary sites and of immunoelectrophoresis, and other clinical, radiographic, and laboratory information necessary for distinguishing localized pulmonary amyloidosis, primary systemic amyloidosis, secondary amyloidosis, and familial amyloidosis.
Results: 35 of 55 patients with pulmonary amyloidosis had primary systemic amyloidosis that presented radiographically as an interstitial or reticulonodular pattern with or without pleural effusion. The median survival after diagnosis was 16 months. Nodular pulmonary "amyloidomas" (nodular amyloid lesions) were not associated with systemic disease and were associated with a benign prognosis. Three of 4 patients with localized tracheobronchial amyloidosis required Nd:YAG (neodymium:yttrium-aluminum-garnet) laser therapy for obstructive symptoms. "Senile" amyloid deposition was an incidental finding in some patients at autopsy.
Conclusions: Localized amyloidomas are characterized by a benign course and are not associated with systemic amyloidosis. Despite its localized nature, tracheobronchial amyloid deposition may be asymptomatic or may result in significant morbidity due to obstructive phenomena. Pulmonary amyloidosis associated with primary systemic amyloidosis generally presents as a diffuse interstitial pattern with or without pleural effusion. Complete survival data indicate that long-term outcome is poor after diagnosis. We describe the largest series of patients diagnosed by bronchoscopic lung biopsy. Despite reports to the contrary, we have found bronchoscopic lung biopsy to be a safe and effective diagnostic technique.