['To evaluate the 5-year prognosis of patients with stage I and stage II newly detected (< 3 months) pulmonary sarcoidosis treated immediately after diagnosis with prednisolone for 3 months followed by inhaled budesonide for 15 months.', 'Randomized, double-blind, placebo-controlled, parallel-group study for 18 months. Thereafter, open follow-up without treatment.', 'Twenty pulmonary medicine departments in Finland.', 'One hundred eighty-nine adult patients, most of them with normal lung function, were randomized to treatment. One hundred forty-nine patients were followed up for 5 years: 79 patients with initial stage I disease and 70 patients with stage II disease.', 'Oral prednisolone for 3 months followed by inhaled budesonide for 15 months (800 microg bid), or placebo tablets followed by placebo inhaler therapy. Thereafter, treatment only on an individual basis in the case of clinical deterioration.', 'Yearly follow-up visits with chest radiographs, lung function tests (FEV(1), FVC), diffusion capacity of the lung for carbon monoxide (DLCO), serum angiotensin-converting enzyme (SACE), and serum and urinary calcium measurements.', 'No initial differences were observed in chest radiographic findings between the active-treatment and placebo-treatment groups, either in patients with initial stage I or stage II(-III) disease. However, after the 5-year follow-up, 18 steroid-treated patients (26%) and 30 placebo-treated patients (38%) still had remaining chest radiographic changes. Placebo-treated patients more frequently required treatment with corticosteroids during the 5-year follow-up (p < 0.05). Steroid-treated patients with initial stage II(-III) disease improved more in FVC and DLCO (p < 0.05). No differences in reported adverse events or in SACE, serum calcium, or urinary calcium values were seen.'] Does early treatment of stage II sarcoidosis improve 5-year pulmonary function?