The presentation, treatment, and outcome of 28 patients with aspergilloma and cavitary tuberculosis (14) and sarcoidosis (14) were compared. Patients with tuberculosis had localized disease (12 of 14, 86 percent), whereas patients with sarcoidosis had diffuse disease (1 of 14, 7 percent localized). Results indicated that patients with either sarcoid or tuberculosis who developed an aspergilloma had a poor prognosis over the next decade. Patients with sarcoid appeared to have a worse short-term prognosis; surgical resection in the tuberculosis patients may have contributed to their better short-term survival.