A retrospective study of 48 patients with non-Hodgkin lymphoma (NHL) who underwent 54 computed tomographic (CT) examinations of the chest evaluated the role of chest CT in the management of this disease. Of 18 cases in which chest radiographs were not indicative of NHL, CT scans showed abnormalities consistent with NHL in five (28%). Of 11 cases where radiographs were questionable, CT confirmed NHL in five (45%) and excluded it in six (55%). Of 25 cases where radiographs were consistent with NHL, CT confirmed the findings in 23 (92%) and added information in all 25. Chest CT affected management in eight of 25 treated and five of 19 untreated patients. It appears to be useful in untreated patients with stage I or II NHL but no definite radiographic abnormalities, or with abnormal radiographs but no extrathoracic spread, and in treated patients with questionable radiographs. CT is not helpful in untreated patients with stage III or IV NHL or treated patients with normal radiographs.