Small pulmonary nodules of soft tissue density are often found during
computed tomography for the staging of lung cancer, but CT cannot reli
ably distinguish benign from malignant uncalcified pulmonary nodules.
The purpose of this study was to assess the significance of pulmonary
nodules discovered on staging CT. 551 patients with lung cancer who ha
d a staging CT and who were considered operable were studied. Eighty-e
ight patients (16%) were found to have small non-calcified pulmonary n
odules. Adequate follow-up was possible in 25 patients who had a total
of 36 nodules. Twenty-five nodules (70%) were subsequently confirmed
to be benign, four (11%) were malignant and the nature of seven (19%)
could not be determined. The high prevalence of benign nodules in this
population should be taken into account when staging lung cancer.