Incidental pulmonary emboli are present in a small percentage of oncology patients but are frequently missed on initial CT interpretation due to the small size of involved arteries.
Incidental pulmonary emboli were seen in 16 (4%) oncology patients but were initially reported in only four of them. The small size of involved arteries contributes to the failed detection at initial CT image interpretation, and patients with emboli in these small vessels may have deep vein thrombosis or recurrent emboli.
Gladish et al. (2006) studied this question.