Unsuspected pulmonary emboli in cancer patients: clinical correlates and relevance

Advances in computed tomography (CT) scanning have led to the detection of unsuspected pulmonary emboli (PE) on routine cancer staging scans. We hypothesized that these patients had signs or symptoms suggestive of PE that may have been overlooked by their health care providers.

A retrospective chart review was performed on 59 patients found on routine cancer staging CT scans to have unsuspected PE. Information on patient demographics, malignancy characteristics, risk factors for venous thromboembolism (VTE), and symptoms was recorded. A retrospective case-control analysis was then performed using two age- and stage-matched control patients for each patient who had similar staging CT scans performed during the same period.

Fifty-two patients with unsuspected PE were identified. Forty-four percent had signs or symptoms commonly associated with PE; when fatigue was included, 75% were symptomatic. Ninety-two control patients were identified for 46 of the case patients. Patients with unsuspected PE were significantly more likely to have had a prior history of VTE (20% v 3%; P = .007). The patients with PE were significantly more likely than control patients to complain of fatigue (54% v 20%; P = .0002) and shortness of breath (22% v 8%; P = .02). There was no difference between the groups in administration of chemotherapy within 30 days, central venous catheter use, or erythropoietin therapy.

Seventy-five percent of patients found to have unsuspected PE on cancer staging CT scans were symptomatic. Fatigue and shortness of breath were significantly more common in patients with unsuspected PE than in control patients.