Unsuspected pulmonary emboli adversely impact survival in patients with cancer undergoing routine staging multi-row detector computed tomography scanning.

BACKGROUND

While symptomatic venous thromboembolism adversely impacts survival among cancer patients, the outcome of cancer patients with unsuspected pulmonary embolism (UPE) found on routine cancer staging multi-row detector computed tomography (MDCT) scans is unknown.

OBJECTIVE

To determine whether UPE detected on routine staging MDCT scans impacts overall survival among cancer patients.

PATIENTS AND METHODS

We performed a matched cohort study of cancer patients diagnosed with UPE on routine staging scans between May 2003 and August 2006. Two controls (n = 137) were individually matched by age (± 5 years), cancer type and stage for each UPE patient (n = 70). We used Cox's proportional hazard models to compare the mortality between UPE patients and their matched controls.

RESULTS

The hazard ratio (HR) for death among UPE patients was 1.51 (95% CI 1.01-2.27, P = 0.048). Compared with their matched controls, patients with UPE more proximal than the subsegmental arterial branches had a HR for death at 6 months of 2.28 (95% CI 1.20-4.33, P = 0.011) and an overall HR of 1.70 (95% CI 1.06-2.74, P = 0.027). Survival among UPE patients with isolated subsegmental PE (ISSPE) was not significantly different than that of matched controls (HR 1.04 95% CI 0.44-2.39, P = 0.92).

CONCLUSIONS

UPE identified more proximal than the subsegmental arterial branches has a significant negative impact on survival among cancer patients.