Clinically unsuspected pulmonary embolism—an important secondary finding in oncology CT

doi:10.1016/j.crad.2005.09.002

Clinical Radiology

Volume 61, Issue 1, January 2006, Pages 81-85

https://doi.org/10.1016/j.crad.2005.09.002 Get rights and content

AIM

To determine the rate of finding incidental pulmonary embolisms (PE) at staging or follow-up chest computed tomography (CT) in oncology patients.

MATERIALS AND METHODS

Three hundred and eighty-five consecutive chest CT examinations, performed in patients with cancer, were prospectively assessed during a 9-month period between October 2003 and June 2004. These were spiral acquisitions between 5 and 8 mm collimation acquired 25 s after intravenous contrast medium administration. PE was diagnosed if a filling defect was seen in the central pulmonary arteries on two or more consecutive slices.

RESULTS

Ten of 385 (2.6%) of these patients had incidentally detected PE. This was not attributable to any specific malignancy or chemotherapeutic regimen. These emboli were all central, between the main pulmonary artery and the lobar level. Although the significance of these findings in patients not clinically suspected of having PE could be contentious, all the patients were started on therapeutic anticoagulation as a result of this observation.

CONCLUSION

Over one in 40 oncology patients have incidental central PE visible on the CT images performed to assess their malignancy. Formal review of the pulmonary arteries, using a work station, is advised in patients with malignancy.

Introduction

There is an increased risk of pulmonary embolism (PE) in patients with malignancy. This increased risk is four-fold above the general population and increases to six-fold if the patient is receiving chemotherapy.¹ PE rates of between 1 and 43% have been reported depending on the tumour type, stage and chemotherapeutic regimen.² A significant proportion of patients with PE will have a non-specific presentation³ or will be asymptomatic.⁴ Incidental PE is occasionally detected in our centre during staging or follow-up computed tomography (CT) examinations of oncology patients. A prospective study was undertaken to determine the rate of this finding in our institution and compare this with rates described in the literature.

Section snippets

Materials and methods

Three hundred and eighty-five consecutive chest CT examinations in patients with malignancy were prospectively evaluated by a single consultant radiologist as part of the standard reporting of these CT images. This radiologist had 2 years experience as a consultant reporting mainly oncology CT. The cases occurred over a 9-month period from October 2003 to June 2004. Review of the pulmonary arteries is standard practice for evaluation of these images,5, 6 and the reporting process was not

Results

Of the 385 patients studied, 51% (196/385) were males and 49% (189/385) were females. The average patient age was 61 years (range 22–94 years). Ten patients had visible PE on their CT images. In nine of these PE had not been observed before, this being the first time PE had been diagnosed for the patient. In one (patient 2) PE had been incidentally noted on a staging CT examination 8 weeks earlier, but as the observation at that time was also entirely incidental, it was felt valid to include

Discussion

Cancer patients often undergo multiple CT investigations as part of their cancer staging and treatment monitoring. Review of the pulmonary arterial tree on these examinations will reveal PE in a small, but potentially clinically significant, percentage of cases. The best method of visualization is clearly at the work station using windowing specifically tailored to the pulmonary vascular tree in question. Conventional soft-tissue windows often do not show the pulmonary arteries well as the

References (14)

J.A. Heit et al.
Risk factors for deep vein thrombosis and pulmonary embolism: a population based case–control study
Arch Intern Med
(2000)
A.Y.Y. Lee et al.
Venous thromboembolism and cancer: risks and outcomes
Circulation
(2003)
W.J. Fulkerson et al.
Diagnosis of pulmonary embolism
Arch Intern Med
(1986)
J.W. Williams et al.
Asymptomatic pulmonary embolism: a common event in high-risk patient
Ann Surg
(1982)
C.B. Winston et al.
Incidental pulmonary emboli detected at helical CT: effect on patient care
Radiology
(1996)
M.V. Gosselin et al.
Unsuspected pulmonary embolism: prospective detection on routine helical CT scans
Radiology
(1998)
M.A. Whittle et al.
The role of spiral computed tomography pulmonary angiography in the investigation of pulmonary embolism
Imaging
(1998)

There are more references available in the full text version of this article.

Cited by (76)

The association between cancer diagnosis, care, and outcomes in 1 million patients hospitalized for acute pulmonary embolism
2023, International Journal of Cardiology
To evaluate the clinical care provided to cancer patients hospitalized for acute pulmonary embolism (PE), as well as the association between type of cancer, in-hospital care, and clinical outcomes.
This study examined the in-hospital care (systemic thrombolysis, catheter-directed thrombolysis, and surgical thrombectomy/embolectomy) and clinical outcomes (mortality, major bleeding, and hemorrhagic stroke) among adults hospitalized due to acute PE between October 2015 to December 2018 using the National Inpatient Sample (NIS). Multivariable logistic regression analysis was used to determine adjusted odds ratios (aOR) with 95% confidence interval (95% CI).
Of 1,090,130 hospital records included in the analysis, 216,825 (19.9%) had current cancer diagnoses, including lung (4.7%), hematological (2.5%), colorectal (1.6%), breast (1.3%), prostate (0.8%), and ‘other’ cancer (9.0%). Cancer patients had lower adjusted odds of receiving systemic thrombolysis, catheter-directed therapy, and surgical thrombectomy/embolectomy compared with their non-cancer counterparts (P < 0.001), except for systemic thrombolysis (aOR 0.96, 95% CI 0.85–1.09, P = 0.553) and catheter-directed therapy (aOR 0.82, 95% CI 0.67–1.00, P = 0.053) for prostate cancer. Cancer patients had greater odds of mortality (P < 0.05). Lung cancer patients had the highest odds of mortality (aOR 2.68, 95% CI 2.61–2.76, P < 0.001) and hemorrhagic stroke (aOR 1.75, 95% CI 1.61–1.90, P < 0.001), while colorectal cancer patients had the greatest odds of bleeding (aOR 2.04, 95% CI 1.94–2.15, P < 0.001).
Among those hospitalized for PE, cancer diagnoses were associated with lower odds of invasive management and poorer in-hospital outcomes, with metastatic status being an especially important determinant. Appropriateness of care could not be assessed in this study.
The prognostic value of respiratory symptoms and performance status in ambulatory cancer patients and unsuspected pulmonary embolism; analysis of an international, prospective, observational cohort study
2021, Journal of Thrombosis and Haemostasis
Optimal risk stratification of unsuspected pulmonary embolism (UPE) in ambulatory cancer patients (ACPs) remains unclear. Existing clinical predictive rules (CPRs) are derived from retrospective databases and have limitations. The UPE registry is a prospective international registry with pre‐specified characteristics of ACPs with a recent UPE. The aim of this study was to assess the utility of risk factors captured in the UPE registry in predicting proximate (30‐, 90‐ and 180‐day) mortality and how they performed when applied to an existing CPR.
To evaluate risk factors for proximate mortality, overall survival, recurrent venous thromboembolism and major bleeding, in the patients enrolled in the UPE registry cohort.
Data from the 695 ACPs in this registry were subjected to multivariate logistic regression analyses to identify predictors independently associated with proximate mortality and overall survival. The most consistent predictors were applied to the Hull CPR, an existing 5‐point prediction rule.
The most consistent predictors of mortality were patient‐reported respiratory symptoms within 14 days before, and ECOG performance status at the time of UPE. These predictors applied to the Hull‐CPR produced a consistent correlation with proximate mortality and overall survival (area under the curve [AUC] = 0.70 [95% CI 0.63, 077], AUC = 0.65 [95% CI 0.60, 070], AUC = 0.64 [95% CI 0.59, 068], and AUC = 0.61, 95% CI 0.57, 0.65, respectively).
In ACPs with UPE, ECOG performance status logged contemporaneously to the UPE diagnosis and respiratory symptoms prior to UPE diagnosis can stratify mortality risk. When applied to the HULL‐CPR these risk predictors confirmed the risk stratification clusters of low‐intermediate and high‐risk for proximate mortality as seen in the original derivation cohort.
Management of cancer-related thrombosis in the era of direct oral anticoagulants: A comprehensive review of the 2019 ITAC-CME clinical practice guidelines. On behalf of the Groupe Francophone Thrombose et Cancer (GFTC)
2020, JMV-Journal de Medecine Vasculaire
Citation Excerpt :
This is likely related to several factors, including the thrombogenic potential of newer chemotherapy regimens [23], increased patient survival, and the aging cancer patient population. More efficient detection of both symptomatic and asymptomatic VTE may also be a contributing factor to the increased incidence of VTE, as well as routine repeated computed tomography (CT) scans during follow-up for diagnostic evaluations and staging [2,23,24]. VTE is a preventable cause of inpatient mortality, highlighting the critical need for optimal prophylaxis and treatment in these high-risk patients.
Venous thromboembolism (VTE) is a common disease complication in cancer patients and the second cause of death after cancer progression. VTE management and prophylaxis are critical in cancer patients, but effective therapy can be challenging because these patients are at higher risk of VTE recurrence and bleeding under anticoagulant treatment. Numerous published studies report inconsistent implementation of existing evidence-based clinical practice guidelines (CPG), including underutilization of thromboprophylaxis, and wide variability in clinical practice patterns across different countries and various practitioners. This review aims to summarize the 2019 ITAC-CME evidence-based CPGs for treatment and prophylaxis of cancer-related VTE, which include recommendations on the use of direct oral anticoagulants specifically in cancer patients. The guidelines underscore the gravity of developing VTE in cancer and recommend the best approaches for treating and preventing cancer-associated VTE, while minimizing unnecessary or over-treatment. Greater adherence to the 2019 ITAC guidelines could substantially decrease the burden of VTE and improve survival of cancer patients.
Radiographer screening for incidental pulmonary emboli on routine contrast-enhanced computerised tomography scans at a cancer centre
2018, Clinical Radiology
Citation Excerpt :
The incidence of pulmonary emboli is four- to six-times greater in an oncology population than the general medical population,1 and the diagnosis of an incidental pulmonary embolus is associated with the same adverse survival in cancer patients as in patients with symptomatic pulmonary emboli.2
To introduce and assess effectiveness of a radiographer-led screening programme for the detection of unsuspected pulmonary emboli on routine contrast-enhanced computed tomography (CT), and to evaluate radiographer response to this extended role.
A training programme was devised for all radiographic staff working in CT. The screening service was introduced and monthly quality assurance performed with cumulative analysis of the first 2 years. Clinical effectiveness before and after screening was evaluated by comparing the time interval between the scan and the start of a clinical consultation for anticoagulant prescription. A satisfaction survey was sent to all participating staff.
Thirty-two radiographers completed the training. During the training period, the radiographer detection rate of incidental pulmonary emboli was 89%. Main, lobar, segmental, and subsegmental emboli were detected. The overall detection rate after full introduction of the programme was 92% for the first 2 years. The time interval between the scan and clinical consultation for anticoagulant prescription dropped from a mean of 1.5 days to a mean of 26 minutes and ensured that treatment was commenced at the same patient attendance. Eighty-four percent of staff completed the satisfaction survey and all were satisfied with the extended role.
Radiographer screening for incidental pulmonary emboli was effective and accurate. It resulted in immediate communication with the responsible physician and commencement of anticoagulation therapy at the same hospital attendance, creating a “one-stop” service. Radiographer satisfaction with the extended role was high.
Best Clinical Practice: Current Controversies in Pulmonary Embolism Imaging and Treatment of Subsegmental Thromboembolic Disease
2017, Journal of Emergency Medicine
Pulmonary embolism (PE) affects >600,000 patients per year in the United States. Evaluation includes clinical decision rules, laboratory tests, and several imaging modalities. The diagnosis of PE has risen in recent years, particularly subsegmental PE (SSPE). Controversy exists concerning the diagnosis and treatment of these lesions.
We sought to provide emergency physicians with a review of the controversies surrounding PE testing and the diagnosis and treatment of SSPE.
With the rise of computed tomography (CT) testing for PE, diagnosis has increased. Providers often omit risk stratification in favor of D-dimer or imaging, which does not have literature support. The detection of PE has risen by 80%, and this increased testing is associated with several risks, including contrast reaction, nephropathy, and increased radiation. SSPE diagnosis has risen with improved imaging technology, but the literature shows low interobserver agreement with diagnosis of true SSPE. Studies disagree on the clinical significance and dangers of this PE subset. The American College of Chest Physicians 2016 guidelines recommend withholding anticoagulation for SSPE with low risk for recurrent thrombus and no concurrent deep vein thrombosis. Patients at high risk for recurrent venous thromboembolism or with deep vein thrombosis warrant anticoagulation. The provider is ultimately responsible for appropriate evaluation with risk stratification and selective testing.
SSPE presents a quandary, because the literature differs in showing harm despite increased diagnosis. American College of Chest Physicians guidelines for the treatment of SSPE take into account the patient, the imaging, and other imaging modalities. Providers should use risk stratification with shared decision-making in the evaluation and treatment of SSPE.
Frequency of Deep Vein Thrombosis and/or Pulmonary Embolism After Coronary Artery Bypass Grafting Investigation Regardless of Clinical Suspicion
2017, American Journal of Cardiology
Venous thromboembolism (VTE) includes deep vein thrombosis (DVT) and/or pulmonary embolism (PE). Many surgeons and clinicians believe that VTE after coronary artery bypass grafting (CABG) has little clinical significance because it is seldom diagnosed. This study aimed to identify VTE after CABG, independent of clinical suspicion. In this prospective, observational, single-center study, 100 patients underwent computed tomographic pulmonary angiography (multidetector-64) and lower extremity venous compressive ultrasound after elective CABG. Patients with high risk for VTE were excluded. Aspirin was maintained throughout the preoperative and postoperative periods, and early ambulation was encouraged. Postoperatively, no mechanical or heparin prophylaxis was used in any patients. At the discretion of the surgeons, 83 surgeries were on-pump, and 17 were off-pump. On average, tomography and ultrasound were performed 7 ± 3 days after CABG. Isolated PE was observed in 13 of 100 patients (13%), simultaneous PE and DVT in 8 of 100 (8%), and isolated DVT in 4 of 100 (4%), thus totaling 25/100 VTEs (25%). Of the 21 PEs, 3 of 21 (14%) involved subsegmental, 15 of 21 (71%) segmental, 1 of 21 (5%) lobar, and 2 of 21 (10%) central pulmonary arteries. Of the 12 DVTs, all were distal (below the popliteal vein), and 2 of 12 (17%) were also proximal; 5 of 12 (42%) were unilateral, of which 3 of 5 (60%) on the contralateral saphenous vein-harvested leg. No VTE caused hemodynamic instability, and none was clinically suspected. In conclusion, VTEs were frequent, some extensive proximal VTEs occurred, but most were distally localized. Many patients in this series would have been discharged without diagnosis of and treatment for PE and/or DVT.

View all citing articles on Scopus

^{^†}: Guarantor: A.J. Paddon.

View full text

Clinically unsuspected pulmonary embolism—an important secondary finding in oncology CT

AIM

MATERIALS AND METHODS

RESULTS

CONCLUSION

Introduction

Section snippets

Materials and methods

Results

Discussion

Risk factors for deep vein thrombosis and pulmonary embolism: a population based case–control study

Arch Intern Med

Venous thromboembolism and cancer: risks and outcomes

Circulation

Diagnosis of pulmonary embolism

Arch Intern Med

Asymptomatic pulmonary embolism: a common event in high-risk patient

Ann Surg

Incidental pulmonary emboli detected at helical CT: effect on patient care

Radiology

Unsuspected pulmonary embolism: prospective detection on routine helical CT scans

Radiology

The role of spiral computed tomography pulmonary angiography in the investigation of pulmonary embolism

Imaging