Incidental Pulmonary Emboli in Oncology Patients: Prevalence, CT Evaluation, and Natural History

Prospective Evaluation of Artificial Intelligence Triage of Incidental Pulmonary Emboli on Contrast-Enhanced CT Examinations of the Chest or Abdomen

BACKGROUND. Artificial intelligence (AI) algorithms improved detection of incidental pulmonary embolism (IPE) on contrast-enhanced CT (CECT) examinations in retrospective studies; however, prospective validation studies are lacking. OBJECTIVE. The purpose of this study was to assess the effect on radiologists' real-world diagnostic performance and report turnaround times of a radiology department's clinical implementation of an AI triage system for detecting IPE on CECT examinations of the chest or abdomen. METHODS. This prospective single-center study included consecutive adult patients who underwent CECT of the chest or abdomen for reasons other than pulmonary embolism (PE) detection from May 12, 2021, to June 30, 2021 (phase 1), or from September 30, 2021, to December 4, 2021 (phase 2). Before phase 1, the radiology department installed a commercially available AI triage algorithm for IPE detection that automatically processed CT examinations and notified radiologists of positive results through an interactive floating widget. In phase 1, the widget was inactive, and radiologists interpreted examinations without AI assistance. In phase 2, the widget was activated, and radiologists interpreted examinations with AI assistance. A review process involving a panel of radiologists was implemented to establish the reference standard for the presence of IPE. Diagnostic performance and report turnaround times were compared using the Pearson chi-square test and Wilcoxon rank sum test, respectively. RESULTS. Phase 1 included 1467 examinations in 1434 patients (mean age, 53.8 ± 18.5 [SD] years; 753 men, 681 women); phase 2 included 3182 examinations in 2886 patients (mean age, 55.4 ± 18.2 years; 1520 men, 1366 women). The frequency of IPE was 1.4% (20/1467) in phase 1 and 1.6% (52/3182) in phase 2. Radiologists without AI, in comparison to radiologists with AI, showed significantly lower sensitivity (80.0% vs 96.2%, respectively; p = .03), without a significant difference in specificity (99.9% vs 99.9%, p = .58), for the detection of IPE. The mean report turnaround time for IPE-positive examinations was not significantly different between radiologists without AI and radiologists with AI (78.3 vs 74.6 minutes, p = .26). CONCLUSION. An AI triage system improved radiologists' sensitivity for IPE detection on CECT examinations of the chest or abdomen without significant change in report turnaround times. CLINICAL IMPACT. This prospective real-world study supports the use of AI assistance for maximizing IPE detection.

Lung Cancer Related Thrombosis (LCART): Focus on Immune Checkpoint Blockade

Cancer-associated thrombosis (CAT) is a common complication in lung cancer patients. Lung cancer confers an increased risk of thrombosis compared to other solid malignancies across all stages of the disease. Newer treatment agents, including checkpoint immunotherapy and targeted agents, may further increase the risk of CAT. Different risk-assessment models, such as the Khorana Risk Score, and newer approaches that incorporate genetic risk factors have been used in lung cancer patients to evaluate the risk of thrombosis. The management of CAT is based on the results of large prospective trials, which show similar benefits to low-molecular-weight heparins (LMWHs) and direct oral anticoagulants (DOACs) in ambulatory patients. The anticoagulation agent and duration of therapy should be personalized according to lung cancer stage and histology, the presence of driver mutations and use of antineoplastic therapy, including recent curative lung surgery, chemotherapy or immunotherapy. Treatment options should be evaluated in the context of the COVID-19 pandemic, which has been shown to impact the thrombotic risk in cancer patients. This review focuses on the epidemiology, pathophysiology, risk factors, novel predictive scores and management of CAT in patients with active lung cancer, with a focus on immune checkpoint inhibitors.

Comparison of long-term complications in cancer patients with incidental and acute symptomatic venous thromboembolism

Background

Clinical practice guidelines recommend that patients with incidental venous thromboembolism (VTE) receive the same anticoagulant therapy as those with symptomatic VTE. We aimed to compare the rate of complications between cancer patients with incidental and symptomatic VTE through a long-term follow-up cohort.

Methods

We performed a post hoc analysis of prospective studies of cancer patients with VTE between 2008 and 2019, with the primary outcome of rates of recurrent VTE and clinically relevant bleeding (CRB) in incidental and symptomatic VTE groups.

Results

In total, 796 patients were included, of which 42.8% had incidental VTE. No significant differences were noted in the rate of recurrent VTE (0.4 per 100 patients/month vs. 0.5 per 100 patients/month; p = 0.313) and in the rate of CRB (0.6 per 100 patients/month vs. 0.5 per 100 patients/month; p = 0.128) between patients with incidental VTE and symptomatic VTE, respectively. At six-month follow-ups, the cumulative incidence of CRB was significantly higher in patients with incidental VTE than that in those with symptomatic VTE (7.9% vs. 4.4%, respectively; OR: 1.8; 95% CI: 1.01-3.2).

Conclusion

Cancer patients with incidental VTE had similar rates of CRB and VTE recurrence in long-term follow-up compared with patients with symptomatic VTE. At six-month follow-ups, patients with incidental VTE had a higher cumulative incidence of CRB than those with symptomatic VTE.

Characteristic CT angiography findings and clinical value of catheter-related central venous thrombosis in hemodialysis patients with end-stage renal disease

BACKGROUND

Central catheter-related thrombosis (CRT) is the most common catheter-related complication in patients with end-stage renal disease (ESRD) but is often underappreciated and misdiagnosed by radiologist.

PURPOSE

To find the computed tomography angiography (CTA) characteristics of central CRT, then raise the diagnosis of this disorder.

MATERIAL AND METHODS

A total of 301 eligible patients with ESRD who experienced both chest multi-phase multidetector CTA (MDCTA) and digital subtraction angiography were enrolled in the final analysis. The location, shape, and related signs of the central CRT in MDCTA images were evaluated. Independent-samples T test, chi-square test, and binary logistic regression were analyzed using SPSS software.

RESULTS

In total, 166 patients were found to have CRT using MDCTA, and this was verified by DSA. Central CRT was usually irregular in the superior vena cava segment, and the angle of the contact area between central CRT and catheter was <180° (all P < 0.05). Age, collateral circulation, and venous stenosis were shown to have significant differences when compared to patients without CRT (all P < 0.05), but there were no significant differences about the sex or catheter insertion site. In addition, age and collateral circulation were the factors found to be significantly associated with thrombosis (P < 0.05). In particular, the thrombosis was 2.213 times more likely to be found in those patients with collateral circulation (odds ratio = 2.213, 95% confidence interval = 1.236-3.961).

CONCLUSION

Chest multi-phase MDCTA can effectively reduce the missed diagnosis and misdiagnosis of central CRT. It is worth paying more attention to the central CRT especially when the collateral circulation is observed.

Artificial Intelligence Tool for Detection and Worklist Prioritization Reduces Time to Diagnosis of Incidental Pulmonary Embolism at CT

Purpose

To evaluate the diagnostic efficacy of artificial intelligence (AI) software in detecting incidental pulmonary embolism (IPE) at CT and shorten the time to diagnosis with use of radiologist reading worklist prioritization.

Materials and Methods

In this study with historical controls and prospective evaluation, regulatory-cleared AI software was evaluated to prioritize IPE on routine chest CT scans with intravenous contrast agent in adult oncology patients. Diagnostic accuracy metrics were calculated, and temporal end points, including detection and notification times (DNTs), were assessed during three time periods (April 2019 to September 2020): routine workflow without AI, human triage without AI, and worklist prioritization with AI.

Results

In total, 11 736 CT scans in 6447 oncology patients (mean age, 63 years ± 12 [SD]; 3367 men) were included. Prevalence of IPE was 1.3% (51 of 3837 scans), 1.4% (54 of 3920 scans), and 1.0% (38 of 3979 scans) for the respective time periods. The AI software detected 131 true-positive, 12 false-negative, 31 false-positive, and 11 559 true-negative results, achieving 91.6% sensitivity, 99.7% specificity, 99.9% negative predictive value, and 80.9% positive predictive value. During prospective evaluation, AI-based worklist prioritization reduced the median DNT for IPE-positive examinations to 87 minutes (vs routine workflow of 7714 minutes and human triage of 4973 minutes). Radiologists' missed rate of IPE was significantly reduced from 44.8% (47 of 105 scans) without AI to 2.6% (one of 38 scans) when assisted by the AI tool (P < .001).

Conclusion

AI-assisted workflow prioritization of IPE on routine CT scans in oncology patients showed high diagnostic accuracy and significantly shortened the time to diagnosis in a setting with a backlog of examinations.Keywords: CT, Computer Applications, Detection, Diagnosis, Embolism, Thorax, ThrombosisSupplemental material is available for this article.© RSNA, 2023See also the commentary by Elicker in this issue.

Unreported incidental pulmonary embolism in patients with cancer: Radiologic natural history and risk of recurrent venous thromboembolism and death

PURPOSE

To assess the risk of recurrent venous thromboembolism (VTE) and death in patients with unreported cancer-associated incidental pulmonary embolism (iPE).

MATERIALS AND METHODS

Matched cohort study on cancer patients with a CT study including the chest between 2014-01-01 and 2019-06-30. Studies were reviewed for unreported iPE, and cases were matched with controls without iPE. Cases and controls were followed for one year, with recurrent VTE and death as outcome events.

RESULTS

Of the included 2960 patients, 171 patients had unreported and untreated iPE. While controls had a one-year VTE risk of 8.2 events per 100 person-years, cases with a single subsegmental iPE had a recurrent VTE risk of 20.9 events, and between 52.0 and 72.0 events per 100 person-years for multiple subsegmental iPE and more proximal iPE. In multivariable analysis, multiple subsegmental and more proximal iPE were significantly associated with the risk of recurrent VTE, while single subsegmental iPE was not associated with the risk of recurrent VTE (p = 0.13). In the subgroup of patients (n = 47) with cancer not in the highest Khorana VTE risk category, no metastases and up to three involved vessels, recurrent VTE occurred in two patients (4.7 cases per 100 person-years). There were no significant associations between iPE burden and risk of death.

CONCLUSION

In cancer patients with unreported iPE, iPE burden was associated with the risk of recurrent VTE. However, having a single subsegmental iPE was not associated with the risk of recurrent VTE. There were no significant associations between iPE burden and risk of death.

Spectral CT in Oncology

BACKGROUND

Spectral CT is gaining increasing clinical importance with multiple potential applications, including oncological imaging. Spectral CT-specific image data offers multiple advantages over conventional CT image data through various post-processing algorithms, which will be highlighted in the following review.

METHODOLOGY

The purpose of this review article is to provide an overview of potential useful oncologic applications of spectral CT and to highlight specific spectral CT pitfalls. The technical background, clinical advantages of primary and follow-up spectral CT exams in oncology, and the application of appropriate spectral tools will be highlighted.

RESULTS/CONCLUSIONS

Spectral CT imaging offers multiple advantages over conventional CT imaging, particularly in the field of oncology. The combination of virtual native and low monoenergetic images leads to improved detection and characterization of oncologic lesions. Iodine-map images may provide a potential imaging biomarker for assessing treatment response.

KEY POINTS

· The most important spectral CT reconstructions for oncology imaging are virtual unenhanced, iodine map, and virtual monochromatic reconstructions.. · The combination of virtual unenhanced and low monoenergetic reconstructions leads to better detection and characterization of the vascularization of solid tumors.. · Iodine maps can be a surrogate parameter for tumor perfusion and potentially used as a therapy monitoring parameter.. · For radiotherapy planning, the relative electron density and the effective atomic number of a tissue can be calculated..

CITATION FORMAT

· Sauerbeck J, Adam G, Meyer M. Onkologische Bildgebung mittels Spektral-CT. Fortschr Röntgenstr 2023; 195: 21 - 29.

Incidental pulmonary embolism in patients with cancer: prevalence, underdiagnosis and evaluation of an AI algorithm for automatic detection of pulmonary embolism

OBJECTIVES

To assess the prevalence of reported and unreported incidental pulmonary embolism (iPE) in patients with cancer, and to evaluate an artificial intelligence (AI) algorithm for automatic detection of iPE.

METHODS

Retrospective cohort study on patients with cancer with an elective CT study including the chest between 2018-07-01 and 2019-06-30. All study reports and images were reviewed to identify reported and unreported iPE and were processed by the AI algorithm.

RESULTS

One thousand sixty-nine patients (1892 studies) were included. Per study, iPE was present in 75 studies (4.0%), of which 16 (21.3%) were reported. Unreported iPE had a significantly lower number of involved vessels compared to reported iPE, with a median of 2 (interquartile range, IQR, 1-4) versus 5 (IQR 3-9.75), p < 0.001. There were no significant differences in age, cancer type, or attenuation of the main pulmonary artery. The AI algorithm correctly identified 68 of 75 iPE, with 3 false positives (sensitivity 90.7%, specificity 99.8%, PPV 95.6%, NPV 99.6%). False negatives occurred in cases with 1-3 involved vessels. Of the unreported iPE, 32/59 (54.2%) were proximal to the subsegmental arteries.

CONCLUSION

In patients with cancer, the prevalence of iPE was 4.0%, of which only 21% were reported. Greater than 50% of unreported iPE were proximal to the subsegmental arteries. The AI algorithm had a very high sensitivity and specificity with only three false positives, with the potential to increase the detection rate of iPE.

KEY POINTS

• In a retrospective single-center study on patients with cancer, unreported iPE were common, with the majority lying proximal to the subsegmental arteries. • The evaluated AI algorithm had a very high sensitivity and specificity, so has the potential to increase the detection rate of iPE.

Saddle Pulmonary Embolism in Patients with Cancer in the Era of Incidental Events: Clinical Findings and Outcomes in a Single Centre Cohort

Background  There is scarce information regarding the prevalence and clinical impact of saddle pulmonary embolism (PE) in patients with cancer. Objectives  This study aimed to assess the prevalence, clinical findings, and short-term outcomes of patients with cancer-related saddle PE including acute symptomatic and unsuspected events. Patients/Methods  Consecutive patients with cancer-related PE (March 1, 2006-October 31, 2014) were retrospectively reviewed by a chest radiologist to assess PE burden and signs of right ventricular (RV) overload. The clinical outcomes within 30 days were evaluated according to saddle versus nonsaddle PE. Results  Thirty-six (12%) out of 289 patients with newly diagnosed cancer-related PE presented with saddle PE. Saddle PE was found in 21 cases (58%) with acute symptomatic PE and the remaining 15 cases (42%) were found as unsuspected findings. Patients with saddle PE had more frequently experienced a previous thrombotic event (31 vs. 13%; p =0.008), and it occurred more frequently as an acute symptomatic event (58 vs. 39%; p =0.025) compared with those with nonsaddle PE. Signs of RV overload including RV/left ventricle ratio ≥1 (22 vs. 4%; p <0.001) and interventricular septum displacement (53 vs. 20%; p <0.001) were also more common in patients with saddle PE compared with nonsaddle PE. Overall, PE-related mortality, venous thromboembolism recurrence, and major bleeding within 30 days were found to be similar according to saddle versus nonsaddle PE. Conclusion  Saddle PE is not uncommon in patients with cancer-related PE including in those with unsuspected PE. Similar 30-day outcomes were found according to saddle versus nonsaddle PE in our cohort.

Pitfalls in the imaging of pulmonary embolism

Pulmonary embolism (PE) can present with a wide spectrum of clinical symptoms that can overlap considerably with other cardiovascular diseases. To avoid PE related morbidity and mortality, it is vital to identify this disease accurately and in a timely fashion. Several clinical criteria have been developed to standardize the diagnostic approach for patients with suspected PE. Computed tomographic pulmonary angiogram has significantly improved the detection of pulmonary embolism and is considered the imaging modality of choice to diagnose this disease. However, there are several potential pitfalls associated with this modality which can make diagnosis of PE challenging. In this review, we will discuss various pitfalls routinely encountered in the diagnostic work up of patients with suspected PE, approaches to mitigate these pitfalls and incidental pulmonary embolism.

Characteristics and outcomes of cancer patients who develop pulmonary embolism: A cross‑sectional study

Pulmonary embolism (PE), along with deep vein thrombosis, are collectively known as venous thromboembolism (VTE). Predisposing factors for PE include post-operative conditions, pregnancy, cancer and an advanced age; of note, a number of genetic mutations have been found to be associated with an increased risk of PE. The association between cancer and VTE is well-established, and cancer patients present a higher risk of a thrombotic event compared to the general population. In addition, PE is a significant cause of morbidity and mortality among cancer patients. The aim of the present study was to illustrate the clinical characteristics, laboratory findings, radiology features and outcomes of cancer patients who developed PE, collected from an anticancer hospital. For this purpose, adult cancer patients diagnosed with PE by imaging with computed tomography pulmonary angiography were enrolled. The following data were recorded: Demographics, comorbidities, type of cancer, time interval between cancer diagnosis and PE occurrence, the type of therapy received and the presence of metastases, clinical signs and symptoms, predisposing factors for PE development, laboratory data, radiological findings, electrocardiography findings, and the type of therapy received for PE and outcomes in a follow-up period of 6 months. In total, 60 cancer patients were enrolled. The majority of the cancer patients were males. The most common type of cancer observed was lung cancer. The majority of cases of PE occurred within the first year from the time of cancer diagnosis, while the majority of patients had already developed metastases. In addition, the majority of cancer patients had received chemotherapy over the past month, while they were not receiving anticoagulants and had central obstruction. A large proportion of patients had asymptomatic PE. The in-hospital mortality rate was 13.3% and no relapse or mortality were observed during the follow-up period. The present study demonstrates that elevated levels of lactic acid and an increased platelet count, as well as low serum levels of carcinoembryonic antigen, albumin and D-dimer, may be potential biomarkers for asymptomatic PE among cancer patients.

Incidence of pulmonary embolism and impact on mortality in patients with malignant melanoma

PURPOSE

Pulmonary embolism (PE) occurs frequently in patients with malignant melanoma (MM). The aim of this study is to determine the incidence of PE in patients with MM and to assess the clinical characteristics and mortality of MM patients with PE.

MATERIAL AND METHODS

Medical records from 381 MM patients who underwent contrast-enhanced computed tomography were evaluated. Imaging parameters including location of PE and measurements of right heart dysfunction and clinical parameters including D-Dimer levels, local and distant tumor stage and time of death were analyzed.

RESULTS

PE was found in 23/381 (6%) MM patients, whereby 17/23 (74%) were detected incidentally and only 6/23 (26%) were symptomatic. The presence of PE significantly correlated with elevated D-Dimers (p < 0.001), right ventricular dysfunction (p = 0.04), higher local tumor stage (≥T3) (p = 0.05), presence of visceral (p = 0.02) or cerebral metastases (p = 0.03) and increased mortality (p = 0.05). Further, patients with central PE showed an increased mortality compared to peripheral PE (p = 0.03), but no correlation was found between the localization of PE and the occurrence of clinical symptoms (p = 0.36).

CONCLUSION

PE in patients with MM often occurs without clinical symptoms and is indicative for advanced disease and a poorer prognosis.

Concurrence of Gastric Cancer and Incidental Pulmonary Embolism May Be a Prognostic Factor for Advanced Gastric Cancer Patients with Incidental Pulmonary Embolism

Objective

Cancer is well known as the most important risk factor for the emergence of pulmonary embolism (PE). The incidence of incidental PE (IPE) has increased with widely use of multi-detector-row computed tomography (CT) technology. Simultaneously, more new cancer patients diagnosed concomitantly with IPE are found. No study has examined the presentation and prognosis of incidental pulmonary embolism (IPE) in gastric cancer patients. The aim of this study was to analyse prognostic factors in patients with advanced gastric cancer complicated with IPE.

Patients and Methods

Ninety patients with histologically confirmed advanced gastric adenocarcinoma diagnosed with IPE were enrolled. Continuous variables were compared using Student’s t-test or the Mann–Whitney U-test if non-normally distributed. The Chi-squared test (or Fisher’s exact test where appropriate) was used to compare categorical variables. The Kaplan–Meier method and the Log rank test were used for survival analysis. Independent prognostic factors for survival were determined using a Cox proportional hazards model. A two-sided P-value < 0.05 was considered statistically significant.

Results

Nineteen patients were diagnosed with IPE concomitantly with gastric cancer. Concurrence of gastric cancer and IPE, lack of anticoagulation therapy, and location of IPE were associated with survival. After adjusting for age and sex, the concurrence of gastric cancer and IPE, lack of anticoagulation, and central IPE independently influenced the survival of advanced gastric cancer patients with IPE. Subgroup analysis of patients with peripheral pulmonary embolisms confirmed that anticoagulant therapy provided a survival benefit.

Conclusion

Concurrence of gastric cancer and IPE may be a prognostic factor for advanced gastric cancer patients with IPE.

The prevalence and clinical features of pulmonary embolism in patients with AE-COPD: A meta-analysis and systematic review

BACKGROUND

The prevalence of pulmonary embolism (PE) in the acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) is highly controversial. We conducted a systematic review and meta-analysis to summarize the epidemiology and characteristics of PE with AE-COPD for current studies.

METHODS

We searched the PubMed, EMBASE, Cochrane Library and Web of Science databases for studies published prior to October 21, 2020. Pooled proportions with 95% confidence intervals (95% CIs) were calculated using a random effects model. Odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals were used as effect measures for dichotomous and continuous variables, respectively.

RESULTS

A total of 17 studies involving 3170 patients were included. The prevalence of PE and deep vein thrombosis (DVT) in AE-COPD patients was 17.2% (95% CI: 13.4%-21.3%) and 7.1% (95% CI: 3.7%-11.4%%), respectively. Dyspnea (OR = 6.77, 95% CI: 1.97-23.22), pleuritic chest pain (OR = 3.25, 95% CI: 2.06-5.12), lower limb asymmetry or edema (OR = 2.46, 95% CI:1.51-4.00), higher heart rates (MD = 20.51, 95% CI: 4.95-36.08), longer hospital stays (MD = 3.66, 95% CI: 3.01-4.31) were associated with the PE in the AE-COPD patients. Levels of D-dimer (MD = 1.51, 95% CI: 0.80-2.23), WBC counts (MD = 1.42, 95% CI: 0.14-2.70) were significantly higher and levels of PaO2 was lower (MD = -17.20, 95% CI: -33.94- -0.45, P<0.05) in the AE-COPD with PE group. The AE-COPD with PE group had increased risk of fatal outcome than the AE-COPD group (OR = 2.23, 95% CI: 1.43-3.50).

CONCLUSIONS

The prevalence of PE during AE-COPD varies considerably among the studies. AE-COPD patients with PE experienced an increased risk of death, especially among the ICU patients. Understanding the potential risk factors for PE may help clinicians identify AE-COPD patients at increased risk of PE.

PROSPERO REGISTRATION NUMBER

CRD42021226568.

Clinical characteristics and outcomes of patients with isolated pulmonary embolism

The clinical relevance of concomitant deep vein thrombosis (DVT) in patients with pulmonary embolism remains controversial. The aim of the present study was to assess clinical characteristics of patients with isolated pulmonary embolism, thereby investigating isolated pulmonary embolism related clinical factors. Patients hospitalized for pulmonary embolism who underwent DVT workup within 3 days of pulmonary embolism diagnosis were retrospectively classified into two groups: patients with isolated pulmonary embolism and patients with DVT-associated pulmonary embolism (DVT-PE). The clinical, laboratorial and radiological parameters were compared between the two groups. Of 1012 patients, 322 (31.8%) presented with isolated pulmonary embolism, and 690 (68.2%) presented with DVT-PE. In a multivariate analysis, female sex was an independent factor for predicting isolated pulmonary embolism [odds ratio (OR) 1.69, 95% confidence interval (CI) 1.26-2.26, P < 0.001], whereas cancer (OR 0.64, 95% CI 0.43-0.96, P = 0.031), leg pain or swelling (OR 0.08, 95% CI 0.04-0.18, P < 0.001), and central pulmonary embolism (OR 0.44, 95% CI 0.32-0.59, P < 0.001) were negatively associated with isolated pulmonary embolism. There were no significant differences between the two groups with regard to risk stratification and short-term prognosis of pulmonary embolism, including adverse outcomes and pulmonary embolism related in-hospital mortality. Of pulmonary embolism patients who underwent imaging tests for DVT, approximately 32% presented with isolated pulmonary embolism. Isolated pulmonary embolism was positively associated with female sex, whereas it was negatively associated with cancer, leg pain or swelling, and central pulmonary embolism. The presence or absence of concomitant DVT did not influence the severity and short-term prognosis of pulmonary embolism.

Is COVID Evolution Due to Occurrence of Pulmonary Vascular Thrombosis?

In this hypothesis paper, we suggest that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may induce intravascular pulmonary thrombosis, which may result in the rapid worsening of clinical conditions and, eventually, exitus. Previously published papers have demonstrated that increased levels of D-dimer at hospital admission correlate with a more severe disease (0.5 mg/L) or occurrence of death (1 mg/L). The potential prothrombotic action of the SARS-CoV-2 is supported by the topographical involvement of the lung regions with a predilection for the lower lobe with peripheral involvement. If this hypothesis is demonstrated, this could suggest the benefit of using antithrombotic/coagulation regimens for SARS-CoV-2 and, at the same time, the urgency to identify drugs that could alter the inflammatory storm, thus protecting the vessel wall.

Clinical characteristics, management, and outcome of incidental pulmonary embolism in cancer patients

Incidental pulmonary embolisms (IPEs) are common in cancer patients. Examining the characteristics and outcomes of IPEs in cancer patients can help to ensure proper management, promoting better outcomes. To determine the clinical characteristics, management, and outcomes of IPEs for cancer patients, we conducted a 1:2 ratio case-control study and identified all consecutive patients with IPE who visited the emergency department at The University of Texas MD Anderson Cancer Center between 1 January 2006 and 1 January 2016. Each IPE case was matched with 2 controls using a propensity score obtained using logistic regression for IPE status with other factors affecting overall survival. A total of 904 confirmed cases were included in the analysis. IPE frequently occurred during the first year after cancer diagnosis (odds ratio [OR], 2.79; 95% confidence interval [95% CI], 2.37-3.29; P < .001). Patients receiving cytotoxic chemotherapy had a nearly threefold greater risk of developing IPE (OR, 2.87; 95% CI, 2.42-3.40; P < .001). In-hospital mortality was 1.9%. The 7- and 30-day mortality rates among the cases were 1.8% and 9.9%, respectively, which was significantly higher than in the control groups: 0.2% and 3.1%, respectively (P < .001). IPE was associated with reduced overall survival (hazard ratio [HR], 1.93; 95% CI, 1.74-2.14; P < .001). Concurrent incidental venous thromboembolism was identified in 189 of the patients (20.9%) and was also associated with reduced overall survival (HR, 1.65; 95% CI, 1.21-2.25; P = .001). Our results show that IPE events are associated with poor outcomes in cancer patients. Proper management plans similar to those of symptomatic pulmonary embolisms are essential.

Pulmonary Hypertension as a Complication of Pediatric Cancer

Pediatric cancer is a life threatening disease known to create multi-organ complications that further compromise medical management affecting patient morbidity and mortality. Pulmonary hypertension (PH) is becoming more recognized as a complication of cancer and its therapies but has not been well characterized in pediatrics. Cancer pathophysiology can be uniquely set up to promote pulmonary vascular injury and remodeling that is similar to PH patients without cancer. This highlights the need to evaluate for PH clinically and with routine testing such as echocardiography during the course of a patient's care even into adulthood. This review article will discuss the direct, indirect and therapy related aspects of cancer which can promote PH in these patients. This understanding is essential to target effective treatment options in a potentially fatal complication. Diagnostic and treatment algorithms are presented in relation to the most recent pediatric PH management guidelines.

The Diagnostic Value of FDG PET/CT and Thin-Slice High-Resolution Chest CT in Pulmonary Intravascular Metastasis

OBJECTIVE. Pulmonary intravascular metastasis is a special type of pulmonary metastasis of malignancies; however, few relevant studies have been performed. This study aimed to determine the characteristics of pulmonary intravascular metastasis and improve understanding of the disease by retrospective analysis of FDG PET/CT and thin-layer high-resolution CT (HRCT) imaging of the chest in patients with tumors. MATERIALS AND METHODS. We identified all patients who underwent FDG PET/CT at two hospitals between January 2016 and February 2019 and conducted a comparative analysis of HRCT and PET/CT images. In total, 84 patients (38 women and 46 men) ranging in age from 35 to 82 years old (mean age, 54.7 ± 14.5 [SD] years) participated in the study. Patient characteristics were summarized, and diagnosis was confirmed by chest CT or PET/CT follow-up. RESULTS. A total of 260 pulmonary intravascular metastases were found, which were classified as type I (no significant abnormality, n = 5), type II (abrupt and uneven thickening of the pulmonary vessel, n = 118), type III (simultaneous invasion of adjacent pulmonary vessel, n = 121), and type IV (large strip-shaped high-density mass, n = 16). The majority were located in peripheral pulmonary vessels (94.2% [245/260]). FDG up-take was increased in 252 lesions, and the mean SUV_max was 4.6 ± 2.5. CONCLUSION. The combination of PET/CT and chest HRCT is an effective approach for detecting pulmonary intravascular metastasis. The linear pattern of FDG uptake, abnormal pulmonary blood vessel morphology, and location (below the lung segment) are specific indicators for the diagnosis of pulmonary intravascular metastasis and should be recognized by clinicians and radiologists.

Prognostic Significance of Incidental Deep Vein Thrombosis in Patients with Cancer Presenting with Incidental Pulmonary Embolism

In symptomatic acute pulmonary embolism (PE), the presence of deep vein thrombosis (DVT) is a risk factor for 30- and 90-day mortality. In patients with cancer and incidental PE, the prognostic effect of concomitant incidental DVT is unknown. In this retrospective study, we examined the effect of incidental DVT on all-cause mortality in such patients. Adjusted Cox multivariate regression analysis was used for relevant covariates. From January 2010 to March 2018, we included 200 patients (mean age, 65.3 ± 12.4 years) who were followed up for 12.5 months (interquartile range 7.4-19.4 months). Of these patients, 62% had metastases, 31% had concomitant incidental DVT, and 40.1% (n = 81) died during follow-up. All-cause mortality did not increase in patients with DVT (hazard ratio [HR] 1.01, 95% confidence interval [CI] 0.43-2.75, p = 0.855). On multivariate analysis, weight (adjusted HR 0.96, 95% CI 0.92-0.99, p = 0.032), and metastasis (adjusted HR 10.26, 95% CI 2.35-44.9, p = 0.002) were predictors of all-cause mortality. In conclusion, low weight and presence of metastases were associated with all-cause mortality, while presence of concomitant DVT was unrelated to poorer survival.

Incidental pulmonary embolism in oncologic patients-a systematic review and meta-analysis

Purpose

Incidental pulmonary embolism (IPE) is a common finding on computed tomography (CT). IPE is frequent in oncologic patients undergoing staging CT. The aim of this analysis was to provide the pooled frequency of IPE and frequencies of IPE in different primary tumors.

Methods

MEDLINE, SCOPUS, and EMBASE databases were screened for studies investigating frequency of IPE in oncologic staging CT up to February 2020. Overall, 12 studies met the inclusion criteria and were included into the present study.

Results

The pooled analysis yielded a total of 28,626 patients. IPE was identified in 963 patients (3.36%, 95% CI = 3.15; 3.57). The highest frequency was found in prostate cancer (8.59%, 95%CI = 3.74; 13.44), followed by hepatobiliary carcinoma (6.07%, 95%CI = 3.09; 9.05) and pancreatic cancer (5.65%, 95%CI = 3.54; 7.76). The lowest frequencies were identified in tumors of male reproductive organs (0.79%, 95%CI = 0.21; 1.37) and hematological diseases (1.11% 95%CI = 0.74; 1.48).

Conclusion

The overall frequency of IPE in oncologic patients was 3.36%. There are considerable differences in regard to primary tumors with the highest frequency in prostate cancer and pancreatic and hepatobiliary carcinomas.

Clinical relevance of chronic respiratory disease in Korean patients with pulmonary thromboembolism

Background

Data regarding clinical and radiological features of patients with pulmonary thromboembolism (PTE) and concomitant chronic respiratory disease (CRD) are limited. Accordingly, the aim of the present study was to investigate clinico-radiological features of this patient population.

Methods

Patients with PTE were retrospectively classified into one of two groups: those with and without CRD. Clinical characteristics, blood biomarkers, and computed tomographic (CT) findings were compared between the groups.

Results

Of 1,207 PTE patients included, CRD was detected in 128 (11%). The most common CRD was chronic obstructive pulmonary disease [41 (32%)], followed by bronchial anthracofibrosis [32 (25%)]. In multivariate analysis, unprovoked PTE [odds ratio (OR) 1.99, 95% confidence interval (CI): 1.29-3.05, P=0.002], dyspnea (OR 1.54, 95% CI: 1.11-2.34, P=0.041), lower respiratory tract infection (LRTI) (OR 3.90, 95% CI: 2.13-7.14, P<0.001), Pulmonary Embolism Severity Index (PESI) class IV-V (OR 5.24, 95% CI: 3.43-8.00, P<0.001), in-situ pulmonary artery thrombosis (OR 10.62, 95% CI: 3.71-30.45, P<0.001), and pulmonary artery enlargement (OR 1.65, 95% CI: 3.71-30.45, P<0.001) were found to be independent clinical factors related to CRD in patients with PTE. CRD was an independent predictor of PTE-related in-hospital mortality (OR 3.96, 95% CI: 1.32-11.88, P=0.014).

Conclusions

Patients with PTE and concomitant CRD were characterized by higher incidences of dyspnea, LRTI, PESI class IV-V, and in-situ pulmonary artery thrombosis, compared with non-CRD patients. In these patients, CRD was a predictor of PTE-related in-hospital mortality.

Computer-assisted detection of acute pulmonary embolism at CT pulmonary angiography in children and young adults: a diagnostic performance analysis

Background

To diagnose pulmonary embolism (PE) in children and adults since evaluating tiny pulmonary vasculature beyond segmental level is a challenging and demanding task with thousands of images.

Purpose

To evaluate the effect of computer-assisted detection (CAD) on acute PE on CTPA in children and young adults by readers with varying experience levels.

Material and Methods

Six radiologists were retrospectively divided into three groups according to experience levels and assessed the CTPA studies on a per-emboli basis. All readers identified independently the PE presence, and ranked diagnostic confidence on a 5-point scale with and without CAD. Reading time, sensitivities, specificities, accuracies, positive predictive values (PPVs), and negative predictive values (NPVs) were calculated for each reading.

Results

The sensitivities and NPVs differed significantly in most readers ( P = 0.004, 0.001, 0.010, 0.010, and 0.012 for sensitivities and P = 0.011, 0.003, 0.016, 0.017, and 0.019 for NPVs) except for reader 6 ( P = 0.148 and 0.165, respectively), and the accuracies of all readers differed significantly (all P < 0.05) in peripheral PE (beyond segmental level) detection readings with CAD versus without CAD between two reading methods. The overall time using CAD was longer than those without CAD (76.6 ± 54.4 s vs. 49.4 ± 17.7 s, P = 0.000) for all readers. Significant differences were found for confidence scores in inter-group measurements with CAD ( P = 0.045) and without CAD ( P < 0.001).

Conclusion

At the expense of longer reading time, the use of the CAD algorithms improves sensitivities, NPVs, and the accuracies of readers in peripheral PE detection, especially for readers with a poor level of interpretation experience.

Detection efficiency of 18F-flourodeoxyglucose positron emission tomography/computed tomography for primary tumors in patients with carcinoma of unknown primary

Carcinoma of unknown primary (CUP) is defined as biopsy proven tumor metastases that remains unidentified after a thorough diagnostic evaluation. The purpose of this study was to find the detection efficiency of ¹⁸F-flourodeoxyglucose positron emission tomography/computed tomography (¹⁸FDG PET/CT) in patients with CUP. This prospective study was conducted at PET/CT Section of Department of Radiology, Aga Khan University Hospital Karachi, Pakistan from August 2017 to January 2018. Patients with a history of CUP referred for ¹⁸FDG PET/CT scan for detection of primary sites during the study were recruited. ¹⁸FDG PET/CT scan was acquired using standardized protocol, and patients with suspected primary sites underwent biopsies. Scan findings and biopsy results were analyzed to find the detection rate, sensitivity, area under curve (AUC), and positive predictive value (PPV). As no biopsy was performed in negative scan, true negative, and specificity could not be calculated. During the study, 46 consecutive patients with CUP were included. Mean age of cohort was 58 ± 17 years (63% male and 37% female) having a mean body mass index of 24.70 ± 4.97 kg/m². Thirty-four patients (34/46) found to have a hypermetabolic focus suggestive of the primary tumor with known metastatic sites and subjected to biopsy which turned out to be positive in 26/34 patients (true positive). The primary tumor was detected in gastrointestinal and hepatobiliary in 8 (17%), head and neck in 6 (13%), genitourinary 4 (09%), lung 3 (06%), and miscellaneous sites in 5 (11%) patients. Detection rate, sensitivity and PPV of ¹⁸FDG PET/CT were 57%, 68%, and 76%, respectively. Remaining 12/46 patients with negative ¹⁸FDG PET/CT for primary focus did not have biopsy. Receiver operating character curve revealed fair diagnostic strength of ¹⁸FDG PET/CT for detecting unknown primary (AUC 0.667; P = 0.054; standard error = 0.083; confidence interval: 0.504–0.830). We conclude that ¹⁸FDG PET/CT is an effective tool for detecting primary tumor in patients with CUP and its upfront use could preclude the use of many futile diagnostic procedures. Furthermore, higher resolution scanners and acquiring delayed images in patients with negative study could reduce false-negative results in patients with CUP.

Low relative muscle volume: Correlation with prevalence of venous thromboembolism following total knee arthroplasty

Background

There have been many efforts to find modifiable risk factors for venous thromboembolism (VTE) in the perioperative period of total knee arthroplasty (TKA), while no study has investigated the relationship between the muscle mass and deep vein thrombosis (DVT) or pulmonary embolism frequency following TKA. This study aimed to evaluate the relationship between muscle volume and the prevalence of symptomatic and radiologically confirmed venous thromboembolism (VTE) after total knee arthroplasty (TKA).

Methods

A total of 261 consecutive patients who underwent primary TKA between 2013 and 2015 were enrolled. Computed tomographic venography with pulmonary angiography (CTVPA) was performed between the 5th and 7th postoperative days to assess the presence of VTE. Four parameters of muscle volume at three levels were evaluated on CTVPA: (i) the cross-sectional area of all skeletal muscles (skeletal muscle index) and total psoas area at the level of the third lumbar vertebrae; (ii) the vastus lateralis muscle at the thigh level; and (iii) the posterior crural muscle at the lower leg level. The relationship between the muscle volume at each level and the prevalence of VTE after TKA was evaluated with multivariate adjusted logistic regression models.

Results

The CTVPA scan showed no proximal DVT, and all thrombi were located in muscular, peroneal, and posterior tibial veins. In unilateral TKA, patients with lower muscle volume of the vastus lateralis at the thigh level in the nonoperated limb had significantly higher prevalence of distal DVT in the operated limb (adjusted OR: 2.97 at subclinical DVT revealed by CTVPA and adjusted OR: 2.68 at symptomatic DVT). This finding was also discovered in patients who underwent simultaneous bilateral TKA (adjusted OR: 1.73–2.97 at subclinical DVT and adjusted OR:1.76–1.86 at symptomatic DVT).

Conclusions

The relative muscle volume of the vastus lateralis at the thigh level was negatively associated with the prevalence of symptomatic and radiologically confirmed DVT, suggesting that low thigh muscle mass is an independent risk factor for VTE in the postoperative period of TKA.

The Rate of Venous Thromboembolism Before and After Spine Surgery as Determined with Indirect Multidetector CT

BACKGROUND

This prospective cohort study investigated the rate of venous thromboembolism (VTE) before and after spine surgery as determined with use of indirect multidetector computed tomography (MDCT).

METHODS

We performed a prospective study of 105 patients (36 women and 69 men ranging in age from 38 to 88 years) undergoing spine surgery at 2 institutions. Indirect MDCT was performed before and 3 days after surgery. Patients with a history of dialysis or drug allergy to contrast medium were excluded.

RESULTS

No patient had symptomatic VTE preoperatively or postoperatively. The preoperative and postoperative rates of asymptomatic VTE were 4.8% and 13.0%, respectively; the rates of asymptomatic pulmonary embolism were 2.9% and 8.0%, respectively; and the rates of asymptomatic deep venous thrombosis were 3.8% and 6.0%, respectively. Age, sex, height, weight, body mass index, operative time, volume of intraoperative blood loss, and specific comorbidities (diabetes, hypertension, cardiac disease, previous VTE, and previous anticoagulation treatment) were not found to be risk factors.

CONCLUSIONS

Our findings demonstrated a low rate of preoperative VTE but a high rate of postoperative VTE in association with spine surgery. Surgeons need to be aware of the risk of VTE in patients undergoing spine surgery. MDCT is an effective and convenient technology for the early detection of VTE in such patients.

LEVEL OF EVIDENCE

Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Incidental findings during follow-up scans in oncological patients

Background and aim

To assess the prevalence of incidental findings during follow-up scans of patients with oncologic pathology.

Methods

499 follow-up scans from different patients with cancer pathology were retrospectively analyzed. Findings which were not suspected by the clinician or known from previous scans were considered as incidental lesions. We excluded lesions that were already suspected by the clinician or were already recorded in the patient’s history before the initial computed tomography (CT) scan. The CT scans were performed on two different machines (“Siemens Somatom Sensation, 64 slices, Erlangen, Germany” and “Siemens Somatom Emotion, 16 slices, Erlangen, Germany”).

Most of the patients had a native scan followed by a thoraco-abdominal-pelvic image acquisition after the injection of intravenous contrast media.

Results

28% of the patients had unsuspected incidental findings. The prevalence of incidental findings was similar: 56.6% of them were found in men and 43.4% in female patients. In 6 cases (1.2%) the presence of unsuspected pulmonary embolism was discovered. From these cases, 5 (83.3%) had metastatic disease at the moment of the follow-up CT scan and 1 (16.6%) had metastasis-free disease. In 17 patients out of 499 (3.4%) we incidentally made an important discovery which either changed the cancer therapy or required immediate treatment.

Conclusion

Incidental findings are not rare in oncological patients and the radiologist has to be aware of their presence in order not to overlook them and to correctly diagnose them.

Incidental pulmonary emboli in stage IV melanoma patients: Prevalence in CT staging examinations and improved detection with vessel reconstructions based on dual energy CT

OBJECTIVES

Malignancy is the strongest predictor for venous thromboembolism. Dual energy CT (DECT) can support assessment of pulmonary emboli (PE) by providing vessel reconstructions (DECT-VR) and highlighting thrombi. Purpose was to determine prevalence and risk factors of PE in staging examinations of stage IV-melanoma patients and to evaluate the potential of DECT-VR to improve PE diagnosis.

MATERIAL AND METHODS

This retrospective study was approved by IRB. Contrast-enhanced, conventional grey scale CT (cCT) and DECT-VR of 200 stage IV-melanoma patients were reviewed by three radiologists in consensus. Overall prevalence was determined. One-sided Wilcoxon-test was performed to compare the number of detected emboli between cCT and cCT with supplementary DECT-VR. Frequencies of risk factors were compared with χ2 test.

RESULTS

On cCT, 9 PE were detected (6 patients, correlating to 3% of the study population with 0.05 emboli per patient). With the supplementary DECT-VR, number of diagnosed emboli increased from 9 to 17 (p < 0.05) (in total 9 patients, correlating to 0.09 emboli per patient). Emboli on DECT-VR were mainly subsegmentally (7 of 8). There was no significant difference in the frequency of risk factors.

CONCLUSIONS

The prevalence of pulmonary emboli in our cohort of 200 stage IV melanoma patients was 5%. DECT-VR improved significantly diagnosis of PE, especially when located subsegmentally.

Pulmonary thromboembolism: new diagnostic imaging techniques

The accurate diagnosis of pulmonary thromboembolism is essential to reducing the morbidity and mortality associated with the disease. The diagnosis of pulmonary thromboembolism is challenging because of the nonspecific nature of the clinical profile and the risk factors. Imaging methods provide the definitive diagnosis. Currently, the imaging method most commonly used in the evaluation of pulmonary thromboembolism is computed tomography. The recent development of dual-energy computed tomography has provided a promising tool for the evaluation of pulmonary perfusion through iodine mapping. In this article, we will review the importance of diagnosing pulmonary thromboembolism, as well as the imaging methods employed, primarily dual-energy computed tomography.

Managing Incidental Findings on Thoracic CT: Mediastinal and Cardiovascular Findings. A White Paper of the ACR Incidental Findings Committee

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected mediastinal and cardiovascular findings found on CT. The Chest Subcommittee was composed of thoracic radiologists who developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address the most commonly encountered mediastinal and cardiovascular incidental findings and are not intended to be a comprehensive review of all incidental findings associated with these compartments. Our goal is to improve the quality of care by providing guidance on how to manage incidentally detected thoracic findings.

High energy injury is a risk factor for preoperative venous thromboembolism in the patients with hip fractures: A prospective observational study

BACKGROUND

The purpose of this study was to identify the incidence of preoperative venous thromboembolism (VTE), and determine if high energy hip fracture affects preoperative VTE occurrence.

METHODS

Three-hundred nine patients (244 low and 61 high energy injuries) treated between March 2015 and March 2017 were included in this study. Indirect multidetector computed tomographic venography for the detection of preoperative VTE was performed at admission. The incidence of preoperative VTE was compared between high and low energy injury hip fractures. Logistic regression analysis was used to identify independent risk factors for preoperative VTE.

RESULTS

The overall incidence of preoperative VTE was 18.4% (56 of 305 patients). Preoperative VTE was identified in 17 (27.9%) and 39 (16.0%) patients in the high and low energy injury groups, respectively (p = 0.034). Multivariate logistic regression analysis showed that high energy injury, history of VTE, and myeloproliferative disease were significant predictive factors of preoperative VTE (OR = 2.451; 95% CI = 1.227-4.896, OR = 11.174; 95% CI = 3.500-35.673, OR = 6.936; 95% CI = 1.641-29.321, respectively) CONCLUSION: Because high energy hip fracture is significantly associated with preoperative VTE occurrence, preoperative evaluation and proper thromboprophylaxis should be performed for patients with a high-energy hip fracture.

Asymptomatic Pulmonary Embolism in Lung Cancer: Prevalence and Analysis of Clinical and Radiological Characteristics in 141 Outpatients

Aims and background

The incidence of asymptomatic pulmonary embolism in cancer patients is unknown and strictly related to the imaging used for tumor assessment. Recent findings suggest a similar clinical outcome of asymptomatic pulmonary embolism events compared to symptomatic events with a significant impact on survival. The aim of the present study was to determine the prevalence of asymptomatic pulmonary embolism in a population of lung cancer outpatients and to investigate its clinical features.

Methods

Outpatients with a diagnosis of lung carcinoma undergoing chemotherapy were selected from October 2006 to June 2009. Disease and patient characteristics, risk factors and treatment modalities were collected. All the computed tomography images performed for each patient during the study period were retrospectively reviewed to identify pulmonary embolism.

Results

A total of 141 consecutive patients were included and 657 computed tomography scans were completely reviewed (from two to six consecutive scans for each patient). Asymptomatic pulmonary embolism in the study population had a prevalence of 14.9% (21 patients). Most of the events occurred in patients with adenocarcinoma, advanced stage and poor performance status, during the early phases of first-line chemotherapy or at the same time of the cancer diagnosis. Compared with the symptomatic pulmonary embolism events (5 patients), asymptomatic events occurred earlier (time from cancer diagnosis to pulmonary embolism of 3.5 [95% CI, 2.0–4.9] versus 12.1 months [95% CI, 6.3–17.9; P = 0.02]) and had a better prognosis (survival from PE of 7.5 [95% CI, 3.4–11.6] versus 1.9 months [95% CI, 0–3.9; P = 0.04]).

Conclusions

Our findings indicate an underestimation of embolic events among lung cancer outpatients due to their frequent asymptomatic natur. Such a high prevalence suggests the importance to pay more attention to pulmonary embolism prevention in this population.

Pulmonary embolism concurrent with lung cancer and central emboli predict mortality in patients with lung cancer and pulmonary embolism

Background

Patients with lung cancer commonly experience pulmonary embolism (PE). The aim of the present study was to examine the clinical features of patients with lung cancer and PE and to investigate prognostic factors in these patients.

Methods

This retrospective study divided patients with lung cancer and PE into a group of patients with PE diagnosed concomitantly with lung cancer (concurrent group) and a group with PE detected after lung cancer (sequential group), compared the clinical characteristics of patients in the two groups, and investigated prognostic factors in these patients.

Results

The study population consisted of the concurrent group [27 patients (10.1%)] and the sequential group [240 patients (89.9%)]. The concurrent group exhibited higher percentages of stage I cancer at the diagnosis of PE [6 (22.2%) vs. 8 (3.3%), P<0.001] and right ventricular (RV) dilation on computed tomography (CT) [14 (51.9%) vs. 41 (17.1%), P<0.001], as well as lower rate of small cell carcinoma [1 (3.7%) vs. 49 (20.4%), P=0.036] than the sequential group. PE concurrent with lung cancer [hazard ratio (HR) =2.64, 95% confidence interval (CI): 1.57-4.43, P<0.001] and central PE (HR =1.46, 95% CI: 1.02-2.10, P=0.04) were independent predictors of mortality in patients with lung cancer and PE.

Conclusions

PE concurrent with lung cancer is characterized by more severe PE and infrequent small cell carcinoma. PE concurrent with lung cancer and central emboli may be independent prognostic factors in patients with lung cancer and PE.

Incidental venous thromboembolism: is anticoagulation indicated?

Patients with cancer have a high risk of venous thromboembolism (VTE) and about one-half of these events are incidentally detected. The prognosis of incidental VTE appears to be similar to symptomatic events, with comparably high rates of recurrent VTE in this patient population. In the absence of major contraindications, anticoagulant treatment with low-molecular-weight heparin for 3 to 6 months is generally recommended for incidental proximal deep vein thrombosis as well as for incidental pulmonary embolism that involves multiple subsegmental or more proximal pulmonary arteries. The decision of whether to extend treatment beyond 3 to 6 months should be evaluated on a case-by-case basis after periodic reassessment of the risks factors for bleeding and recurrent VTE while also taking into account patient preferences. The clinical relevance of a single incidental subsegmental pulmonary embolism without concomitant deep vein thrombosis is uncertain and either a watchful approach or a shorter course of anticoagulation to minimize the bleeding risk may also be considered. Preliminary evidence suggests that anticoagulation treatment may be beneficial for cancer patients with incidental distal deep vein thrombosis or incidental splanchnic vein thrombosis.

Management of incidental pulmonary embolism

Incidental pulmonary embolism (PE) is a frequent finding on routine computed tomography (CT) scans of the chest, occurring in 1.1% of coronary CT scans and 3.6% of oncological CT scans. Despite this high frequency, optimal management of incidental PE has not been addressed in clinical trials and remains the subject of debate. Although these CT scans have not been performed with a dedicated PE protocol and have suboptimal contrast enhancement, diagnosis of incidental PE has been shown to be accurate up to the segmental and subsegmental arteries. The embolic load in incidental PE is lower than that in symptomatic PE. Even so, observational studies suggest that the natural course of incidental PE is similar to that of symptomatic PE with regard to the risk of recurrent venous thrombotic disease and mortality. Interestingly, the increased use of more advanced CT technology has coincided with an increase in the rate of incidental subsegmental PE, as is the case for symptomatic subsegmental PE. Although clinical trials are lacking, and observational data are limited to cancer-associated incidental PE, the consensus is that the management of incidental PE is identical to that of symptomatic PE, including the choice of optimal drug class, outpatient treatment and total duration of treatment.

Key points to optimizing management and research on cancer-associated thrombosis

Despite the fact that thromboembolism is relatively common in oncology patients and that the interrelationship between thrombotic risk and specific mechanisms of tumorigenesis has long been known, many cardinal elements of prevention and treatment remain unresolved. Among the existing knowledge gaps, the need to validate the Ay scale and compare it to the Khorana index, develop, and standardize the use of predictive biomarkers for thrombotic risk, conduct clinical trials in thromboprophylaxis adapted to thrombotic risk, evaluate the efficacy and safety of direct anticoagulants, select patients who can benefit from anticoagulants for antitumor treatment, validate the EPIPHANY study decision tree to choose patients with low-risk pulmonary embolism, and accumulate more practical experience in special situations (rethrombosis, prolonged therapy beyond 6 months, etc.) are especially remarkable. These gray areas surrounding cancer-related thromboembolism explain why it continues to be a relatively common cause of serious events, at times interfering significantly with the development of new tumor-fighting strategies.

Risk factors and prognosis of pulmonary embolism in patients with lung cancer

Malignant tumors are often complicated with venous thrombosis and pulmonary embolism (PE), particularly in lung cancer. However, owing to the limited data regarding the clinical course about PE in lung cancer patients, the aim of this study is to analyze the risk factors and prognosis of patients with PE and lung cancer. We performed a retrospective case-control study, the clinical data of 90 patients in the First Affiliated Hospital of People's Liberation Army General Hospital between Jan 2010 and Jan 2015 were analyzed, including 30 lung cancer patients with PE (PE group), 60 lung cancer patients without PE (non-PE group), treated during the same period. Logistic regression analysis was applied to explore risk factors of PE. Patient survival was also compared with matched controls via a log-rank test. The multivariate analysis revealed that adenocarcinoma, stage III to IV, high D-dimer, and low PaO2 were independent risk factors. The survival time in patients with PE was remarkably lower than that in patients without PE (P < .0005). Adenocarcinoma, stage III to IV, high D-dimer and low PaO2 are important risk factors for lung cancer patients with PE. PE suggested a poor prognosis in lung cancer patients.

[Clinically relevant incidental cardiovascular findings in CT examinations]

BACKGROUND AND METHOD

Incidental cardiovascular findings are a frequent phenomenon in computed tomography (CT) examinations. As the result of a dedicated PubMed search this article gives a systemic overview of the current literature on the most important incidental cardiovascular findings, their prevalence and clinical relevance.

RESULTS

The majority of incidental cardiovascular findings are of only low clinical relevance; however, highly relevant incidental findings, such as aortic aneurysms, thromboses and thromboembolic events can also occasionally be found, especially in oncology patients.

CONCLUSION

The scans from every CT examination should also be investigated for incidental findings as they can be of decisive importance for the further clinical management of patients, depending on their clinical relevance.

Improved detection of melanoma metastases by iodine maps from dual energy CT

OBJECTIVE

Metastatic disease in melanoma has an unpredictable nature with deposits in rare locations such as musculature. Dual energy CT (DECT) provides high contrast-visualization of enhancement by using spectral properties of iodine. Purpose of this study was to evaluate whether iodine maps from DECT improve lesion detection in staging examinations of melanoma patients.

METHODS

This retrospective study was approved by IRB and written informed consent was obtained from all patients. 75 contrast-enhanced DECT scans (thorax and abdomen) from 75 melanoma patients (n=69 stage IV; n=6 stage III) were analysed. For each patient, conventional CT and iodine maps were reviewed independently by two radiologists. The number of lesions detected by reviewing the iodine maps following conventional CT was recorded. Unweighted Cohens Kappa coefficient (κ) was used for concordance analysis, Wilcoxon test for comparing lesion detection rates.

RESULTS

In 26 patients, at least one reader found additional lesions on iodine maps (inter-reader agreement 89%, κ=0.74 (0.742-0.747)). Compared to grey-scale images, mean detection rate for metastases improved from 86% (range 82-90) to 94% (90-99%) (p≤0.01), for muscle metastases from 8% (8-8%) to 99% (98-100%) (p≤0.06). Findings included 2 pulmonary emboli.

CONCLUSION

Iodine maps from DECT improve detection of metastases, especially muscle metastases, and relevant findings in staging examinations of melanoma patients.

Prospective cohort study of cancer patients diagnosed with incidental venous thromboembolism on routine computed tomography scans

PURPOSE

Venous thromboembolism (VTE) is a major complication of cancer with recent increasing reports of incidental VTE. The objectives are to estimate the prevalence of incidental VTE in cancer patients on staging CT scans, identify common symptoms, and determine VTE recurrence in a prospective study.

PATIENTS AND METHODS

One thousand ninety patients were studied. Adult cancer patients scheduled for outpatient staging CT scans were eligible. VTE cases were followed for 6 months. Fisher's exact test for group comparisons of categorical variables and generalized linear modeling to estimate the prevalence of incidental VTE was used.

RESULTS

The mean age was 58 years (range 18-87 years); 50% were male. The prevalence of incidental VTE was 1.8% (CI 1.15-2.87%). Significant symptoms in patients with VTE included fatigue (p = 0.004), stress (p = 0.0195), depression (p = 0.019), poorer quality of life (p = 0.0194), and poorer physical well-being (p = 0.0007). All the patients with VTE had at least one comorbidity (p = 0.03). No patient had recurrence within 6 months.

CONCLUSION

The prevalence of incidental VTE on staging CT scans is lower than previously reported. Symptoms were associated with VTE; however, further work is needed to understand whether these are clinically relevant. No VTE recurrences were noted following 6 months.

Preoperative Prevalence of and Risk Factors for Venous Thromboembolism in Patients with a Hip Fracture: An Indirect Multidetector CT Venography Study

BACKGROUND

This retrospective cohort study investigated the prevalence of and risk factors for preoperative venous thromboembolism (VTE) in patients with a hip fracture and a delay of >24 hours from injury to surgery.

METHODS

This observational study included 208 patients with a hip fracture surgically treated at 1 university hospital between December 2010 and August 2014. Patients underwent indirect multidetector computed tomographic (MDCT) venography for preoperative VTE detection after admission. Overall VTE risk and median time from injury to CT scan were calculated. Age, sex, fracture type, time from injury to CT scan, body mass index, preinjury mobility score, previous anticoagulation treatment, previous hospitalization for VTE, varicose veins, and medical comorbidities were considered potential risk factors.

RESULTS

The prevalence of preoperative VTE was 11.1% (23 of 208 patients), including 12 patients with deep vein thrombosis alone, 7 patients with pulmonary embolism alone, and 4 patients with both. The mean time from injury to CT scan was 4.9 days. The delay from the time of injury to CT scan averaged 7.6 days for patients who developed preoperative VTE, compared with 4.2 days for patients who had not developed VTE. In the adjusted models, female sex, subtrochanteric fracture, pulmonary disease, cancer, previous hospitalization for VTE, and varicose veins were risk factors for VTE. The final multivariate logistic regression analysis demonstrated that female sex (odds ratio [OR] = 5.86; 95% confidence interval [CI] = 1.21 to 28.21), subtrochanteric fracture (OR = 22.17; 95% CI = 4.02 to 122.06), pulmonary disease (OR = 21.10; 95% CI = 5.35 to 83.21), and previous hospitalization for VTE (OR = 16.36; 95% CI = 3.41 to 78.43) increased the risk of VTE.

CONCLUSIONS

Our findings show a high prevalence of preoperative VTE in patients with a hip fracture. Therefore, preoperative investigation for VTE should be routinely considered for patients in whom surgery is delayed for >24 hours. At this time, indirect MDCT venography seems to be effective and useful.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Prognostic value of computed tomography pulmonary angiography indices in patients with cancer-related pulmonary embolism: Data from a multicenter cohort study

OBJECTIVE

To analyze the prognostic value of pulmonary artery obstruction versus right-ventricle (RV) dysfunction radiologic indices in cancer-related pulmonary embolism (PE).

METHODS

We enrolled 303 consecutive patients with paraneoplastic PE, evaluated by computed tomography pulmonary angiography (CTPA) between 2013 and 2014. The primary outcome measure was serious complications at 15days. Multivariate analyses were conducted by using binary logistic and robust regressions. Radiological features such as the Qanadli index (QI) and RV dysfunction signs were analyzed with Spearman's partial rank correlations.

RESULTS

RV diameter was the only radiological variable associated with an adverse outcome. Subjects with enlarged RV (diameter>45mm) had more 15-day complications (58% versus 40%, p=0.001). The QI correlated with the RV diameter (r=0.28, p<0.001), left ventricle diameter (r=-0.19, p<0.001), right ventricular-to-left ventricular diameter ratio (r=0.39, p<0.001), pulmonary artery diameter (r=0.22, p<0.001), and pulmonary artery/ascending aorta ratio (r=0.27, p<0.001). A QI≥50% was only associated with 15-day complications in subjects with enlarged RV, inverted intraventricular septum, or chronic cardiopulmonary diseases. The central or peripheral PE location did not affect the correlations among radiological variables and was not associated with clinical outcomes.

CONCLUSIONS

Right ventricular dysfunction signs in CTPA are more useful than QI in predicting cancer-related PE outcome.