Multimodality Imaging of Abdominopelvic Tumors with Venous Invasion

Management Strategies and Outcomes of Tumor Thrombus in Extremity Osteosarcoma

Osteosarcoma, accounting for 2.4% of all childhood malignancies and about 20% of primary bone cancers, primarily affects young adults, with 60% of cases occurring before age 25. Tumor thrombus (TT) formation, a type of cancer-associated thrombosis, is a rare but critical complication in osteosarcoma, leading to increased morbidity and mortality. TT is characterized by the direct extension of the tumor into adjacent vessels, displaying similar imaging characteristics and contrast enhancement as the primary tumor. Our study is a case series of five cases of extremity osteosarcoma where the presence of tumor thrombus has been diagnosed, highlighting diagnostic challenges and management strategies. Preoperative identification of TT remains difficult and is often diagnosed postoperatively or at autopsy. Advanced imaging techniques such as Computed Tomography, Magnetic Resonance Imaging, and Positron Emission Tomography can aid in the detection of TT, although they are not definitive. Surgical resection combined with thrombectomy is recommended, improving prognosis. Anticoagulation therapy aims to prevent bland thrombus formation rather than resolving TT, as the latter increases the risk of embolization. This study underscores the need for heightened suspicion and comprehensive preoperative imaging to improve outcomes in osteosarcoma patients with TT, advocating for multidisciplinary management including vascular surgeons during limb salvage procedures. Further research is essential to optimize anticoagulation protocols and validate these findings in larger cohorts.

Imaging of the Inferior Mesenteric Vasculature

The inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) supply and drain blood from the distal colon and rectum, respectively. Routinely imaged at cross-sectional imaging of the abdomen and pelvis, these vessels play a vital role in gastrointestinal tract health but may be neglected due to their diminutive caliber relative to other mesenteric vessels and potential lack of inclusion in routine search patterns. The authors describe and illustrate normal and abnormal appearances of the IMA and IMV and findings that are diagnostic of primary vascular abnormalities or can offer diagnostic clues. After the embryologic features, normal anatomy, and anatomic variants of the IMA and IMV are reviewed, various manifestations of IMA and IMV abnormalities, such as aneurysm and pseudoaneurysm, stenosis, occlusion, dissection, hemorrhage, arteriovenous malformations and fistulas, tumoral invasion, vasculitis, and perivascular lymphatic dilatation, are explored with use of case examples. The role of the IMA and IMV as collateral vasculature, including the clinical scenarios of superior mesenteric arterial occlusion, aortic endoleak, and portosystemic venous shunt, are discussed. Finally, diagnostic clues that the inferior mesenteric vessels and adjacent soft tissues can provide, including mesenteric venous gas, compression or displacement from bowel volvulus or internal hernias, lymphadenopathy, and venous flow artifacts, are highlighted. The authors provide a comprehensive reference for radiologists who evaluate the IMA and IMV on cross-sectional images and shine a spotlight on these neglected but important vessels. ©RSNA, 2024 Supplemental material is available for this article.

Cinematic Rendering of Pancreatic Neuroendocrine Tumours: Opportunities for Clinical Implementation: Part 1: Tumour Detection and Characterization

Pancreatic neuroendocrine tumours (PNETs) are a rare subset of pancreatic tumours that have historically comprised up to 3% of all clinically detected pancreatic tumours. In recent decades, however, advancements in imaging have led to an increased incidental detection rate of PNETs and imaging has played an increasingly central role in the initial diagnostics and surgical planning of these tumours. Cinematic rendering (CR) is a 3D post-processing technique that generates highly photorealistic images through more realistically modelling the path of photons through the imaged volume. This allows for more comprehensive visualization, description, and interpretation of anatomical structures. In this 2-part review article, we present the first description of the various CR appearances of PNETs in the reported literature while providing commentary on the unique clinical opportunities afforded by the adjunctive utilization of CR in the workup of these rare tumours. The first of these 2 instalments highlights the utility of CR in optimizing PNET detection and characterization.

Utility of metabolic ratios in the diagnosis of tumor Thrombus on F-18 FDG PET/CT

BACKGROUND

This study aims to predict quantitative parameter in form of metabolic ratios to diagnose tumor thrombus on F-18 FDG PET/CT.

METHODS

This is a retrospective study from Nuclear Medicine department at All India Institute of Medical Sciences, Jodhpur, India. Patients with malignancies who underwent F-18 FDG PET/CT in our department or images sent for review from February 2020 till September 2022 were screened for tumor thrombus that comprised study group. Control group had patients with malignancy and no imaging evidence of tumor thrombus. Metabolic activities (SUVmax) of tumor thrombus, liver and descending aorta in study group, and that of IVC, liver and descending aorta in control group were recorded. Metabolic ratios of tumor thrombus to liver (SUR L) and to aorta (SUR A) in study group, and IVC to liver (SUR* L) and to aorta (SUR*A) in control group were compared using receiver operator curves.

RESULTS

Of 2277 studies screened, 12 had tumor thrombus. The most common primary malignant site and vessel involved were lung and IVC respectively. The median (IQR) SUR L, SUR A, SUR* L and SUR* A were 2.5 (3.25), 2.6  (6), 0.67 (0.18) and 1 (0.17) respectively. Area under ROC for SUR L and SUR A were 0.983 [95% CI: 0.955-1.0] and 0.958 [95% CI: 0.90-1.0] respectively. The ideal cut-off for SUR L was 0.953 (sensitivity 92.3%, specificity 98.0%) and for SUR A was 1.42 (sensitivity 84.6%, specificity 98.0%).

CONCLUSION

Metabolic ratios of tumor thrombus to liver (SUR L) and aorta (SUR A) have good diagnostic performance and can be useful in studies with non-iodinated contrast CT.

The Portal Vein: A Comprehensive Review

Radiologists are familiar with the appearances of a normal portal vein; variations in its anatomy are commonplace and require careful consideration due to the implications for surgery. These alterations in portal vein anatomy have characteristic appearances that are clearly depicted on CT, MR, and US images. Similarly, there are numerous congenital and acquired disorders of the portal vein that are deleterious to its function and can be diagnosed by using imaging alone. Some of these conditions have subtle imaging features, and some are conspicuous at imaging but poorly understood or underrecognized. The authors examine imaging appearances of the portal vein, first by outlining the classic and variant anatomy and then by describing each of the disorders that impact portal vein function. The imaging appearances of portal vein abnormalities discussed in this review include (a) occlusion from and differentiation between bland thrombus and tumor in vein and the changes associated with resultant hepatic artery buffer response changes, cavernous transformation of the portal vein, and portal biliopathy; (b) ascending thrombophlebitis of the portal vein (pylephlebitis); (c) portal hypertension and its causes and sequelae; (d) the newly described disease entity portosinusoidal vascular disorder; and (e) intra- and extrahepatic shunts of the portal system, both congenital and acquired (including Abernethy malformations), and the associated risks. Current understanding of the pathophysiologic processes of each of these disorders is considered to aid the approach to reporting. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Breaking down tumor thrombus: Current strategies for medical management

Tumor thrombus, the intravascular extension of tumor into adjacent blood vessels, is frequently encountered in patients with renal cell carcinoma and hepatocellular carcinoma, and often involves the abdominal vasculature including the renal vein, portal vein, and the inferior vena cava. While a bland thrombus is composed of platelets and fibrin, in contrast, a tumor thrombus refers to an organized collection of tumor cells. Though oftentimes detected incidentally on imaging, tumor thrombus may have significant clinical implications and can be challenging to differentiate from bland thrombus. Additionally, the optimal management of tumor thrombus, including the use of anticoagulation, remains poorly described. This review summarizes common causes of tumor thrombus, as well as its impact on staging, prognosis, and treatment.

Body and Extremity MR Venography: Technique, Clinical Applications, and Advances

Magnetic resonance venography (MRV) represents a distinct imaging approach that may be used to evaluate a wide spectrum of venous pathology. Despite duplex ultrasound and computed tomography venography representing the dominant imaging modalities in investigating suspected venous disease, MRV is increasingly used due to its lack of ionizing radiation, unique ability to be performed without administration of intravenous contrast, and recent technical improvements resulting in improved sensitivity, image quality, and faster acquisition times. In this review, the authors discuss commonly used body and extremity MRV techniques, different clinical applications, and future directions.

Diagnostic experience of intravenous leiomyomatosis with emphasis on conventional ultrasonography imaging: a single-center study

Objective

Intravenous leiomyomatosis (IVL) is a rare and aggressive tumor type that has the potential to extend into the inferior vena cava (IVC) and is susceptible to be misdiagnosed and neglected. Despite its clinical significance, there is a paucity of research that has focused on the specific manifestations of IVL on ultrasonography. Therefore, this study aims to systematically analyze the specific ultrasound features of IVL and augment its diagnostic accuracy.

Materials and method

Prospective inclusion was granted to patients admitted to our hospital between December 2016 and March 2021 for an IVC-occupying lesion. Multi-modal ultrasonography, encompassing gray-scale and color Doppler, was conducted. Lesions were categorized as IVL or non-IVL based on pathological or follow-up data. Two ultrasound sonographers with over 5 years of experience read and recorded ultrasound data for all lesions, which were subsequently comparatively analyzed to identify specific signs of IVL.

Results

A total of 284 patients diagnosed with IVC-occupying lesions were included in the study. The lesion types comprised of IVL (n=67, 23.6%), IVC thrombus (n=135, 47.5%), tumor thrombus of renal carcinoma involving the IVC (n=35, 12.4%), tumor thrombus of liver carcinoma involving the IVC (n=24, 8.5%), leiomyosarcoma of the IVC (n=14, 4.9%), and tumor thrombus of adrenocortical adenocarcinoma (n=9, 4.1%). The presence of "sieve hole" and "multi-track" signs was observed in 20 IVL lesions under the grey-scale modality, while both signs were absent in the non-IVL group (P<0.01). The study found no statistically significant differences in the presentation of "sieve hole" and "multi-track" signs under the grey-scale and color Doppler modalities in cases of intravascular lithotripsy (IVL) (P>0.05). Using these two signs as diagnostic criteria for IVL, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), miss rate, misdiagnosis rate, and accuracy were determined to be 29.9%, 100%, 100%, 82.2%, 70.1%, 0, and 83.5%, respectively (AUC ROC=0.649; 95%CI: 0.537-0.761).

Conclusion

IVL exhibits distinct ultrasound presentations, including "sieve hole" and "multi-track" signs, which demonstrate high specificity and accuracy as diagnostic indicators. Furthermore, these signs are corroborated by pathological evidence and effectively distinguish IVL from other lesions occupying the IVC.

Diagnostic value of contrast-enhanced ultrasound in intravenous leiomyomatosis: a single-center experiences

Objective

Intravenous leiomyomatosis (IVL) is a rare disease, and few studies have focused on the diagnostic value of contrast-enhanced ultrasound (CEUS) in this condition. This study aimed to investigate the diagnostic value of CEUS in IVL and summarize the specific CEUS characteristics of IVL.

Materials and Method

From December 2016 to March 2021, 93 patients admitted to our hospital with inferior vena cava (IVC) occupying lesions were prospectively enrolled and underwent detailed ultrasound multi-modality examinations, including conventional and contrast-enhanced ultrasound scans. The diagnostic value of CEUS and conventional ultrasound (CU) in IVL was compared, and the specific IVL signs were summarized.

Results

Among the 93 patients with inferior vena cava mass, 67 were IVL while 26 were non-IVL. The inter-observer agreement of the two senior doctors was good, with Kappa coefficient = 0.71 (95% CI: 0.572–0.885). The area under the ROC curve of CU for IVL diagnosis was 0.652 (95% CI: 0.528–0.776), and its sensitivity, specificity, accuracy, positive predictive value, negative predictive value, missed diagnosis rate, and misdiagnosis rate were 61.1%, 69.2%, 63.4%, 83.7%, 40.9%, 38.8%, and 30.8%, respectively. The area under curve (AUC) for IVL diagnosis by CEUS was 0.807 (95% CI: 0.701–0.911), and the sensitivity, specificity, accuracy, positive predictive value, negative predictive value, missed diagnosis rate, and misdiagnosis rate were 82.0%, 84.6%, 82.8%, 93.2%, 64.7%, 15.4%, and 17.9%, respectively. In CEUS mode, “sieve hole sign” and “multi-track sign” were detected in 57 lesions, and the detected rate was higher than that of CU (https://loop.frontiersin.org/people/1014187 < 0.01).

Conclusion

CEUS can better show the fine blood flow inside the IVL, which is important for IVL differential diagnosis. Moreover, CEUS can obtain more information about IVL diagnosis than CU, compensating for the shortcomings of CU in detecting more blood flow within the lesion. Thus, this technique has great significance for IVL diagnosis.

Anormal uterin kanama ile seyreden tümör trombüsünün nadir bir nedeni olarak uterin leiomyomatozis

Anormal uterin kanama ile seyreden tümör trombüsünün nadir bir nedeni olarak uterin leiomyomatozis

Role of anticoagulation in the management of tumor thrombus: A 10-year single-center experience

BACKGROUND

Children with cancer diagnosis are overall at a higher risk of thrombosis. For a newly diagnosed blood clot, patients are commonly started on anticoagulants to prevent further extension and embolization of the clot. In the rare instance that a pediatric patient has a tumor thrombus, role of anticoagulation is less clear.

PROCEDURE/METHODS

Patients under 21 years of age with a finding of tumor thrombus on imaging from 2010 to 2020 at Texas Children's Hospital were identified and their medical records were reviewed.

RESULTS

A total of 50 patients were identified. Most thrombi were incidental findings at diagnosis; however, two patients presented with pulmonary embolism (PE). Inferior vena cava extension was noted in 36% of the patients, and 24% patients had an intracardiac tumor thrombus. Anticoagulation was initiated in 10 patients (20%). There was no difference in the rate of bland thrombus formation and/or embolization in patients who did or did not receive anticoagulation. However, three of the six patients with asymptomatic tumor thrombus who were started on anticoagulation had bleeding complications compared to only two patients in the no anticoagulation cohort (p < .05).

CONCLUSION

Children with intravascular extension of solid tumors were not commonly started on anticoagulation at the time of diagnosis, irrespective of the extent of tumor thrombus. Furthermore, we observed a significant trend toward higher incidence of bleeding complications after initiation of anticoagulation for asymptomatic tumor thrombus. There is inadequate evidence at this time to support routine initiation of anticoagulation in pediatric patients with intravascular extension of solid tumors.

Atrial cholangiocarcinoma diagnosed by cardiac magnetic resonance imaging

In this rare case of intrahepatic cholangiocarcinoma (ICC) tumor thrombus with right atrial (RA) invasion, we describe its diagnostic workup based on cardiac magnetic resonance imaging (cMRI). An 85-year-old man underwent transthoracic echocardiography due to dyspnea, revealing a RA mass. Comprehensive cMRI evaluation, including cine bright blood, T1- and T2-weighed, fat-suppressed, and contrast-enhanced imaging, was performed and diagnosis of ICC tumor thrombus with RA invasion was made. This first description of cMRI-guided diagnosis of RA invasion by ICC tumor thrombus points out the usefulness of cMRI for the diagnostic approach of RA masses suggestive of tumor thrombus.