Tumors in von Hippel–Lindau Syndrome: From Head to Toe—Comprehensive State-of-the-Art Review

Von Hippel–Lindau syndrome (VHL) is an autosomal-dominant hereditary tumor disease that arises owing to germline mutations in the VHL gene, located on the short arm of chromosome 3. Patients with VHL may develop multiple benign and malignant tumors involving various organ systems, including retinal hemangioblastomas (HBs), central nervous system (CNS) HBs, endolymphatic sac tumors, pancreatic neuroendocrine tumors, pancreatic cystadenomas, pancreatic cysts, clear cell renal cell carcinomas, renal cysts, pheochromocytomas, paragangliomas, and epididymal and broad ligament cystadenomas. The VHL/hypoxia-inducible factor pathway is believed to play a key role in the pathogenesis of VHL-related tumors. The diagnosis of VHL can be made clinically when the characteristic clinical history and findings have manifested, such as the presence of two or more CNS HBs. Genetic testing for heterozygous germline VHL mutation may also be used to confirm the diagnosis of VHL. Imaging plays an important role in the diagnosis and surveillance of patients with VHL. Familiarity with the clinical and imaging manifestations of the various VHL-related tumors is important for early detection and guiding appropriate management. The purpose of this article is to discuss the molecular cytogenetics and clinical manifestations of VHL, review the characteristic multimodality imaging features of the various VHL-related tumors affecting multiple organ systems, and discuss the latest advances in management of VHL, including current recommendations for surveillance and screening

Imaging features of rare mesenychmal liver tumours: beyond haemangiomas.

Tumours arising from mesenchymal tissue components such as vascular, fibrous and adipose tissue can manifest in the liver. Although histopathology is often necessary for definitive diagnosis, many of these lesions exhibit characteristic imaging features. The radiologist plays an important role in suggesting the diagnosis, which can direct appropriate immunohistochemical staining at histology. The aim of this review is to present clinical and imaging findings of a spectrum of mesenchymal liver tumours such as haemangioma, epithelioid haemangioendothelioma, lipoma, PEComa, angiosarcoma, inflammatory myofibroblastic tumour, solitary fibrous tumour, leiomyoma, leiomyosarcoma, Kaposi sarcoma, mesenchymal hamartoma, undifferentiated embryonal sarcoma, rhabdomyosarcoma and hepatic metastases. Knowledge of the characteristic features of these tumours will aid in guiding the radiologic diagnosis and appropriate patient management

Outcomes of percutaneous endovascular intervention for type II endoleak with aneurysm expansion

ObjectiveType II endoleak (T2EL) with aneurysm expansion is believed to place patients at risk for aneurysm-related mortality (ARM). Treatment with glue and/or coil embolization of the aneurysm sac, inferior mesenteric artery (IMA), and lumbar branches via translumbar or transarterial approaches has been utilized to ablate such endoleaks, and thus decrease ARM. We evaluated the midterm results of percutaneous endovascular treatment of T2EL with aneurysm expansion.MethodsSingle-institution, 5-year (January 2003 to August 2008) retrospective study of all endovascular interventions for T2EL with sac expansion. Blinded, independent review of all available pre- and post-T2EL intervention computed tomography (CT) scans was performed. Aneurysm sac maximal transverse diameters and aneurysm sac growth rates prior to and following T2EL intervention were analyzed.ResultsForty-two patients (34 male, eight female; mean age, 75) underwent T2EL intervention at 26 ± 20 months after endovascular aneurysm repair (EVAR) and were subsequently followed for 23 ± 20 months. Seven out of 42 patients (17%) underwent repeat T2EL intervention. Interventions included 44 translumbar sac embolizations, and transcatheter embolizations of nine IMAs and seven lumbar/hypogastric arteries. Aneurysm diameter was 6.1 ± 1.6 cm at EVAR, 6.6 ± 1.5 cm at initial T2EL treatment, and 6.9 ± 1.7 cm at last follow-up. There were no significant differences in the rates of aneurysm sac growth pre- and post-T2EL treatment. At last follow-up imaging, recurrent or persistent T2EL was noted in 72% of patients. Of 42 patients, nine (21%) received operative endoluminal correction of occult type I or type III endoleaks that were diagnosed during the T2EL angiographic intervention. There were no aneurysm ruptures or ARMs during follow-up; overall mortality for the 5-year study period was 24%.ConclusionsIn this series, percutaneous endovascular intervention for type II endoleak with aneurysm sac growth does not appear to alter the rate of aneurysm sac growth, and the majority of patients display persistent/recurrent endoleak. However, diagnostic angiographic evaluation may reveal unexpected type I and III endoleaks and is therefore recommended for all patients with T2EL and sac growth. While coil and glue embolization of aneurysm sac and selected branch vessels does not appear to yield benefit in our series, the diagnosis and subsequent definitive treatment of previously occult type I and III endoleaks may explain the absence of delayed rupture and ARM in our series

Chemotherapy-associated liver morphological changes in hepatic metastases (CALMCHeM)

PURPOSETo review imaging findings in chemotherapy-associated liver morphological changes in hepatic metastases (CALMCHeM) on computed tomography (CT)/magnetic resonance imaging (MRI) and its association with tumor burden.METHODSWe performed a retrospective chart review to identify patients with hepatic metastases who received chemotherapy and subsequent follow-up imaging where CT or MRI showed morphological changes in the liver. The morphological changes searched for were nodularity, capsular retraction, hypodense fibrotic bands, lobulated outline, atrophy or hypertrophy of segments or lobes, widened fissures, and one or more features of portal hypertension (splenomegaly/venous collaterals/ascites). The inclusion criteria were as follows: a) no known chronic liver disease; b) availability of CT or MRI images before chemotherapy that showed no morphological signs of chronic liver disease; c) at least one follow-up CT or MRI image demonstrating CALMCHeM after chemotherapy. Two radiologists in consensus graded the initial hepatic metastases tumor burden according to number (≤10 and >10), lobe distribution (single or both lobes), and liver parenchyma volume affected (10 in 64.4% of patients. The volume of liver involved was <50% in 79.8% and ≥50% in 20.2% of cases. The severity of CALMCHeM at the first imaging follow-up was associated with a larger number of metastases (P = 0.002) and volume of the liver affected (P = 0.015). The severity of CALMCHeM had progressed to moderate to severe changes in 85.9% of patients, and 72.5% of patients had one or more features of portal hypertension at the last follow-up. The most common features at the final follow-up were nodularity (95.0%), capsular retraction (93.4%), atrophy (66.2%), and ascites (65.7%). The Cox proportional hazard model showed metastases affected ≥50% of the liver (P = 0.033), and the female gender (P = 0.004) was independently associated with severe CALMCHeM.CONCLUSIONCALMCHeM can be observed with a wide variety of malignancies, is progressive in severity, and the severity correlates with the initial metastatic liver disease burden

Accuracy of CT Colonography for Detection of Large Adenomas and Cancers

Background Computed tomographic (CT) colonography is a noninvasive option in screening for colorectal cancer. However, its accuracy as a screening tool in asymptomatic adults has not been well defined. Methods We recruited 2600 asymptomatic study participants, 50 years of age or older, at 15 study centers. CT colonographic images were acquired with the use of standard bowel preparation, stool and fluid tagging, mechanical insufflation, and multidetector-row CT scanners (with 16 or more rows). Radiologists trained in CT colonography reported all lesions measuring 5 mm or more in diameter. Optical colonoscopy and histologic review were performed according to established clinical protocols at each center and served as the reference standard. The primary end point was detection by CT colonography of histologically confirmed large adenomas and adenocarcinomas (10 mm in diameter or larger) that had been detected by colonoscopy; detection of smaller colorectal lesions (6 to 9 mm in diameter) was also evaluated. Results Complete data were available for 2531 participants (97%). For large adenomas and cancers, the mean (±SE) per-patient estimates of the sensitivity, specificity, positive and negative predictive values, and area under the receiver-operating-characteristic curve for CT colonography were 0.90±0.03, 0.86±0.02, 0.23±0.02, 0.99± Conclusions In this study of asymptomatic adults, CT colonographic screening identified 90% of subjects with adenomas or cancers measuring 10 mm or more in diameter. These findings augment published data on the role of CT colonography in screening patients with an average risk of colorectal cancer. (ClinicalTrials.gov number, NCT00084929; American College of Radiology Imaging Network [ACRIN] number, 6664.

MRI characterization of 124 CT-indeterminate focal hepatic lesions: evaluation of clinical utility

Objective. To evaluate the diagnostic yield of MRI performed for characterization of focal hepatic lesions that are interpreted as indeterminate on CT. Patients and methods. In a retrospective investigation, 124 indeterminate focal hepatic lesions in 96 patients were identified on CT examinations over 5 years from 1997 to 2001. All patients had MRI performed for the liver within 6 weeks of their CT examination. CT and MR images were reviewed independently by two separate groups of two radiologists. The value of MRI in characterizing these lesions was assessed. Diagnoses were confirmed based on histology, characteristic imaging features, and clinical follow-up . Results. MRI definitely characterized 73 lesions (58%) that were indeterminate on CT. MRI was accurate in 72/73 of these lesions. MRI could not definitely characterize 51 lesions (42%). Ten lesions were not visualized on MRI, and follow-up imaging confirmed that no lesion was present in eight of these cases (pseudolesions). Conclusion. MRI is valuable for the characterization of indeterminate focal hepatic lesions detected on CT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75168/1/13651820701216950.pd

Virtual colonoscopy for colorectal cancer screening: current status: Wednesday 5 October 2005, 14:00–16:00

Computed tomography colonography (CTC) (also known as ‘virtual colonoscopy’) is a noninvasive method of imaging the colon using helical CT. Although CTC has been shown to be useful for certain clinical indications, it has not yet been endorsed as a colorectal cancer screening test. The purpose of this article is to review the current status of CTC for colorectal cancer screening. CTC is an accurate method to detect colonic polyps and to select patients who would benefit from colonoscopy. The major advantages of CTC over conventional colonography include its relatively low risk and greater tolerance by patients. In this article, the CTC procedure and results of clinical trials are reviewed, as well as potential pitfalls related to CTC performance and interpretation. Finally, radiation dose, the discovery of incidental extracolonic findings with CTC, bowel preparation methods, and computer-aided diagnosis are addressed