Intravascular papillary endothelial hyperplasia: report of two cases

Intravascular papillary endothelial hyperplasia: magnetic resonance imaging of finger lesions

OBJECTIVE

To describe magnetic resonance imaging (MRI) features of intravascular papillary endothelial hyperplasia (IPEH), to identify findings differentiating IPEH of the finger from that of other locations, and to correlate these with pathology.

MATERIALS AND METHODS

Nineteen patients with 20 I.E. masses of the finger (n = 13) and other locations (n = 7) were evaluated. All patients underwent MRI, and the results were correlated with pathology.

RESULTS

Seventeen IPEHs, including all IPEHs of the finger, were located in the subcutis, the three other lesions in the muscle layer. On T1WI, all masses were isointense or slightly hyperintense. IPEHs of the finger (n = 13) revealed focal hyperintense nodules (n = 2) or central hypointensity (n = 2) on T1WI, hypointensity with a hyperintense rim (n = 7), hyperintensity with hypointense nodules (n = 5), or isointensity with a hypointense rim (n = 1) on T2WI, and rim enhancement (n = 5), heterogeneous enhancement with nodular nonenhanced areas (n = 6), peripheral nodular enhancement (n = 1), or no enhancement (n = 1) on gadolinium-enhanced T1WI. IPEHs of other locations (n = 7) demonstrated focal hyperintense nodules (n = 5) on T1WI, hyperintensity with hypointense nodules (n = 5) or heterogeneous signal intensity (n = 2) on T2WI, and rim or rim and septal enhancement (n = 6) or peripheral nodular enhancement (n = 1). Microscopically, IPEHs were composed of thrombi that were hypointense on T2WI and papillary endothelial proliferations that showed T2 hyperintensity and enhancement.

CONCLUSION

MRI of finger IPEH reveals well-demarcated subcutaneous masses with hypointensity or hypointense nodules with peripheral hyperintensity on T2WI, as well as peripheral enhancement. T1 hyperintense nodules, internal heterogeneity on T2WI, and septal enhancement are more common in IPEH of other locations.

Intravascular papillary endothelial hyperplasia (Masson tumor) mimicking a sarcoma and developing from an arteriovenous hemodialysis fistula

Intravascular papillary endothelial hyperplasia (IPEH), also known as Masson's tumor, is a rare nonneoplastic vascular lesion caused by the abnormal proliferation of endothelial cells. Clinically and radiologically, IPEH presents as a soft tissue mass that may simulate and be mistaken for a sarcomatous tumor. There have been reports of this entity involving the skin or subcutaneous tissues in normal blood vessels and vascular malformations. Herein, we present the first reported case of Masson's tumor arising from an arteriovenous hemodialysis fistula. We emphasize the imaging features of this lesion and briefly discuss its pathophysiology.

Radiological imaging of florid intravascular papillary endothelial hyperplasia in the mandibule: case report and literature review

Intravascular papillary endothelial hyperplasia was a rare benign vascular proliferative process as a result of papillary proliferation of the endothelial cells within the vessels. To our knowledge, we reported the second case occurring in the madibule, and the first reported in 1984 in the literature. We discussed manifestations of multislice computed tomography and panoramic radiography about the lesion and relevant literature was reviewed.

Intravascular papillary endothelial hyperplasia of the digit: MRI features with histological correlation

To clarify the magnetic resonance (MR) features of the pure form of intravascular papillary endothelial hyperplasia, MR images (MRIs) from five patients were retrospectively reviewed and compared with histological findings. The images showed a heterogeneous, iso- to slightly high signal intensity mass on T1-weighted images and a mass with a central heterogeneous, iso- to slightly high signal intensity area completely or incompletely surrounded by peripheral high signal intensity areas on T2-weighted images. Heterogeneous enhancement was observed after gadolinium administration. Histological studies indicated that the central heterogeneous area on T2-weighted images corresponded to thrombi (organized and/or hyalinized) and/or papillary endothelial proliferation, and also that the peripheral high signal intensity area corresponded to vascular blood space and/or papillary endothelial proliferation. The pure form of intravascular papillary endothelial hyperplasia showed relatively characteristic features on MRIs.