Intravascular papillary endothelial hyperplasia

Intravascular
papillary endothelial hyperplasia • Pericavernous sinus Masson's tumor - Ganzer Fall bei Radiopaedia
Nelson R, Pericavernous sinus Masson's tumor. Case study, Radiopaedia.org (Accessed on 06 Jan 2023) https://doi.org/10.53347/rID-91289 • CC by-nc-sa 3.0 (modified)
Masson’s
tumour of the kidney. Contrast-enhanced CT, venous phase. A heterogenous lesion is seen in the sinus of the left kidney.
cancerimagingjournal.biomedcentral.com • Open Access
Masson’s
tumour of the kidney. T1-weighted (TE 4.2 msec/TR 7.7 msec) image, axial plane. The tumor is hypointense compared to the renal cortex.
cancerimagingjournal.biomedcentral.com • Open Access
Masson’s
tumour of the kidney. (a) T2-weighted (TE 60 msec/TR 4.3 msec) image, coronal plane. The lesion abuts the renal pelvis and is predominantly hyperintense; some intralesional hypointense strands are present, fading out from the medial border of the tumor. (b) Heavily T2-weighted image (TE 378 msec/TE 4.3 msec). The tumor is less intense than the content of the renal pelvis; the intralesional hypointense strands are seen more clearly.
cancerimagingjournal.biomedcentral.com • Open Access
Masson’s
tumour of the kidney. 3D contrast-enhanced MR-angiography, coronal plane, corticomedullary phase. The lesion is slightly hypovascular compared to the renal cortex.
cancerimagingjournal.biomedcentral.com • Open Access
nicht verwechseln mit: Dyke Davidoff Masson syndrome
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Intravascular papillary endothelial hyperplasias, also known as Masson tumors, are rare non-neoplastic vascular proliferations.

Clinical presentation

Patients usually present with an enlarging soft tissue mass .

Pathology

The lesion is a reactive process characterized by endothelial cell proliferation in the setting of venous stasis commonly associated with thrombosis. The pure form consists of organized thrombus limited to the vascular lumen. The mixed form arises in the setting of a pre-existing vascular lesion such as hemangioma.

Radiographic features

MRI

Lesions are most commonly located in subcutaneous soft tissues and associated with a visible origin vessel. They are usually small (<2 cm), well-defined, round or oval, and heterogeneous in signal .

  • T1: iso- to slightly hyperintense, with nodular foci of high signal intensity
  • T2: hyperintense peripherally, with nodular foci of low signal intensity
  • T1 C+: peripheral/septal or central enhancement

Treatment and prognosis

The treatment is surgical resection. The pure form of intravascular papillary endothelial hyperplasia carries no risk of recurrence when completely resected.

Differential diagnosis

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