Oral Intravascular Papillary Endothelial Hyperplasia Associated with an Organizing Thrombus: Case Report and Immunohistochemical Analysis

An Uncommon Great Pretender in Oral Cavity Lesions: The Masson's Tumor

Intravascular papillary endothelial hyperplasia (IPEH) is a rare benign non-neoplastic vascular lesion. A typical presentation consists of a subcutaneous nodule that may simulate other clinical entities. Presentation in the oral cavity is uncommon. It is thought to develop as an abnormal proliferative reaction of endothelial cells in a process of impaired thrombogenesis. When endothelial proliferation occurs, a differential diagnosis with a soft tissue sarcoma, in particular an angiosarcoma, should be performed. We report a case of a 68-year-old female patient who presented with a lesion on the upper lip of 3 months' duration. Surgical resection revealed an IPEH. 1 year later, the patient showed a local recurrence requiring excision with clear margins. Pathological and immunohistochemical features can help us distinguish these lesions from those requiring more aggressive treatment. The gold standard is surgical resection with clear margins. Accurate preoperative diagnosis is essential to avoid overtreatment. Emphasis should be placed on clinical, radiological and histological studies.

Periocular intravascular papillary endothelial hyperplasia: A retrospective study

INTRODUCTION

Intravascular papillary endothelial hyperplasia (IPEH) is a rare proliferation of endothelial cells with uncertain etiology related to thrombus formation. Diagnosis is usually confirmed histopathologically. This condition has been previously described in the periocular region but not in the conjunctiva.

METHODS

It is a retrospective case series in which we evaluated seven patients with histopathologically confirmed IPEH cases. Data regarding the demographics, clinical presentation, radiological description, histopathological features including any IHC staining, suspected underlying vascular etiology, management options, and follow up outcome were collected.

RESULTS

A total of seven cases of histologically confirmed IPEH were included. Five out of seven patients were male (71.4%). The age range was between 6 and 69 years with a median age of 36 years. Three cases involved the eyelid (42.8%) and another three were found in the conjunctiva (42.8%). Pre-existing underlying vascular lesions were observed in all patients, five malformations (mostly lymphatic-venous) and two conjunctival hemorrhagic lymphangiectasis. All cases were treated with excisional biopsy with no signs of recurrence within an average of 7 months follow up.

CONCLUSIONS

Periocular IPEH is a rare tumor that is likely to coexist with underlying vascular lesions and thrombus formation. We are reporting its existence in the conjunctiva for the first time. Therefore, pathologists should be aware of the histopathological spectrum of this lesion.

Papillary Endothelial Hyperplasia (Masson Tumor) of the Hand. Surgical and Pathological Consideration from Seven Cases Using New Vascular Markers

Although papillary endothelial hyperplasia may occur at almost any site, one of the most common sites is the hand. It is generally regarded as a reactive vascular proliferation i.e. exuberant form of organizing thrombus. Diagnosis of Masson tumor can be challenging due to its close clinical, radiological and even histopathological resemblance to angiosarcoma. We present seven cases of Masson tumor of the hand; wanting to reveal its nature using new vascular markers and discuss the treatment options and expected outcomes, present clinical and radiological features that may aid diagnosis and also offer treatment plans. A multicenter retrospective study was performed between January 2014 and November 2019. Immunohistochemical stains of Glut1, WT1, ERG, CD31 and alpha smooth muscle actin (ASMA) were performed on each cases. We found seven cases during the examined period. 4 out of 7 cases were women. All lesions occurred in the hands. 3 out of 7 cases appeared in a previously present vascular malformation. All cases were treated with surgical excision and the diagnosis of papillary endothelial hyperplasia was made by histology. Pre-operative testing (radiograph/MRI/US/fine needle aspiration biopsy) did not suggest the diagnosis of Masson tumor; however, aspiration cytology could rule out malignancy. The proliferative endothelial cells proved to be Glut1 negative and WT1 positive and the accompanying pericytic cells were ASMA positive in all cases. Though Masson tumor is a rare vascular lesion in the hand among other vascular tumors, it should be considered in the differential diagnostics even in the case of previously existing vascular malformation. WT1 positivity of the endothelial cells and the accompanying pericytic cells raises the question whether the initially reactive endothelial proliferation may transform into a true benign vascular tumor.