Masson's “vegetant intravascular hemangioendothelioma:” a lesion often mistaken for angiosarcoma.Study of seventeen cases located in the skin and soft tissues

Abstract

The occurrence of Masson's "hemangio-endotheliome vegetant intravasculaire" (Masson's pseudoangiosarcoma) in the skin and soft tissues is illustrated with 17 surgically excised specimens. Two forms are recognized; it may appear either as a pure lesion or as a focal condition in a pre-existing vascular process, such as pyogenic granuloma or hemangioma. The clinical appearance is not specific and the diagnosis can only be established by microscopic examination. It shows a predilection for the head and extremities. Its characteristic morphologic appearance makes possible its differentiation from a group of benign and malignant vascular proliferations. The key microscopic feature is the presence of a papillary growth composed of hyperplastic endothelial cells supported by delicate fibrous stalks entirely confined within the vascular lumen. The lesion should not be mistaken for angiosarcoma, since its clinical behavior is invariably benign.

Intravascular Papillary Endothelial Hyperplasia Arising From the Upper Lip

“…It is characterized histologically by papillary fronds lined by proliferating endothelium 17) . IPEH is in fact the proliferation of endothelial cells or vascular malformation, the main significance of this intravascular endothelial hyperplasia is its microscopic resemblance to angiosarcoma and its possible misdiagnosis as such 3,7,10,17) . It is important to recognize such lesions histologically because they may mimic the appearance of angiosarcoma in their proliferation of endothelial cells, mitotic activity, and papillary projections.…”

Masson´s Tumor in the Maxillary Sinus

“…IPEH is known as a variety of synonyms including Masson's tumour, Masson's vegetant intravascular hemangioendothelioma and Masson's pseudoangiosarcoma intravascular angiomatosis [8]. The name "intravascular papillary endothelial proliferation," was given by Clearkin & Enzinger [5].…”

“…The name "intravascular papillary endothelial proliferation," was given by Clearkin & Enzinger [5]. IPEH is more frequent in females, suggesting that a hormonal role could be involved [5,8,13,14]. The mean age in one of the studies was 52.3 [13].…”

“…The histologic differential diagnosis of IPEH includes angiosarcoma, intravenous atypical vascular proliferation, spindle-cell hemangioendothelioma, malignant endovascular papillary angioendothelioma and intravenous pyogenic granuloma [14]. IPEH is completely intraluminal, it shows a close association with thrombotic material, lacks the piling up of endothelium, and does not show tissue necrosis, marked cellular pleomorphism, or a high mitotic rate [5][6][7][8]10,[14][15][16]]. The extremely rare extra vascular forms of papillary endothelial proliferation developing from organizing hematomas lack the irregular anastomosing channels and the malignant cytological features, and tend to be well circumscribed [15].…”

“…Considering the clinic course and pathological features similarities, IPEH mimics an angiosarcoma [4][5][6][7][8]. Histopathological analysis is mandatory to avoid misdiagnosis.…”