Primary Pseudomyogenic Hemangioendothelioma of Bone

Abstract

Pseudomyogenic hemangioendothelioma (PMH) is a well-recognized neoplasm that usually arises in the soft tissue; concurrent bone involvement occurs in 24% of cases. PMH of bone without soft tissue involvement is rare. We describe the clinicopathologic findings of 10 such cases, the largest series reported to date. The study included 9 male and 1 female patient; their ages ranged from 12 to 74 years (mean 36.7 y). All patients had multiple tumors with a distinct regional distribution: 45% restricted to the lower extremity; 25% to the spine and pelvis; and 15% to the upper extremity. On imaging studies the tumors were well circumscribed and lytic. The neoplasms were composed of spindled cells arranged in intersecting fascicles with scattered epithelioid cells; epithelioid cells predominated in 3 cases. The neoplastic cells contained abundant densely eosinophilic cytoplasm and vesicular nuclei. There was limited cytologic atypia and necrosis, few mitoses (0 to 2/10 high-power fields), and inconspicuous stroma. Unique findings included abundant intratumoral reactive woven bone and hemorrhage with numerous osteoclast-like giant cells. Immunohistochemically, most tumors were positive for keratin, ERG, and CD31; CD34 was negative. The balanced t(7:19)(q22;13) translocation was documented in 3 cases. Follow-up is limited, but no patient developed documented visceral dissemination, and all have stable or progressive osseous disease. PMH exclusively involving bone is rare. It is multicentric, often involves the lower extremity, and has unusual morphology. The differential diagnosis includes epithelioid vascular neoplasms, giant cell tumor, bone forming neoplasms, and metastatic carcinoma. Because of its rarity, unusual presentation, and morphology, accurate diagnosis can be challenging.

Primary vascular bone tumors in the spine: a challenge for pathologists and spine oncology surgeons

“…The new classification of bone vascular tumors as proposed in 2013 is supported by the rapid elucidation of novel, characteristic translocations in the different entities [2]. In the last 4 years, there have been further several important refinements in the classification of vascular neoplasms of bone, including the description of vascular tumor types previous reported only in soft tissues such as Pseudomyogenic Hemangioendothelioma and Retiform Hemangioendothelioma, along with the identification of novel and recurrent molecular genetic findings, broadening the spectrum of available ancillary tests for the pathologist [1,2,7,[9][10][11][12][13].…”

“…3, 4, 5), as a low-grade malignancy and Angiosarcoma, as a high-grade malignant tumor. Pseudomyogenic and Retiform Hemangioendothelioma are soft tissue tumors, in very rare cases arising in bone [2,12]. A retrospective review was decided of the 65 cases of primary bone vascular tumors of the spine diagnosed before 2011 using the immunohistochemical and molecular analyses not available before.…”

ZFP36–FOSB fusion in a haemorrhagic epithelioid and spindle cell haemangioma of bone: is there a family of FOSB‐rearranged vascular neoplasms of the bone?

“…Firstly, osseous PHE also shows a propensity for regional multifocal bone involvement. 4,6,7 Secondly, strong and diffuse FOSB-and CK-immunoreactivity are also typical of PHE. 4,6 However, we found very few neoplastic vessels lined by tombstone-like endothelia, which is not compatible with the current classification of PHE being strictly defined as non-vasoformative.…”

Pseudomyogenic Hemangioendothelioma

“…Intraosseous tumors are usually multiple, well-delineated, lytic lesions with increased uptake and without a periosteal reaction or bone destruction. [7][8][9]…”