Haemangiopericytoma: histological spectrum, immunohistochemical characterization and prognosis

Abstract

Canine haemangiopericytoma (CHP) is a vascular neoplasm thought to be derived from pericytes. The histological pattern and immunohistochemical profile were studied in 31 CHPs. Twenty-three subjects were followed for 2 years to evaluate the correlation among tumour location, histotype, immunostaining and outcome of the disease. Of the 31 CHPs examined, 20 exhibited a perivascular whorled pattern, 8 were storiform and 3 were epithelioid. All tumours were positive for vimentin and negative for cytokeratin, factor VIII-related antigen, glial fibrillary acidic protein and S-100 protein. Seventeen CHPs were positive for actin and nine co-expressed desmin. Six CHPs were also positive for CD34 antigen. The panel of immunohistochemical markers used confirmed the vascular lineage of CHP and aided in the exclusion of other mesenchymal tumours. Of the 23 dogs submitted to follow-up, 6 had recurrence or metastases of the primary tumour. The epithelioid pattern or a noncutaneous location were associated with a poorer prognosis.

Cutaneous Smooth Muscle Tumors in the Dog and Cat

“…10,18,20,24,29 The absence of labeling for these two markers does not definitively rule out a diagnosis of leiomyosarcoma. Also, other canine spindle cell tumors, such as hemangiopericytomas 14,19 and a variety of tumors in humans (including primitive neuroectodermal tumors, neuroblastomas, giant cell tumors of tendon sheaths, mesotheliomas, tumors of myofibroblast origin, and osteosarcomas), have been reported to express ␣-SMA and/or desmin. 5 Thus, a diagnosis of leiomyosarcoma cannot rely exclusively on positive labeling for these markers.…”

Hemangiopericytoma in a cat: a case report

“…In humans and dogs, essential differential diagnoses for HEP include peripheral nerve sheath tumour, fibrosarcoma, histiocytic sarcoma, vascular neoplasms, perivascular wall tumours and glomus tumours (Henderson et al 1986;Enzinger and Weiss 1995;Sawamoto et al 1999;Mazzei et al 2002;Chijiwa et al 2004;Gross et al 2005;Baldi and Spugnini 2006;Avallone et al 2007). In particular, the differentiation of HEP from peripheral nerve sheath tumours (PNST) can be difficult, since neoplastic cells in PNSTs may display similar morphological features as in HEPs, and are often arranged in whorls.…”

“…HEPs are solely found to consistently stain positive for vimentin. The immunoreactivity of HEPs for cytoskeletal and contractile proteins (desmin, alpha smooth muscle actin, calponin, panactin), neural markers (S-100 protein, glial fibrillary acidic protein, neuron specific enolase), cell surface proteins (CD34 and CMG-3G5), or markers of extracellular matrix proteins (laminin) however, has been reported to be highly variable and discordant ( Enzinger and Weiss 1995;Handharyani et al 1999;Sawamoto et al 1999;Goldschmidt and Hendrick 2002;Mazzei et al 2002;Chijiwa et al 2004;Gross et al 2005;Avallone et al 2007). Ultrastructurally, the neoplastic cells in (C) HEPs are commonly separated by variable amounts of intervening extracellular collagen fibres and form complex interdigitating processes of inconsistent length with the formation of variable numbers of intermediate desmosome-like intercellular junctions.…”

Relationship between DNA Ploidy and Proliferative Cell Nuclear Antigen Index in Canine Hemangiopericytoma

“…13,19 The typical histopathologic pattern of CHP is a whirling cellular configuration around a central vessel, the so-called ''fingerprint'' pattern. 4,10,20 This pattern is considered to be a distinctive characteristic of CHP and is a histologic feature used to differentiate CHP from some other soft-tissue neoplasms such as dermatofibrosarcomas and schwannomas. 4,10,20 Since CHP has frequent local recurrence at the surgical site but rarely metastasizes, the tumor is classified as lowgrade, soft-tissue sarcoma.…”

“…4,10,20 This pattern is considered to be a distinctive characteristic of CHP and is a histologic feature used to differentiate CHP from some other soft-tissue neoplasms such as dermatofibrosarcomas and schwannomas. 4,10,20 Since CHP has frequent local recurrence at the surgical site but rarely metastasizes, the tumor is classified as lowgrade, soft-tissue sarcoma. 1,8 The mitotic index is reported to be correlated with recurrence, mean patient survival, and metastasis of CHP.…”