Sinonasal Hemangiopericytoma: DNA Content and Pathological Features

Abstract

Hemangiopericytomas are rare vasoformative tumors representing varied clinical courses and histology. Sinonasal hemangiopericytomas (SNHP) are thought to be low grade malignancies with possible late local recurrences and rare metastases even after therapy. We present four cases of SNHP and evaluate the pathological features of diagnostic and prognostic significance. Our cases are compared with all previously reported SNHP series. Cases were retrieved from medical records from our teaching institutions for the last 20 years. Clinical presentation, course, and pathology were reviewed in all cases. DNA content by image analysis, proliferation antigen (MIB-1), estrogen and progesterone receptor status, and other immunohistochemical markers were performed. All patients were females with mean age at presentation of 48.5 (18–77) years. Initial therapy was surgery alone or in combination with radiation therapy. Three patients had local recurrences at 5, 9, and 10 years, one of whom died of metastatic disease 11 years after diagnosis. DNA analysis revealed that three patients had diploid tumors. The patient who died of metastatic disease had a large aneuploid population. The proliferative fraction of the tumors studied with MIB-1 was less than 5% in all tumors. Estrogen receptors were negative in all tumors, and two tumors showed 10% positivity for progesterone receptors. All tumors stained positively with antibodies to vimentin and variably positive with smooth muscle actin. SNHP patients require life-long follow-up because of possible late recurrences and the potential for metastasis. DNA content may be useful for identifying malignant potential.