Caratterizzazione clinica, morfologica ed immunoistochimica dei tumori perivascolari del cane

Perivascular wall tumors (PWT) are neoplasms arising from mural cells of blood vessels excluding the endotheliallining. Human cutaneous PWT comprise glomus tumor, hemagiopericytoma (HEP), myopericytoma (MPC),angioleiomyoma/sarcoma, angiomyofibroblastoma and angiofibroma. On the contrary PWT described in dogs are HEP,angioleiomyoma/sarcoma and glomus tumor. The purpose of this study was to characterize canine cutaneous PWT.Twenty cases with cytology suggestive of HEP were included. Diagnosis was based on vascular histological growthpatterns (staghorn, placentoid, perivascular whorling, bundles from media) and immunohistology utilizing 22 markers,including 7 smooth muscle markers and the cell surface ganglioside recognized by 3G5 (CSG-3G5). All cases weresingle lesions with frequent acral location (10/20). Six MPC, 5 angioleiomyomas, 2 angioleiomyosarcomas, 2 HEP, 1angiofibroma and 1 adventitial tumor were identified. A definitive diagnosis was not possible in 3 cases. Smoothelin,caldesmon, desmin, myosin, calponin and 3G5 were the most valuable markers for the differential diagnosis of caninePWT. Similar to reports in man, canine HEP seems to be an uncommon and aggressive tumor. Prior to group caninePWT into one prognostic category an accurate classification and prognostic characterization seem necessary.[...