bcl-2 expression in pleural and extrapleural solitary fibrous tumours.
This study evaluated the immunoreactivity for bcl-2, a molecule involved in the control of programmed cell death, in cases of pleural (14) and extrapleural (2) solitary fibrous tumour (SFT), malignant mesotheliomas of different histological types, and a variety of extrapleural CD34-positive and CD34-negative spindle-cell tumours. In all SFTs, strong and diffuse immunostaining was demonstrated with anti-bel-2 antibody, sharply contrasting with the complete lack of staining observed in all mesotheliomas. The specificity of immunodetection of bcl-2 in SFT was confirmed by immunoblot analysis, showing a band consistent with the bcl-2 protein. At extrapleural locations, strong bcl-2 immunoreactivity was observed in Schwannoma (2/3 cases), synovial sarcoma (4/4 cases), and all cases of CD34-positive gastrointestinal stromal tumour (GIST; 10/10 cases). Most sarcomas were bcl-2-negative. Lack of bcl-2 expression was demonstrated in tumours which can pose problems in the differential diagnosis of SFT and can exhibit haemangiopericytoma-like features, including haemangiopericytoma (3 cases), dermatofibrosarcoma protuberans (16 cases), and deep-seated fibrous histiocytoma (3 cases). The constitutive expression of bcl-2 in SFT widens the spectrum of available markers for these tumours, providing a useful adjunct to their differential diagnosis in difficult cases at pleural and extrapleural sites, and contributing to the understanding of their histogenesis and molecular pathogenesis.
Chilosi
M
M
Department of Pathology, University of Verona, Italy.
Facchettti
F
F
Dei Tos
A P
AP
Lestani
M
M
Morassi
M L
ML
Martignoni
G
G
Sorio
C
C
Benedetti
A
A
Morelli
L
L
Doglioni
C
C
Barberis
M
M
Menestrina
F
F
Viale
G
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015153:Blotting, Western; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008654:Mesothelioma / Q000175:diagnosis / Q000378:metabolism; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D018218:Neoplasms, Fibrous Tissue / Q000175:diagnosis / Q000378:metabolism*; D010997:Pleural Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D012983:Soft Tissue Neoplasms / Q000175:diagnosis / Q000378:metabolism
D018952:Antigens, CD34; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D019253:Proto-Oncogene Proteins c-bcl-2