Thoracic Small Round Cell Tumors

There is a group of tumors share the same nuclear size <3 red blood cells and can be differentiated only by immunostaining. All thoracic small cells tumors diagnosed between 1998-2001 during 4 years, at AL ASSAD UNIVERSITY HOSPITAL – DAMASCUS UNIVERSITY. There were 103 cases (66 cases of small cell carcinoma, 30 malignant lymphoma, and 7 cases of PNET ). We performed the immunostaining in 31 cases of small cell carcinoma ,all of them were malignant lymphomas and the 7 cases of PNET*. PNET cannot be diagnosed without immunostaining. We must demand the immunostaining if there is a doubt ( clinical or pathological) about the real nature of a small cell tumor.