IS IT BENIGN OR MALIGN TUMOR ? MORPHOLOGİCAL AND IMMUNOCHEMICAL PROPERTİES SUITABLE WITH TYPE B2 THYMOMA. MEDİASTİNUM. MASS EXCİSİON -Tumor size 13 cm. -Capsule was observed around the tumor. Focal capsule invasion was seen. -Lymphavascular and perineural tumor invasion was absent. -Normal thymus tissue is seen in non tumoral adipose tissue.