title: Immunohistochemical expression of pRb in pleomorphic adenoma and carcinoma ex pleomorphic adenoma.
abstract: OBJECTIVE
  This study aimed to characterize alteration in the immunohistochemical expression of pRb in normal tissue of the salivary gland surrounding pleomorphic adenoma, the tumor cells of pleomorphic adenomas, and carcinoma arising in pleomorphic adenoma.
  
  
  METHODS
  A selected series of 29 cases of pleomorphic adenomas, and 27 cases of carcinoma ex-pleomorphic adenoma (undifferentiated and adenocarcinoma types) were examined.
  
  
  RESULTS
  The results showed that pRb expression was negative in the components of normal tissue of the salivary gland surrounding pleomorphic adenoma. PRb expression in pleomorphic adenomas shows that 2 cases out of 29 (6.9%) strongly expressed in the duct cells, 7/29 (24.1%) cases showed moderate staining. pRb nuclear staining in myxochondroid was identified in 10/29 (34.5%) cases of pleomorphic adenomas with weak staining, 6/29 (20.7%) with moderate staining. pRb was strongly expressed in carcinoma cells in 19 out of 27 cases (70.4%).
  
  
  CONCLUSIONS
  This study suggests the alteration of pRb expression would increase from pleomorphic adenoma to carcinoma arising in pleomorphic adenomas (6.9% versus 70.4%).
authors.affiliation: Faculty of Dentistry, Aleppo University, Aleppo, Syria. denpol@yahoo.co.uk
authors.forename: Bassel
authors.initials: B
authors.lastname: Tarakji
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000378:metabolism*; D008949:Adenoma, Pleomorphic / Q000737:chemistry / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016160:Retinoblastoma Protein / Q000032:analysis / Q000096:biosynthesis*; D012468:Salivary Gland Neoplasms / Q000737:chemistry / Q000378:metabolism*; D055815:Young Adult
chemical_list: D016160:Retinoblastoma Protein