title: Argyrophilic nucleolar organizer regions in inflammatory, premalignant, and malignant oral lesions: a quantitative and qualitative assessment.
abstract: OBJECTIVE
  Argyrophilic nucleolar organizer regions (AgNORs) have found widespread application in the past, especially in tumor histopathology. This study was undertaken to evaluate the significance of various AgNOR parameters and to assess their role in differentiating hyperplastic, premalignant, and malignant lesions.
  
  
  METHODS
  The study sample consisted of archival biopsy specimens of ten squamous cell carcinomas, ten premalignant lesions, and five inflammatory lesions. Two biopsies from normal mucosa acted as control. AgNORs were assessed both quantitatively and qualitatively. The data were analyzed using Student's independent t-test, one-way analysis of variance (ANOVA), and multiple range test (Tukey-HSD).
  
  
  RESULTS
  Quantitatively significant difference existed in the number of AgNORs between the normal mucosa, inflammatory lesions, and carcinomas, but the premalignant lesions failed to differ significantly from the normal mucosa. The number of AgNORs was found to be related to epithelial proliferation. Qualitatively, in terms of size, shape, and pattern of distribution, the normal mucosa and inflammatory lesion were alike, but the premalignant and malignant lesions differed significantly from the normal, with a marked degree of AgNOR pleomorphism being observed in carcinomas.
  
  
  CONCLUSIONS
  AgNOR quantity is strictly proportional to the proliferative activity of the cell and does not necessarily indicate malignancy. It is the qualitative characteristics of AgNOR that help to differentiate hyperplastic, premalignant, and malignant lesions.
authors.affiliation: Department of Oral and Maxillofacial Pathology, Sri. Ramachandra Dental College and Hospital, Sri. Ramachandra University, Porur, Chennai, Tamil Nadu, India. drelang@yahoo.co.in
authors.forename: T
authors.initials: T
authors.lastname: Elangovan
authors.forename: N J
authors.initials: NJ
authors.lastname: Mani
authors.forename: N
authors.initials: N
authors.lastname: Malathi
mesh_terms: D034961:Antigens, Nuclear / Q000032:analysis; D014408:Biomarkers, Tumor; D002294:Carcinoma, Squamous Cell / Q000737:chemistry / Q000473:pathology*; D049109:Cell Proliferation; D003937:Diagnosis, Differential; D017789:Granuloma, Pyogenic / Q000473:pathology; D006801:Humans; D007972:Leukoplakia, Oral / Q000737:chemistry / Q000473:pathology*; D009059:Mouth Diseases / Q000473:pathology; D009061:Mouth Mucosa / Q000737:chemistry / Q000166:cytology; D009062:Mouth Neoplasms / Q000737:chemistry / Q000473:pathology*; D009697:Nucleolus Organizer Region / Q000473:pathology*; D011230:Precancerous Conditions / Q000737:chemistry / Q000473:pathology*; D016622:Silver Staining
chemical_list: D034961:Antigens, Nuclear; D014408:Biomarkers, Tumor; C051963:nucleolar organizer region associated proteins