title: Histological evaluation of the possible transformation of peripheral giant cell granuloma and peripheral ossifying fibroma: A preliminary study.
abstract: OBJECTIVE
  The objective of this study is to describe shared morphological features of peripheral giant cell granuloma (PGCG) and peripheral ossifying fibroma (POF) in detail and discuss the possible relationship between them.
  
  
  METHODS
  Ten intermediate cases with features resembling to both POF and PGCG were selected and type 3 and 1 collagen immunostainings were performed for evaluation of the connective tissue maturation. Immunohistochemical staining percentage (SP) for stromal cells in the slides of POF and PGCG counterparts of intermediate lesions was scored as 1 when the SP was above 10%, 2 when the SP was above 25%, 3 when the SP was above 50% and 4 when the SP was above 75%. Staining intensity (SI) of immunuhistochemical staining was graded and scored as 1 - mild, 2 - moderate, and 3 - severe. An immunoreactivity score was calculated by multiplying SP and SI.
  
  
  RESULTS
  All intermediate lesions comprised osteoclast type multinucleated giant cells and partly mineralized hard tissue component. Parts of intermediate lesions resembling POF showed higher type 1 collagen immunoreactivity compared to the PGCG counterparts of intermediate lesions (P < 0.05). PGCG counterparts showed higher type 3 collagen immunoreactivity compared to the POF counterparts of the intermediate lesions (P < 0.05).
  
  
  CONCLUSIONS
  POF may be a later stage lesion with morphologically more mature components. A possible transformation may be considered for these two lesions.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Eskişehir Osmangazi University, Eskişehir, Turkey.
authors.forename: Ömür
authors.initials: Ö
authors.lastname: Dereci
authors.affiliation: Department of Periodontology, Faculty of Dentistry, Ankara University, Ankara, Turkey.
authors.forename: Şivge
authors.initials: Ş
authors.lastname: Akgün
authors.affiliation: Gören Private Pathology Labratory, Private Gören Pathology Institution, Ankara, Turkey.
authors.forename: Bülent
authors.initials: B
authors.lastname: Celasun
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ankara University, Ankara, Turkey.
authors.forename: Adnan
authors.initials: A
authors.lastname: Öztürk
authors.affiliation: Department of Pathology, Gülhane Military Medical Academy, Ankara, Turkey.
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Günhan
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D024042:Collagen Type I / Q000032:analysis; D024061:Collagen Type III / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D018214:Fibroma, Ossifying / Q000175:diagnosis* / Q000473:pathology*; D006101:Granuloma, Giant Cell / Q000175:diagnosis* / Q000473:pathology*; D006651:Histocytochemistry; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008853:Microscopy; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D024042:Collagen Type I; D024061:Collagen Type III