title: A peripheral giant cell granuloma with extensive osseous metaplasia or a hybrid peripheral giant cell granuloma-peripheral ossifying fibroma: a case report.
abstract: BACKGROUND
  Peripheral giant cell granuloma and peripheral ossifying fibroma are clinicopathologically distinct gingival lesions. Both are included in clinical differential diagnoses of common benign and reactive gingival epulides in humans. It is often impossible to make a clinical distinction between the two entities, thereby making definitive diagnosis dependent on histopathologic features. While our search of the English literature revealed several reports of peripheral giant cell granuloma with 'bone formation', we were unable to identify any reports of hybrid peripheral ossifying fibroma-peripheral giant cell granulomas.
  
  
  METHODS
  We report a case of a 44-year-old Caucasian man presenting with a three-month history of swelling of his right posterior mandible, related to an area of previous dental implant restoration. A clinical examination revealed modest extraoral facial swelling of his right posterior mandible, while an intraoral examination showed a 45 × 25 × 15 mm sessile, lobular soft tissue mass of the right posterior mandibular gingiva. The mucosal covering of the lesion exhibited focal surface ulceration. A panoramic radiograph showed two implants at the vicinity of the lesion with no other significant findings. An excisional biopsy of the lesion followed by histopathologic examination of the biopsy specimen revealed salient and distinctive features of peripheral giant cell granuloma and of peripheral ossifying fibroma, estimated at near equal proportions. This raises the possibility of a hybrid odontogenic lesion.
  
  
  CONCLUSIONS
  The presentation of this lesion, with areas of peripheral giant cell granuloma along with a distinct area of extensive osseous formation and stroma reminiscent of a peripheral ossifying fibroma, justifies consideration of this as a possible hybrid lesion. Although the biologic behavior of a combined lesion is not anticipated to deviate significantly from that of either of the single entities, this case resurrects an enduring debate as to whether peripheral giant cell granuloma and peripheral ossifying fibroma are simply parts of a disease spectrum, or whether some of these lesions represent true hybrid lesions. It is therefore recommended that more cases with histopathologic features similar to the lesion in our case be reported in the literature to further elucidate the histogenesis of these lesions.
authors: Department of General Practice and Dental Public Health, The University of Texas School of Dentistry, Houston, TX, USA. Ezinne.I.Ogbureke@uth.tmc.edu.
authors: Ezinne I
authors: EI
authors: Ogbureke
authors: Department of Diagnostics and Biomedical Sciences, The University of Texas School of Dentistry, Houston, TX, USA. Nadarajah.Vigneswaran@uth.tmc.edu.
authors: Nadarajah
authors: N
authors: Vigneswaran
authors: Department of General Practice and Dental Public Health, The University of Texas School of Dentistry, Houston, TX, USA. Matthew.L.Seals@uth.tmc.edu.
authors: Matthew
authors: M
authors: Seals
authors: Department of General Practice and Dental Public Health, The University of Texas School of Dentistry, Houston, TX, USA. Gary.N.Frey@uth.tmc.edu.
authors: Gary
authors: G
authors: Frey
authors: Department of General Practice and Dental Public Health, The University of Texas School of Dentistry, Houston, TX, USA. Celerick.D.Johnson@uth.tmc.edu.
authors: Cleverick D
authors: CD
authors: Johnson
authors: Department of Diagnostics and Biomedical Sciences, The University of Texas School of Dentistry, Houston, TX, USA. Kalu.Ogbureke@uth.tmc.edu.
authors: Kalu U E
authors: KU
authors: Ogbureke
mesh_terms: D000328:Adult; D001706:Biopsy; D003937:Diagnosis, Differential; D018214:Fibroma, Ossifying / Q000150:complications* / Q000175:diagnosis*; D005881:Gingiva / Q000000981:diagnostic imaging / Q000473:pathology; D005887:Gingival Neoplasms / Q000150:complications* / Q000175:diagnosis*; D006101:Granuloma, Giant Cell / Q000150:complications* / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology; D008679:Metaplasia; D011859:Radiography
references: Oral Surg Oral Med Oral Pathol. 1953 Jan;6(1):159-75
references: 13026160
references: J Periodontol. 1990 Jul;61(7):444-6
references: 2117655
references: J Oral Implantol. 2016 Feb;42(1):55-60
references: 24059329
references: J Am Dent Assoc. 1966 Dec;73(6):1312-20
references: 5223950
references: Am J Dent Sci. 1848 Jul;8(4):313-350
references: 30750221
references: Histopathology. 1994 Nov;25(5):497-9
references: 7868092
references: Head Neck Pathol. 2008 Dec;2(4):333-8
references: 20614305
references: Oral Surg Oral Med Oral Pathol. 1987 Apr;63(4):452-61
references: 3472146
references: Int J Oral Maxillofac Surg. 1988 Apr;17(2):94-9
references: 3133432
references: J Oral Implantol. 2012 Sep;38 Spec No:527-32
references: 22712772
references: Histopathology. 1997 Feb;30(2):165-71
references: 9067742
references: Oral Surg Oral Med Oral Pathol. 1990 Oct;70(4):466-70
references: 2120653
references: J Int Acad Periodontol. 2004 Oct;6(4):131-5
references: 15553980
references: J Oral Maxillofac Surg. 1989 Jul;47(7):737-41
references: 2732834
references: Am J Dent Sci. 1843 Sep;4(1):53-54
references: 30749313
references: J Oral Sci. 2006 Dec;48(4):239-43
references: 17220623
references: Int J Oral Maxillofac Surg. 2010 May;39(5):503-7
references: 20005076
references: Oral Surg Oral Med Oral Pathol. 1992 Jan;73(1):62-6
references: 1603567