title: Bizarre parosteal osteochondromatous proliferation (Nora's Lesion) of the mandible. a rare bony lesion.
abstract: Bizarre parosteal osteochondromatous proliferation (BPOP) also eponymically called "Nora's lesion", is a rare benign reactive bone lesion first reported in 1983. BPOP occurs classically on the bones of the hands and feet and long bones. This lesion can easily be confused, both clinically and microscopically, with other benign and malignant lesions of bone, including osteochondroma, parosteal osteosarcoma, myositis ossificans and reactive periostitis. BPOP has been reported to have a high rate of recurrence. Only 3 cases of BPOP of the head and neck have been reported in the literature, of which one involved the maxilla. We present a rare case of BPOP involving the mandible in a 10 year old African American male. Microscopically, a fibro-cartilaginous cap giving rise to a proliferation of variably mineralized osteophytic finger-like projections of bone was seen. Multiple trabeculae of "blue bone" were noted as well as numerous atypical appearing chondrocytes. The lesion recurred within 4 months following the initial excision but has not recurred to date after the second local excision. To the best of our knowledge, this is the first report of BPOP arising in the mandible. In addition, we discuss the clinical and microscopic features, differential diagnosis, and prognosis of this rare entity. We present a case of BPOP of the mandible and believe this is the first report of such a case in the mandible.
authors.affiliation: Department of Oral & Maxillofacial Diagnostic Sciences, University of Florida College of Dentistry, 1600 Archer Road, P.O. Box: 100414, Gainesville, FL 32610, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Dashti
authors.forename: J D
authors.initials: JD
authors.lastname: Reith
authors.forename: B J
authors.initials: BJ
authors.lastname: Schlott
authors.forename: E L
authors.initials: EL
authors.lastname: Lewis
authors.forename: D M
authors.initials: DM
authors.lastname: Cohen
authors.forename: I
authors.initials: I
authors.lastname: Bhattacharyya
mesh_terms: D002648:Child; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology* / Q000601:surgery; D008339:Mandibular Neoplasms / Q000473:pathology* / Q000601:surgery; D009364:Neoplasm Recurrence, Local / Q000601:surgery; D015831:Osteochondroma / Q000473:pathology* / Q000601:surgery
references.citation: Am J Surg Pathol. 1993 Jul;17(7):691-7
references.pmid: 8317609
references.citation: Skeletal Radiol. 2001 May;30(5):282-5
references.pmid: 11407720
references.citation: Skeletal Radiol. 2001 Jan;30(1):44-7
references.pmid: 11289634
references.citation: Pathology. 1992 Jul;24(3):211-3
references.pmid: 1437297
references.citation: Hum Pathol. 2004 Sep;35(9):1063-9
references.pmid: 15343507
references.citation: Singapore Med J. 2003 Jan;44(1):27-30
references.pmid: 12762560
references.citation: Hum Pathol. 2002 Dec;33(12):1205-10
references.pmid: 12514790
references.citation: Skeletal Radiol. 2007 Jun;36(6):535-40
references.pmid: 17492328
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1999 Mar;87(3):351-6
references.pmid: 10102599
references.citation: Am J Surg Pathol. 2004 Aug;28(8):1033-9
references.pmid: 15252309
references.citation: Orthopedics. 1997 Dec;20(12):1186-8
references.pmid: 9415916
references.citation: Am J Surg Pathol. 1983 Apr;7(3):245-50
references.pmid: 6837834
references.citation: AJR Am J Roentgenol. 1987 Mar;148(3):650
references.pmid: 3492900
references.citation: Can J Surg. 2008 Dec;51(6):486-9
references.pmid: 19057740
references.citation: J Foot Ankle Surg. 2009 Nov-Dec;48(6):690.e7-690.e11
references.pmid: 19857830
references.citation: Skeletal Radiol. 2006 Jul;35(7):497-502
references.pmid: 16602017
references.citation: Pathol Int. 2001 Oct;51(10):816-23
references.pmid: 11881737
references.citation: Br J Oral Maxillofac Surg. 2011 Sep;49(6):e27-9
references.pmid: 20719415
references.citation: J Hand Surg Am. 2004 May;29(3):520-5
references.pmid: 15140499