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==Overview==
==Overview==
Osteoma (also known as ''Osteomata'') is a slow growing [[benign]] tumor of bone, occurring most commonly in the [[craniofacial]] skeletal structures, primarily in the nasal and paranasal (75-90%) cavities. Osteoma arises from bone overgrowth, which is normally composed of [[connective tissue]]. Osteomas are slow growing tumors composed of compact or mature [[trabecular bone]] limited to craniofacial bones. Osteoma may be incidentally identified as a mass in the [[skull]], [[mandible]], or as the underlying cause of [[sinusitis]] or [[mucocele]] formation within the [[paranasal sinuses]]. When they are multiple, Gardner syndrome should be considered. Osteoma represents the most common [[benign]] [[neoplasm]] of the [[nose]] and [[paranasal sinuses]]. The causes remain uncertain, but commonly accepted theories propose [[embryologic]], [[Trauma|traumatic]], or [[Infection|infectious]] causes. Osteomas are usually asymptomatic. [[Excision]] may be performed if osteoma is responsible for symptoms.
Osteoma (also known as ''Osteomata'') is a slow growing [[benign]] [[tumor]] of [[bone]], occurring most commonly in the [[craniofacial]] skeletal structures, primarily in the [[nasal]] and [[Paranasal sinus|paranasal]] (75-90%) sinuses. Osteoma arises from [[bone]] overgrowth, which is normally composed of [[connective tissue]]. Osteomas are slow growing [[tumors]] composed of compact or mature [[trabecular bone]] limited to [[craniofacial]] [[bones]]. Osteoma may be incidentally identified as a mass in the [[skull]], [[mandible]], or as the underlying cause of [[sinusitis]] or [[mucocele]] formation within the [[paranasal sinuses]]. When they are multiple, [[Gardner's syndrome|Gardner syndrome]] should be considered. Osteoma represents the most common [[benign]] [[neoplasm]] of the [[nose]] and [[paranasal sinuses]]. The causes remain uncertain, but commonly accepted theories propose [[embryologic]], [[Trauma|traumatic]], or [[Infection|infectious]] causes. Osteomas are usually [[asymptomatic]]. [[Excision]] may be performed if osteoma is responsible for [[symptoms]].


==Historical Perspective==
==Historical Perspective==


*In 1898, the description of [[craniofacial]] osteoma was first reported by Paul Schulze.<ref>{{cite book | last = Peabody | first = Terrance | title = Orthopaedic oncology : primary and metastatic tumors of the skeletal system | publisher = Springer | location = Cham | year = 2014 | isbn = 9783319073224 }}</ref>
*In 1898, the description of [[craniofacial]] osteoma was first reported by Paul Schulze.<ref>{{cite book | last = Peabody | first = Terrance | title = Orthopaedic oncology : primary and metastatic tumors of the skeletal system | publisher = Springer | location = Cham | year = 2014 | isbn = 9783319073224 }}</ref>
*In 1951, Eldon J. Gardner (1909–1989) a geneticist first described the occurrence of multiple osteomas in hereditary [[familial adenomatous polyposis]] (FAP).  
*In 1951, Eldon J. Gardner (1909–1989) a [[geneticist]] first described the occurrence of multiple osteomas in [[hereditary]] [[familial adenomatous polyposis]] (FAP).  
*In 2014, The Lancet published an article named "''Did René Descartes have a giant [[Ethmoid sinus|ethmoidal sinus]] osteoma?''" the authenticity has been confirmed by anthropological and historical investigations to be true.<ref name="pmid25307842">{{cite journal |vauthors=Charlier P, Froesch P, Benmoussa N, Froment A, Shorto R, Huynh-Charlier I |title=Did René Descartes have a giant ethmoidal sinus osteoma? |journal=Lancet |volume=384 |issue=9951 |pages=1348 |year=2014 |pmid=25307842 |doi=10.1016/S0140-6736(14)61816-X |url=}}</ref>
*In 2014, The Lancet published an article named "''Did René Descartes have a giant [[Ethmoid sinus|ethmoidal sinus]] osteoma?''" the authenticity has been confirmed by anthropological and historical investigations to be true.<ref name="pmid25307842">{{cite journal |vauthors=Charlier P, Froesch P, Benmoussa N, Froment A, Shorto R, Huynh-Charlier I |title=Did René Descartes have a giant ethmoidal sinus osteoma? |journal=Lancet |volume=384 |issue=9951 |pages=1348 |year=2014 |pmid=25307842 |doi=10.1016/S0140-6736(14)61816-X |url=}}</ref>


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===Enneking (MSTS) Staging System===
===Enneking (MSTS) Staging System===
*The Enneking surgical staging system (also known as the MSTS system) for benign [[Musculoskeletal system|musculoskeletal]] [[Tumor|tumors]] based on [[radiographic]] characteristics of the tumor host margin.<ref name="pmid20333492">{{cite journal| author=Jawad MU, Scully SP| title=In brief: classifications in brief: enneking classification: benign and malignant tumors of the musculoskeletal system. | journal=Clin Orthop Relat Res | year= 2010 | volume= 468 | issue= 7 | pages= 2000-2 | pmid=20333492 | doi=10.1007/s11999-010-1315-7 | pmc=2882012 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=20333492  }} </ref>
*The Enneking surgical staging system (also known as the MSTS system) for benign [[Musculoskeletal system|musculoskeletal]] [[Tumor|tumors]] based on [[radiographic]] characteristics of the [[tumor]] host margin.<ref name="pmid20333492">{{cite journal| author=Jawad MU, Scully SP| title=In brief: classifications in brief: enneking classification: benign and malignant tumors of the musculoskeletal system. | journal=Clin Orthop Relat Res | year= 2010 | volume= 468 | issue= 7 | pages= 2000-2 | pmid=20333492 | doi=10.1007/s11999-010-1315-7 | pmc=2882012 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=20333492  }} </ref>
*It is widely accepted and routinely used classification.
*It is widely accepted and routinely used classification.


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*The possibility of a reactive mechanism, triggered by trauma or infection, has been suggested.<ref name="pmid15111819">{{cite journal| author=Bilkay U, Erdem O, Ozek C, Helvaci E, Kilic K, Ertan Y et al.| title=Benign osteoma with Gardner syndrome: review of the literature and report of a case. | journal=J Craniofac Surg | year= 2004 | volume= 15 | issue= 3 | pages= 506-9 | pmid=15111819 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15111819  }} </ref>
*The possibility of a reactive mechanism, triggered by trauma or infection, has been suggested.<ref name="pmid15111819">{{cite journal| author=Bilkay U, Erdem O, Ozek C, Helvaci E, Kilic K, Ertan Y et al.| title=Benign osteoma with Gardner syndrome: review of the literature and report of a case. | journal=J Craniofac Surg | year= 2004 | volume= 15 | issue= 3 | pages= 506-9 | pmid=15111819 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15111819  }} </ref>
*Osteoma arises from bone overgrowth, which is normally composed of [[connective tissue]].<ref name="pmid25767729">{{cite journal |vauthors=Abdel Tawab HM, Kumar V R, Tabook SM |title=Osteoma presenting as a painless solitary mastoid swelling |journal=Case Rep Otolaryngol |volume=2015 |issue= |pages=590783 |year=2015 |pmid=25767729 |pmc=4341844 |doi=10.1155/2015/590783 |url=}}</ref>  
*Osteoma arises from bone overgrowth, which is normally composed of [[connective tissue]].<ref name="pmid25767729">{{cite journal |vauthors=Abdel Tawab HM, Kumar V R, Tabook SM |title=Osteoma presenting as a painless solitary mastoid swelling |journal=Case Rep Otolaryngol |volume=2015 |issue= |pages=590783 |year=2015 |pmid=25767729 |pmc=4341844 |doi=10.1155/2015/590783 |url=}}</ref>  
*Osteomas are slow growing tumors composed of compact or mature [[trabecular bone]] limited to craniofacial bones.
*Osteomas are slow growing [[tumors]] composed of compact or mature [[trabecular bone]] limited to craniofacial bones.
*Very rarely osteomas of the facial bones may be associated with Gardner's syndrome.   
*Very rarely osteomas of the facial bones may be associated with Gardner's syndrome.   
*Osteomas have a particular frequency distribution within the [[paranasal sinuses]]: frontal sinuses 80%, ethmoid air cells 15%, maxillary sinuses 5% and sphenoid sinus rare.
*Osteomas have a particular frequency distribution within the [[paranasal sinuses]]: frontal sinuses 80%, ethmoid air cells 15%, maxillary sinuses 5% and sphenoid sinus rare.

Latest revision as of 17:22, 3 April 2019


For patient information, click here
For more information about osteoid osteoma that is not associated with sino-orbital osteoma, see osteoid osteoma

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Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Osteoma from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Staging

History and Symptoms

Physical Examination

Laboratory Findings

X Ray

CT

MRI

Ultrasound

Other Imaging Findings

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Rohan A. Bhimani, M.B.B.S., D.N.B., M.Ch.[2]

Synonyms and keywords: Osteoma; Osteomata; Osteoncus; Ivory osteoma; Mature osteoma; Mixed osteoma; Homoplastic osteoma; Heteroplastic osteoma; Osteomas; Ivory exostosis; Sino-orbital osteoma; Sino-nasal osteoma; Paranasal sinus osteoma; Skull vault osteoma; Mandibular osteoma

Overview

Osteoma (also known as Osteomata) is a slow growing benign tumor of bone, occurring most commonly in the craniofacial skeletal structures, primarily in the nasal and paranasal (75-90%) sinuses. Osteoma arises from bone overgrowth, which is normally composed of connective tissue. Osteomas are slow growing tumors composed of compact or mature trabecular bone limited to craniofacial bones. Osteoma may be incidentally identified as a mass in the skull, mandible, or as the underlying cause of sinusitis or mucocele formation within the paranasal sinuses. When they are multiple, Gardner syndrome should be considered. Osteoma represents the most common benign neoplasm of the nose and paranasal sinuses. The causes remain uncertain, but commonly accepted theories propose embryologic, traumatic, or infectious causes. Osteomas are usually asymptomatic. Excision may be performed if osteoma is responsible for symptoms.

Historical Perspective

  • In 1898, the description of craniofacial osteoma was first reported by Paul Schulze.[1]
  • In 1951, Eldon J. Gardner (1909–1989) a geneticist first described the occurrence of multiple osteomas in hereditary familial adenomatous polyposis (FAP).
  • In 2014, The Lancet published an article named "Did René Descartes have a giant ethmoidal sinus osteoma?" the authenticity has been confirmed by anthropological and historical investigations to be true.[2]

Classification

Osteoma can be classified based on imaging findings.

Enneking (MSTS) Staging System

  • The Enneking surgical staging system (also known as the MSTS system) for benign musculoskeletal tumors based on radiographic characteristics of the tumor host margin.[3]
  • It is widely accepted and routinely used classification.
Stages Description
1 Latent: Well demarcated borders
2 Active: Indistinct borders
3 Aggressive: Indistinct borders

Pathophysiology

  • The exact etiology of osteoma is unknown.[4]
  • The possibility of a reactive mechanism, triggered by trauma or infection, has been suggested.[5]
  • Osteoma arises from bone overgrowth, which is normally composed of connective tissue.[6]
  • Osteomas are slow growing tumors composed of compact or mature trabecular bone limited to craniofacial bones.
  • Very rarely osteomas of the facial bones may be associated with Gardner's syndrome.
  • Osteomas have a particular frequency distribution within the paranasal sinuses: frontal sinuses 80%, ethmoid air cells 15%, maxillary sinuses 5% and sphenoid sinus rare.

Genetics

  • The hallmark of multiple osteomas is a mutation in the APC gene, that results in the Gardner syndrome.[7]

Causes

  • The cause of osteoma has not been identified.[8]

Differentiating ((Page name)) from Other Diseases

Osteoma must be differentiated from other diseases that cause sinus or facial pain, headache, and changes to or loss of sense of smell, such as other osteogenic tumors, fibrous dysplasia, and chronic sinusitis.[9][10]

Differential Diagnosis Similar Features Differentiating Features
Fibrous dysplasia
  • Benign, often an incidental finding, affects the same group of patients, and symptoms include facial pain and headache
  • In fibrous dysplasia, differentiating features include: More common presentation is on ribs: 28%, no gender predilection, and complete resection is usually not possible
Osteoblastoma
  • Benign, incidental, and male predilection
  • In osteoblastoma, differentiating features include: normally affect the axial skeleton, lesions are typically larger than 2 cm, and surgical excision is often the treatment of choice
Adamantinomas
  • Benign, slow growing, and similar clinical onset
  • In adamantinomas, differentiating features include: locally aggressive tumor, common in the 3rd to 5th decades of life, and location is usually confined to the jaw
Chronic sinusitis
  • Affects same group of population (young to middle aged adults) and the clinical presentation is similar
  • In chronic sinusitis, differentiating features include: fever, previous history of acute sinusitis, lack of facial deformation or imaging findings compatible with osteoma

Epidemiology and Demographics

  • The prevalence of osteoma is approximately 3000 per 100,000 individuals worldwide.[11]
  • The incidence of osteoma remains unknown.
  • Patients of all age groups may develop osteoma.
  • The average patient age varies from 25 to 35 years.
  • The mean age of the patients with osteoma is is 37 years.[9]
  • Men are more commonly affected than women, with a 3:1 ratio.[12]
  • There is no racial predilection to osteoma.

Risk Factors

There are no established risk factors for osteoma.[6]

Screening

Screening for multiple osteomas is recommended among patients with family history or/and a confirmed diagnosis of Gardner syndrome. Thyroid exam and annual ultrasound, should be performed starting at age 10 to 12 years.[13]

Natural History, Complications, and Prognosis

Diagnosis

Diagnostic Study of Choice

Biopsy is the diagnostic study of choice for the diagnosis of osteoma.

  • Gross appearance of osteoma include:
    • Osteomas have a spongy to densely appearance, conformed of in a polypoid and lobullated shape.[1]
    • The median size tumor size is 3.0 cm (range 0.5-8 cm).
    • Osteomas have a smooth surface and composed of dense compact bone (ivory osteoma), trabecular bone (mature osteoma, or both patterns).
Histology of osteoma.Source: Case courtesy of Nephron [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0) or GFDL (http://www.gnu.org/copyleft/fdl.html), from Wikimedia Commons]
  • Histological appearance includes:
    • Presence of dense compact mature bone in paucicellular fibrous stroma.
    • Large trabeculae of mature lamellar bone can be also be seen.

History and Symptoms

Physical Examination

X-ray showing osteoma of the frontal sinus.Source: Case courtesy of Dr Ahmed Abdrabou, Radiopaedia.org, rID: 42250
  • Patients with osteoid osteoma usually appears well.
  • Common physical examination findings of osteoid osteoma include:[18]

Laboratory Findings

There are no diagnostic laboratory findings associated with osteoma.

Electrocardiogram

There are no ECG findings associated with osteoma.

X-ray

  • Three views of affected bone or joint are recommended.[19]
  • Radiological findings for osteoma include:
    • Well circumscribed mass
    • Varying amounts of central lucency
    • Lobulated mass occupying frontal or maxillary sinus

Echocardiography or Ultrasound

CT showing osteoma of the mandible.Source: Case courtesy of Dr Ahmed Abdrabou, Radiopaedia.org, rID: 42250

There are no echocardiography/ultrasound findings associated with osteoma.

CT scan

  • CT findings of osteoma include:[20]
    • Well-circumscribed mass of variable density
    • Ground-glass appearance
    • Exophytical mass growing out of a sinus

MRI

  • MRI findings of osteoma include:[21]
    • Low signal on all sequences.
    • Mature osteomas may demonstrate some marrow signal, but are also predominantly low on all sequences

Other Imaging Findings

There are no other imaging findings associated with osteoma.

Other Diagnostic Studies

Nasal Endoscopy

Nasal endoscopy findings include:[22]

  • Direct visualization of the nasal passages structures, and sinuses.
  • Tumor location, size, and adjacent structure evaluation.

Treatment

Medical Therapy

There is no medical treatment for osteoma; the mainstay of therapy is surgery.[23]

Surgery

Surgery is the mainstay of treatment for osteoma.[24][25]

Indication

  • For symptomatic lesions, local excision is performed.

Types of Surgery

Recurrence Rare recurrence may occur after several years.

Primary Prevention

There are no established measures for the primary prevention of osteoma.

Secondary Prevention

There are no established measures for the secondary prevention of osteoma.

References

  1. Peabody, Terrance (2014). Orthopaedic oncology : primary and metastatic tumors of the skeletal system. Cham: Springer. ISBN 9783319073224.
  2. Charlier P, Froesch P, Benmoussa N, Froment A, Shorto R, Huynh-Charlier I (2014). "Did René Descartes have a giant ethmoidal sinus osteoma?". Lancet. 384 (9951): 1348. doi:10.1016/S0140-6736(14)61816-X. PMID 25307842.
  3. Jawad MU, Scully SP (2010). "In brief: classifications in brief: enneking classification: benign and malignant tumors of the musculoskeletal system". Clin Orthop Relat Res. 468 (7): 2000–2. doi:10.1007/s11999-010-1315-7. PMC 2882012. PMID 20333492.
  4. Athwal P, Stock H (2014). "Osteoid osteoma: a pictorial review". Conn Med. 78 (4): 233–5. PMID 24830123.
  5. Bilkay U, Erdem O, Ozek C, Helvaci E, Kilic K, Ertan Y; et al. (2004). "Benign osteoma with Gardner syndrome: review of the literature and report of a case". J Craniofac Surg. 15 (3): 506–9. PMID 15111819.
  6. 6.0 6.1 Abdel Tawab HM, Kumar V R, Tabook SM (2015). "Osteoma presenting as a painless solitary mastoid swelling". Case Rep Otolaryngol. 2015: 590783. doi:10.1155/2015/590783. PMC 4341844. PMID 25767729. Vancouver style error: name (help)
  7. Bisgaard ML, Bülow S (2006). "Familial adenomatous polyposis (FAP): genotype correlation to FAP phenotype with osteomas and sebaceous cysts". Am J Med Genet A. 140 (3): 200–4. doi:10.1002/ajmg.a.31010. PMID 16411234.
  8. Kaplan I, Calderon S, Buchner A (1994). "Peripheral osteoma of the mandible: a study of 10 new cases and analysis of the literature". J Oral Maxillofac Surg. 52 (5): 467–70. PMID 8169708.
  9. 9.0 9.1 Erdogan N, Demir U, Songu M, Ozenler NK, Uluç E, Dirim B (2009). "A prospective study of paranasal sinus osteomas in 1,889 cases: changing patterns of localization". Laryngoscope. 119 (12): 2355–9. doi:10.1002/lary.20646. PMID 19780030.
  10. Larrea-Oyarbide N, Valmaseda-Castellón E, Berini-Aytés L, Gay-Escoda C (2008). "Osteomas of the craniofacial region. Review of 106 cases". J Oral Pathol Med. 37 (1): 38–42. doi:10.1111/j.1600-0714.2007.00590.x. PMID 18154576.
  11. Earwaker J (1993). "Paranasal sinus osteomas: a review of 46 cases". Skeletal Radiol. 22 (6): 417–23. PMID 8248815.
  12. Boysen M (1978). "Osteomas of the paranasal sinuses". J Otolaryngol. 7 (4): 366–70. PMID 691104.
  13. Septer S, Slowik V, Morgan R, Dai H, Attard T (2013). "Thyroid cancer complicating familial adenomatous polyposis: mutation spectrum of at-risk individuals". Hered Cancer Clin Pract. 11 (1): 13. doi:10.1186/1897-4287-11-13. PMC 3854022. PMID 24093640.
  14. Sayan NB, Uçok C, Karasu HA, Günhan O (2002). "Peripheral osteoma of the oral and maxillofacial region: a study of 35 new cases". J Oral Maxillofac Surg. 60 (11): 1299–301. PMID 12420263.
  15. 15.0 15.1 Wijn MA, Keller JJ, Giardiello FM, Brand HS (2007). "Oral and maxillofacial manifestations of familial adenomatous polyposis". Oral Dis. 13 (4): 360–5. doi:10.1111/j.1601-0825.2006.01293.x. PMID 17577321.
  16. GARDNER EJ, PLENK HP (1952). "Hereditary pattern for multiple osteomas in a family group". Am. J. Hum. Genet. 4 (1): 31–6. PMC 1716387. PMID 14933371.
  17. Smith ME, Calcaterra TC (1989). "Frontal sinus osteoma". Ann Otol Rhinol Laryngol. 98 (11): 896–900. doi:10.1177/000348948909801111. PMID 2817682.
  18. Fu YS, Perzin KH (1974). "Non-epithelial tumors of the nasal cavity, paranasal sinuses, and nasopharynx. A clinicopathologic study. II. Osseous and fibro-osseous lesions, including osteoma, fibrous dysplasia, ossifying fibroma, osteoblastoma, giant cell tumor, and osteosarcoma". Cancer. 33 (5): 1289–305. PMID 4207295.
  19. Schajowicz, Fritz (1994). Tumors and Tumorlike Lesions of Bone : Pathology, Radiology, and Treatment. Berlin, Heidelberg: Springer Berlin Heidelberg. ISBN 9783642499562.
  20. Schajowicz, Fritz (1994). Tumors and Tumorlike Lesions of Bone : Pathology, Radiology, and Treatment. Berlin, Heidelberg: Springer Berlin Heidelberg. ISBN 9783642499562.
  21. Schajowicz, Fritz (1994). Tumors and Tumorlike Lesions of Bone : Pathology, Radiology, and Treatment. Berlin, Heidelberg: Springer Berlin Heidelberg. ISBN 9783642499562.
  22. Li Y, Zhang L, Zhou B, Han D (2009). "[Resection of frontal ethmoid sinus osteomas with nasal endoscopy]". Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi (in Chinese). 23 (14): 628–30. PMID 19894552.
  23. Gorini E, Mullace M, Migliorini L, Mevio E (2014). "Osseous choristoma of the tongue: a review of etiopathogenesis". Case Rep Otolaryngol. 2014: 373104. doi:10.1155/2014/373104. PMC 4279709. PMID 25580337.
  24. Kim WH, Kim DW, Kim CG, Kim MH (2013). "Additional Detection of Multiple Osteomas in a Patient with Gardner's Syndrome by Bone SPECT/CT". Nucl Med Mol Imaging. 47 (4): 297–8. doi:10.1007/s13139-013-0225-5. PMC 4035179. PMID 24900131.
  25. Alexander AA, Patel AA, Odland R (2007). "Paranasal sinus osteomas and Gardner's syndrome". Ann Otol Rhinol Laryngol. 116 (9): 658–62. doi:10.1177/000348940711600906. PMID 17926587.


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