International Journal of Oral & Maxillofacial Pathology. 2012;3(3):26-30 ISSN 2231 – 2250

Available online at http://www.journalgateway.com or www.ijomp.org

Case Report

Intraosseous Lipoma of the Mandible: A Case Report and Review of the Literature

Nevin Büyükakyüz, Sertan Ergun, Murat Öztürk, Vakur Olgac

Abstract

Lipoma is a benign tumor which consists of mature adipose tissue and represents the most commonly diagnosed mesenchymal neoplasm. It is the most common form of soft tissue tumor where as intraosseous lipomas are uncommon and are considered among the rarest benign primary tumors of bone. There are only few documented cases of central lipomas in the jaws. This report describes a rare case of mandibular intraosseous lipoma in the incisor area in a 48- year-old female patient and summarizes the related literature. In conclusion intraosseous lipoma should be considered in the differential diagnosis of other intraosseous lesions. The characteristic finding of this lesion is the presence of mature adipose fat cells and histologic examination is mandatory for the diagnosis.
Keywords: Intraosseous;Lipoma;Benign;Neoplasms;Adipose Tissue;Bone Tumor;Mandible.

Nevin Büyükakyüz, Sertan Ergun, Murat Öztürk, Vakur Olgac. Intraosseous Lipoma of the Mandible: A Case

Report and Review of the Literature. International Journal of Oral & Maxillofacial Pathology; 2012:3(3):26-30.

©International Journal of Oral and Maxillofacial Pathology. Published by Publishing Division, Celesta

Software Private Limited. All Rights Reserved.

Received on: 05/06/2011 Accepted on: 09/09/2012

Introduction

Lipomas are benign tumors of mature adipose tissue with no evidence of cellular atypia.1.2 They are usually solitary, soft and sessile to polypoid and are composed of
mature adipose cells, occasionally with foci of myxoid stroma.2 Lipomas occur more frequently between the fifth and the seventh
decades of the life and have no gender or race predilection.3 Although lipomas are very common, intraosseous lipoma is a very rare tumor. It is classified as a benign soft tissue
tumour (ICD-O code 8850/0) in the WHO
histological classification of tumors of the oral cavity, hypopharynx, larynx and trachea.4 According to the literatures the incidence of intraosseous lipoma is less than
0.1% of all intrabony tumors. Intraosseous
lipomas generally present in the metaphysis of the long bones and the calcaneus.3,5-7 The demographical, radiological and clinical features of the reported cases3,5,7-22 of intraosseous lipomas of the jaws have been described in Table 1. We report a rare case of an intraosseous mandibular lipoma which
was incidentally discovered on the routine radiographic examination.

Case Report

A 48 year old female patient was referred by her dentist to the department of oral surgery for evaluation of a radiolucency in the incisor area of the mandible. Orthopantographic examination revealed a bone impacted left upper wisdom tooth, small apical lesions
related to the first right both upper and lower molars. There was an asymptomatic radiolucent area which was located between the mandibular canines and below the apices of mandibular incisors, measuring 3 x
2 cm in its largest diameter with sclerotic margins (Figure 1). No external root resorption was observed. Extraoral and intraoral examination was noncontributory. Pulp vitality tests for the mandibular incisor teeth were positive. There was no history of any systemic disease or trauma in the maxillofacial region. The patient was asked for a computed tomography examination but the patient was afraid of getting an extra X- Ray and refused the computed tomography examination.
A provisional clinical diagnosis of odontogenic cyst was raised and enucleation of the radiolucent lesion under local anesthesia was suggested to the patient. After obtaining informed consent from the patient, under mandibular and infiltration anesthesia bilaterally, the muccoperiostal flap was raised and the cortical bone was exposed. The lesion was reached, exposed and enucleated, totally. After primary closure of the surgical site, antibiotics (Amoxicillin 1g, twice a day, orally), non-steroid anti inflammatory drugs (Naproxen sodium 550 mg, twice a day, orally) and oral rinse (Chlorhexidine- Gluconate 30 ml, three times daily) were prescribed. The specimens of the lesion

©2012 International Journal of Oral and Maxillofacial Pathology. Published by Publishing Division, Celesta Software Private Limited . All Rights Reserved

ISSN 2231 – 2250 Intraosseous Lipoma of the Mandible: A Case..... 27


were placed in 10% buffered formalin fixative and processed routinely for light microscopy. Histopathological examination revealed that the lesion was composed of mature adipose tissue and some connective tissue (Figure 2). The definitive final diagnosis of intraosseous lipoma was arrived at. The postoperative healing period was uneventful. In the follow-up period we could not take a control radiograph because the patient refused to submit herself to adjunctive radiographic examination wherefore her fear of getting an extra X-Ray.

Fig. 1. The radiolucent area with sclerotic margins in the symphyseal region of the mandible.
Fig.2. The lesion consists of mature adipose tissue with some bone islands and a calcification area (H & E, magnification X400).

Discussion

Soft tissue lipoma is a common, benign tumour of adipose tissue that may affect any part of the body. However, although adults have large amount of fatty marrow, intraosseous lipoma is one of the rarest benign tumor of the bone and comprises approximately 0.1% of all bone tumors. These cases usually have been reported in the long bones and calcaneus and rarely in
maxillofacial region.20 Two retrospective studies have analyzed 125 and 58 cases of
lipomas respectively, located in the oral and maxillofacial region, and found that no case of lipoma was found in the jaw bones.1,23
Literature search revealed that intraosseous lipomas in maxillofacial region are mostly located in the posterior part of the mandible (61.11%), followed by the anterior part of the mandible (22.22%). In our case the lesion was located in the symphyseal mandibular area which was compatible with the literature. Although definitive diagnosis of an intraosseous lesion is possible only by histopathological examination, computed tomography and magnetic resonance imaging findings of intraosseous lipoma are typical. In most patients symptoms are relieved by conservative means. Even if intraosseous lipoma is an uncommon bone tumor, physicians should be familiar with the radiological features of this lesion for the
correct diagnosis.24 In the present case, the lesion appeared in panoramic radiography as a well defined, unilocular radiolucent image with sclerotic margins.
The etiology of intraosseous lipoma is unknown, intraosseous lipomas might be asymptomatic and are found incidentally in radiographic examinations.7 The most
frequent symptoms of the intraosseous
lipoma in the jaws are paresthesia and external root resorption, both were absent in our case because of the unique location. Most of the previous references stressed that the treatment protocol of the intraosseous lipoma is surgical intervention by curretage or local resection whereas Bagatur et al., suggest only clinical and radiological follow-up of the intraosseous lipoma is sufficient as computed tomography and magnetic resonance imaging findings of intraosseous lipoma are typical and if there is no risk of pathologic fracture or
suspicion of malignancy.24 No reccurence or any malignant changes of intraosseous
lipomas in maxillofacial region have been reported.3,5,7,20
Milgram classified intraosseous lipomas into three stages according to their radiological and histological features17,25 In stage 1, the lesion contains just adipose tissue without
any necrosis, cyst or trabecular resorption.
In stage 2, there may be occasional adipose tissue, necrosis and regional dystrophic calcifications. In stage 3, there are involutional changes such as advanced level of adipose tissue necrosis, cyst formation, calcification, and reactive new bone formation. Our case could be classified as intraosseous lipoma in stage 1 because of the absence of any cyst, reactive bone formation and extensive fatty necrosis.

28 Nevin Büyükakyüz et al. ISSN 2231 - 2250

Intraosseous mandibular lipomas which were reported previously were commonly
consistent with stage I lesions such as present case.

Authors

Age

Sex

Localization

Clinical Features

Histopatholigical

Diagnosis

Radiographic

Features

Oringer

(1948)

37

F

Posterior part of the mandibula

Increasing pain during chewing

and pressure in

molar region

Intraosseous

Lipoma

Radiolucency

Newman

(1957)

65

M

Posterior part of the mandibula

Asymptomatic

Fibrolipoma

Radiolucency

Johnson

(1969)

21

M

Cyst around mandibular right

second and third

molars

Bad taste, pain, and swelling

Intraosseous

Lipoma

Radiolucency

Polte et al (1976)

39

M

Body

of mandible

Hypoesthesia of the chin region

Angiolipoma

Radiolucency

Steiner et al (1981)

50

M

Posterior crestal bone and

anterior ramus

Asymptomatic

Parosteolipoma

Radiolucency

Lewis et al (1980)

56

F

Mandibular body with mild

hypoesthesia

Asymptomatic

Angiolipoma

Radiolucency

Miller et al (1982)

51

M

Impacted left mandibular third

molar pathology

Asymptomatic +

İmpacted third

molar

Intraosseous

Lipoma

Radiolucency

Heir and

Geron

(1983)

43

F

Left anterior ramus

Trigeminal neuropathy

Intraosseous

Lipoma

Radiolucency

Barker

and Sloan (1986)

53

F

Retained root

apex of third mandibular molar

Symptomless retained roots

Intraosseous

Lipoma

Radiolucency

Mangana ro et al (1994)

51

M

Mandibular ramus

Symptomless ramus thinning

Angiolipoma

Radiolucency / Radiopaque

Koami et al (1995)

59

M

Symphyseal mandibular

gingiva

Symptomless swelling

Intraosseous

Lipoma

Radiolucency

Sakashit a et al

(1998)

17

M

Left Side of

Maxilla

Asymptomatic

Intraosseous

Lipoma

Radiolucency

Buric et al (2001)

62

F

Symphyseal and paramental

region under

retained roots

Symptomless swelling

Intraosseous

Lipoma

Radiolucency

Keogh et al (2004)

56

F

Posterior part of the mandibula

Symptomless swelling

Intraosseous

Lipoma

Radiolucency

Cakarer et al

(2009)

45

F

Anterior part of the mandibula

Asymptomatic

Intraosseous

Lipoma

Radiolucency

Gonzales

-Perez et al (2010)

61

F

Left mandibular ramus

Swelling in the left preauricular

region

Intraosseous

Lipoma

Radiolucency

Morais et al (2011)

39

F

Posterior part of the maxilla

Discomfort in the region of tooth

#28

Intraosseous

Lipoma

No radiographic

examination

preoperatively

Table 1. The demographical, radiological and clinical features of the reported cases of
intraosseous lipomas of the jaws.
We previosly reported that the majority of the dentists working in Istanbul preferred to consult with specialists in the departments of
dermatology and internal medicine, as opposed to oral medicine or surgery.26 In the present case, the patient’s dentists had

ISSN 2231 – 2250 Intraosseous Lipoma of the Mandible: A Case..... 29

referred the patient to our department for evaluation of the radiolucency in the mandible which he noticed in the routine radiological examination although the patient had no symptoms related to the lesion.
In conclusion, intraosseous lipomas in the jaws are uncommon and are difficult to diagnose. There are few reported cases in the literature of the appearence of intraosseous lipoma in the jaw bones. The influence of the clinical characteristics of this lesion to the decision-making process are not significant. Therefore a histopathological examination is the gold standard for the differential diagnosis. The characteristic finding is the presence of mature adipose fat cells. Complete surgical removal is the treatment choice for intraosseous lipoma with no previously reported recurrence.

Author Affiliations

1. Dr.Nevin Büyükakyüz, 2. Dr.Sertan Ergun, Associate Professor, 3. Dr.Murat Öztürk, Faculty of Dentistry, Department of Oral Surgery, 4. Dr.Vakur Olgac, Istanbul University, Institute of Oncology, Department of Tumor Pathology and Oncology Cytology, Istanbul, Turkey.

Acknowledgement

We would like to thank all the staff members from Department of Oral Pathology and Oral Surgery for their support & cooperation.

References

1. Furlong MA, Fanburg-Smith JC, Childers LB. Lipoma of the oral and maxillofacial region: Site and subclassification of 125 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2004;98(4):441-50.
2. Stokes SM, Wood JP, Castle JT.
Maxillary intraosseous spindle cell lipoma. J Oral Maxillofac Surg
2011;69(6):e131-4.
3. González-Pérez LM, Pérez-Ceballos JL, Carranza-Carranza A. Mandibular intraosseous lipoma: clinical features of a condylar location. Int J Oral Maxillofac Surg 2010;39(6):617-20.
4. Barnes L, Eveson JW, Reichart P, Sidransky D. Pathology and Genetics, Head and Neck Tumours. World Health Organization Classification of Tumours, WHO Publications Center Albany: 2007; p108.
5. Morais AL, Mendonça EF, de Alencar AH, Estrela C. Intraosseous lipoma in the periapical region of a maxillary third molar. J Endod 2011;37(4):554-7.
6. Sakashita H, Miyata M, Okabe K.
Intraosseous lipoma of the maxilla. A
case report. Int J Oral Maxillofac Surg
1998;27(1):63-4.
7. Cakarer S, Selvi F, Isler SC, Soluk M, Olgac V, Keskin C. Intraosseous lipoma of the mandible: A case report and review of the literature. Int J Oral and Maxillofac Surg 2009;38(8):900-2.
8. Oringer MJ. Lipoma of the mandible. Oral Surg Oral Med Oral Pathol 1948;1(12):1134.
9. Newman CW. Fibrolipoma of the mandible: Report of case. J Oral Surg
1957;15(3):251-2.
10. Johnson EC. Intraosseous lipoma: Report of case. J Oral Surg
1969;27(11):868-70.
11. Polte HW, Kolodny SC, Hooker SP.
Intraosseous angiolipoma of the mandible. Oral Surg Oral Med Oral Pathol 1976;41(5):637-43.
12. Steiner M, Gould A, Rasmussen J, LaBriola D. Parosteal lipoma of the mandible. Oral Surg Oral Med Oral Pathol 1981;52(1):61-5.
13. Lewis DM, Brannon RB, Isaksson B, Larsson A. Intraosseous angiolipoma of the mandible. Oral Surg Oral Med Oral Pathol 1980;50(2):156-9.
14. Miller WB, Ausich JE, McDaniel RK, Longo JJ. Mandibular intraosseous lipoma. J Oral Maxillofac Surg
1982;40(9):594-6.
15. Heir GM, Geron PR. Mandibular intraosseous lipoma related to trigeminal neuropathy. Clin Prevent Dent
1983;5(1):13-5.
16. Barker GR, Sloan P. Intraosseous lipomas: Clinical features of a mandibular case with possible aetiology. Br J Oral Maxillofac Surg
1986;24(6):459-63.
17. Milgram JW. Intraosseous lipomas: radiologic and pathologic manifestations. Radiol 1988;167(1):155-60.
18. Manganaro AM, Hammond HL, Williams TP. Intraosseous angiolipoma of the mandible: A case report and review of literature. J Oral Maxillofac Surg
1994;52(7):767-9.
19. Koami T, Nishijima Y, Nishijima K. A case of intraosseous lipoma in the mandible. Jpn J Oral Maxillofac Surg
1995;41:875-7.
20. Sakashita H, Miyata M, Okabe K.
Intraosseous lipoma of the maxilla. A
case report. Int J Oral Maxillofac Surg
1998;27(1):63-4.
21. Burić N, Krasić D, Visnjić M, Katić V.
Intraosseous mandibular lipoma: a case

30 Nevin Büyükakyüz et al. ISSN 2231 - 2250

report and review of the literature. J Oral
Maxillofac Surg 2001;59(11):1367-71.
22. Keogh PV, McDonnell D, Toner M.
Intraosseous mandibular lipoma (IML): a case report and review of the literature. J Ir Dent Assoc 2004;50(3):132-4.
23. Manor E, Sion-Vardy N, Joshua BZ, Bodner L. Oral lipoma: analysis of 58 new cases and review of the literature.
Ann Diagn Pathol 2011;15(4):257-61.
24. Bagatur AE, Yalcinkaya M, Dogan A, Gur S, Mumcuoglu E, Albayrak M. Surgery is not always necessary in intraosseous lipoma. Orthopedics
2010;12(5):33.
25. Milgram JW. Intraosseous lipomas: a clinicopathologic study of 66 cases. Clin Orthop 1988;231:277-302.
26. Ergun S, Ozel S, Koray M, Kürklü E, Ak G, Tanyeri H. Dentists' knowledge and opinions about oral mucosal lesions. Int J Oral Maxillofac Surg 2009;38:1283-8.

Corresponding Author Dr. Sertan Ergun, Associate Professor,

Istanbul University, Faculty of Dentistry, Department of Oral Surgery,

Istanbul, Turkey.

Email: sertanergun@gmail.com

Source of Support: Nil, Conflict of Interest: None Declared.


Fatal error: Call to a member function getRouter() on null in /home/journalg/public_html/lib/pkp/classes/template/PKPTemplateManager.inc.php on line 71