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Intraosseous lipoma of the maxilla
Int. J. Oral Maxillofac. Surg. 1998; 27:6344 Printed in Denmark. All rights reserved
Copyright 9 Munksgaard 1998 InternationalJournalof
Oral& MaxillofacialSurgery ISSN 0901-5027
Intraosseous lipoma of the maxilla
Hideaki Sakashita, Masaru Miyata, Koichi Okabe Department of Dentistry and Oral Surgery, Ishikawa Central Hospital, Ishikawa, Japan
A case report H. Sakashita, M. Miyata, K. Okabe: Intraosseous lipoma o f the maxilla. A case report. Int. J. Oral Maxillofac. Surg. 1998; 27: 63-64. 9 Munksgaard, 1998 Key words: intraosseous tipoma; maxilla.
Abstract. A case of intraosseous lipoma occurring in the maxilla of a 17-year-old boy is described.
Accepted for publication30 July 1997
L i p o m a is a benign tumour consisting of mature adipose tissue with no evid e n c e of cellular atypia. A l t h o u g h lipomas occur mainly in subcutaneous tissues, they may develop in any site of the body where adipose tissue is present. Adipose tissue occurs in bone marrow and so the development of intraosseous lipoma (IOL) should be expected. IOL, however, is rare. It usually presents in adults and most often involves the long bones and calcaneus 6. Only a few cases o f I O L arising in the jaws have been reported 2,s, so the present case appears to be of interest.
ation showed a well defined unilocular radiolucency (Fig. 1B) with intact buccal and palatal cortex. On this evidence, primordial cyst was the most obvious differential diagnosis. The treatment was undertaken with the patient under general anesthesia. The deciduous molar was extracted. After reflection of a mucoperiosteal flap, the overlying bone was removed, and the lesion was exposed and enucleated. There was no evidence of any cystic cavity and lining. Macroscopically, the lesion was yellow and soft, and appeared to be surrounded by a thin connective tissue layer. Routine histological examination revealed that the lesion was composed of mature, adipose tissue and some connective tissue (Fig. 2). A diagnosis
Case report A 17-year-old Japanese boy was referred to our department for evaluation of a radiolucency in the left side of the maxilla. His dentist had found an asymptomatic, radiolucent area adjacent to the apex of the retained left maxillary 2nd deciduous molar (Fig. 1A). Intraoral examination revealed no abnormal findings. The patient's left maxillary permanent 2nd premolar was missing, whereas the deciduous molar appeared to be in good condition and responded to electrical pulp testing. The patient did not recall that he had had the premolar extracted, which was, therefore, presumed to be congenitally missing. A computed tomographic examin-
Fig. 1A. Periapical radiograph shows well defined radiolucency. Fig. lB. CT scan shows expanding nature of lesion. Note intact maxillary cortex.
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volving the maxillary tuberosity could be thus explained8, but the expanding nature of the tumour in the present case does not support this hypothesis. The relationship between the IOL and missing premolar in the present case is not obvious.
References
1. HARTJAL. lntraosseous lipoma. J Bone Joint Surg 1973: 55B: 624-32. 2. KOAMI T, NISHIJIMA Y, NISHIJIMA K. A
Fig. 2. Light photomicrograph shows that the lesion consisted of mature adipose tissue. A 'capsule' of fibrovascular connective tissue is present (HE• 100).
case of intraosseous lipoma in the mandible. Jpn J Oral Maxillofac Surg 1995: 41:875 7. 3. MILGRAMJW. Intraosseous lipomas: radiologic and pathologic manifestations. Radiology 1988: 167: 155-60. 4. MmanAu JW. Malignant transformation in bone lipomas. Skeletal Radiol 1990: 19: 34~52. 5. MIYAMOTOH, SAKASHITAH, NAKAGAWA K. LIPOSARCOMA:report of a case and re-
of simple lipoma was made. The postoperative course was uneventful. Discussion
The clinical, radio-logical and histological features of the present case can be reconciled within the range of IOL of the maxilla. A search of the literature revealed that only five cases of maxillary IOL v,s have. been previously reported. IOL of the jaws usually occurs in adults s, so the patient described in this report is the youngest to date, The symptoms of IOL of the jaws vary, depending upon the location and size of the tumour. If the tumour is not treated and growth is extensive, paresthesia and external root resorption may occur 1,2. In the present case, there were no symptoms, and the only evidence suggesting a tumour was a radiolucent area with retained deciduous teeth.
Clinically, it is necessary to differentiate odontogenic cysts and benign, solid lesions from IOL occurring in the jaws, whereas histologically the differential diagnosis should include a focal osteoporotic bone marrow defect of the jaws and intraosseous well differentiated liposarcoma. These were excluded in the present case on the basis of lack of red marrow elements and adipocytic atypia respectively. Four cases of malignant transformation of IOL have been reported 4, but to our knowledge no case of malignant transformation of IOL arising in the jaws has been described. Although it has been proposed that IOL may arise from adipose tissue of bone marrow, the origin and cause of IOL are uncertain1-3'6. An intriguing possibility that should be considered, however, is that IOL might correspond to osteoporotic bone marrow defects containing yellow marrow. Cases of IOL in-
view of the literature. Jpn J Oral Maxillofac Surg 1982: 28:1149 59. 6. SCHAJOWICZ E Histological typing of bone tumours. 2nd ed. Berlin: SpringerVerlag, 1993: 30. 7. SALZER M, SALZER-KUNTSCHIKM. Zur
Frage der sogenannten zentralen Knochenlipoma. Beitr Path Anat 1965: 132: 365-75. 8. To WH, YELrN~KH. Intraosseous lipoma of maxillary tuberosity. Br J Oral Maxillofac Surg 1991: 30: 122-4.
Address: Dr Hideaki Sakashita, DDS, PhD Department of Dentistry and Oral Surgery Ishikawa PreJectural Central Hospital Nu-153, Minamishinbo-machi Kanazawa, Ishikawa 920 Japan
Copyright 9 Munksgaard 1998 InternationalJournalof
Oral& MaxillofacialSurgery ISSN 0901-5027
Intraosseous lipoma of the maxilla
Hideaki Sakashita, Masaru Miyata, Koichi Okabe Department of Dentistry and Oral Surgery, Ishikawa Central Hospital, Ishikawa, Japan
A case report H. Sakashita, M. Miyata, K. Okabe: Intraosseous lipoma o f the maxilla. A case report. Int. J. Oral Maxillofac. Surg. 1998; 27: 63-64. 9 Munksgaard, 1998 Key words: intraosseous tipoma; maxilla.
Abstract. A case of intraosseous lipoma occurring in the maxilla of a 17-year-old boy is described.
Accepted for publication30 July 1997
L i p o m a is a benign tumour consisting of mature adipose tissue with no evid e n c e of cellular atypia. A l t h o u g h lipomas occur mainly in subcutaneous tissues, they may develop in any site of the body where adipose tissue is present. Adipose tissue occurs in bone marrow and so the development of intraosseous lipoma (IOL) should be expected. IOL, however, is rare. It usually presents in adults and most often involves the long bones and calcaneus 6. Only a few cases o f I O L arising in the jaws have been reported 2,s, so the present case appears to be of interest.
ation showed a well defined unilocular radiolucency (Fig. 1B) with intact buccal and palatal cortex. On this evidence, primordial cyst was the most obvious differential diagnosis. The treatment was undertaken with the patient under general anesthesia. The deciduous molar was extracted. After reflection of a mucoperiosteal flap, the overlying bone was removed, and the lesion was exposed and enucleated. There was no evidence of any cystic cavity and lining. Macroscopically, the lesion was yellow and soft, and appeared to be surrounded by a thin connective tissue layer. Routine histological examination revealed that the lesion was composed of mature, adipose tissue and some connective tissue (Fig. 2). A diagnosis
Case report A 17-year-old Japanese boy was referred to our department for evaluation of a radiolucency in the left side of the maxilla. His dentist had found an asymptomatic, radiolucent area adjacent to the apex of the retained left maxillary 2nd deciduous molar (Fig. 1A). Intraoral examination revealed no abnormal findings. The patient's left maxillary permanent 2nd premolar was missing, whereas the deciduous molar appeared to be in good condition and responded to electrical pulp testing. The patient did not recall that he had had the premolar extracted, which was, therefore, presumed to be congenitally missing. A computed tomographic examin-
Fig. 1A. Periapical radiograph shows well defined radiolucency. Fig. lB. CT scan shows expanding nature of lesion. Note intact maxillary cortex.
64
Sakashita et al.
volving the maxillary tuberosity could be thus explained8, but the expanding nature of the tumour in the present case does not support this hypothesis. The relationship between the IOL and missing premolar in the present case is not obvious.
References
1. HARTJAL. lntraosseous lipoma. J Bone Joint Surg 1973: 55B: 624-32. 2. KOAMI T, NISHIJIMA Y, NISHIJIMA K. A
Fig. 2. Light photomicrograph shows that the lesion consisted of mature adipose tissue. A 'capsule' of fibrovascular connective tissue is present (HE• 100).
case of intraosseous lipoma in the mandible. Jpn J Oral Maxillofac Surg 1995: 41:875 7. 3. MILGRAMJW. Intraosseous lipomas: radiologic and pathologic manifestations. Radiology 1988: 167: 155-60. 4. MmanAu JW. Malignant transformation in bone lipomas. Skeletal Radiol 1990: 19: 34~52. 5. MIYAMOTOH, SAKASHITAH, NAKAGAWA K. LIPOSARCOMA:report of a case and re-
of simple lipoma was made. The postoperative course was uneventful. Discussion
The clinical, radio-logical and histological features of the present case can be reconciled within the range of IOL of the maxilla. A search of the literature revealed that only five cases of maxillary IOL v,s have. been previously reported. IOL of the jaws usually occurs in adults s, so the patient described in this report is the youngest to date, The symptoms of IOL of the jaws vary, depending upon the location and size of the tumour. If the tumour is not treated and growth is extensive, paresthesia and external root resorption may occur 1,2. In the present case, there were no symptoms, and the only evidence suggesting a tumour was a radiolucent area with retained deciduous teeth.
Clinically, it is necessary to differentiate odontogenic cysts and benign, solid lesions from IOL occurring in the jaws, whereas histologically the differential diagnosis should include a focal osteoporotic bone marrow defect of the jaws and intraosseous well differentiated liposarcoma. These were excluded in the present case on the basis of lack of red marrow elements and adipocytic atypia respectively. Four cases of malignant transformation of IOL have been reported 4, but to our knowledge no case of malignant transformation of IOL arising in the jaws has been described. Although it has been proposed that IOL may arise from adipose tissue of bone marrow, the origin and cause of IOL are uncertain1-3'6. An intriguing possibility that should be considered, however, is that IOL might correspond to osteoporotic bone marrow defects containing yellow marrow. Cases of IOL in-
view of the literature. Jpn J Oral Maxillofac Surg 1982: 28:1149 59. 6. SCHAJOWICZ E Histological typing of bone tumours. 2nd ed. Berlin: SpringerVerlag, 1993: 30. 7. SALZER M, SALZER-KUNTSCHIKM. Zur
Frage der sogenannten zentralen Knochenlipoma. Beitr Path Anat 1965: 132: 365-75. 8. To WH, YELrN~KH. Intraosseous lipoma of maxillary tuberosity. Br J Oral Maxillofac Surg 1991: 30: 122-4.
Address: Dr Hideaki Sakashita, DDS, PhD Department of Dentistry and Oral Surgery Ishikawa PreJectural Central Hospital Nu-153, Minamishinbo-machi Kanazawa, Ishikawa 920 Japan