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Soft-tissue chondroma of the masticatory space
Int. J. Oral Maxillofac. Surg. 2007; 36: 174–176 doi:10.1016/j.ijom.2006.07.006, available online at http://www.sciencedirect.com
Case Report Clinical Pathology
Soft-tissue chondroma of the masticatory space
G. De Riu1, S. M. Meloni2, R. Gobbi1, M. Contini3, A. Tullio1 1 Department of Maxillofacial Surgery, University of Sassari, Sassari, Italy; 2 Department of Dentistry, University of Sassari, Sassari, Italy; 3Department of Surgical Pathology, Sassari, Italy
G. De Riu, S. M. Meloni, R. Gobbi, M. Contini, A. Tullio: Soft-tissue chondroma of the masticatory space. Int. J. Oral Maxillofac. Surg. 2007; 36: 174–176. # 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Abstract. Soft-tissue chondroma is an infrequent, benign, cartilaginous tumour that is uncommon in the head and neck region. Single-location chondromas rarely evolve into malignant neoplasms. Chondromas are composed of hyaline cartilage with focal calcification. There have been a few reports published of cases of soft-tissue chondroma of the neck and parapharyngeal space. Here is described a new location of this tumour in the masticatory space.
Accepted for publication 4 July 2006 Available online 27 September 2006
A soft-tissue chondroma is a rare, benign, cartilaginous tumour that occurs predominantly in the hands and feet3. Less common locations are the abdominal wall10, head and neck1. In the head and neck, the most frequent locations are the nasal cavity, paranasal sinuses and larynx. Other locations are extremely rare2. A soft-tissue chondroma is formed of mature hyaline cartilage, containing a few normal chondrocytes. In bone, it is usually located in the medullary cavity, and rarely on the bone surface5. A soft-tissue location is extremely uncommon. Chondromas can be single or multiple. Some syndromes, such as Ollier’s disease and Maffucci’s syndrome, are characterized by multiple chondromas, sometimes in association with benign vascular tumours. A single chondroma is a benign neoformation that rarely evolves into a malignant neoplasm, whereas multiple chondromas transform into chondrosarcoma in almost one-third of syndromic cases5. There have been few reports of softtissue chondromas of the neck and para-
mouth was seen. No neck lymph nodes were palpable. Oral examination revealed a small swelling in the right mandibular ramus extending to the masticatory space. The mucosa covering this area was normal. The mass was palpable, firm, hard, non-pulsating and 3–4 cm in diameter. A general physical examination did not disclose any abnormalities, and there was no history of weight loss. The patient underwent computed tomography (CT) of the head and neck. This showed a circular radiopaque lesion with defined calcified borders localized between the temporal and pterygoid muscles, contiguous with the upper mandibular ramus and medial condyle, and displacing the neighbouring structures (Figs 1 and 2). The mass was not associated with bony erosion. On the basis of the clinical and radiographical findings, a preoperative diagnosis of a solid benign tumour of the masticatory space was made. The patient underwent surgical removal of the mass under general anaesthesia
0901-5027/020174 + 03 $30.00/0
pharyngeal space. Here is described the first case, to the authors’ knowledge, of a soft-tissue chondroma of the masticatory space. Case report
A 47-year-old Caucasian man was referred by the Department of Neurosurgery because of an incidental radiological report of a radiopaque mass seen on a standard lateral X-ray of the cervical spine, obtained following a road accident. The radiograph showed a round mass, about 3.5 cm in diameter, at the level of the right temporomandibular joint (TMJ), medial to the internal aspect of the mandibular ramus. There was no history of previous trauma to the face or neck, and there were no complaints of TMJ pain, voice change, dysphagia or difficulty with neck movements. The clinical examination did not reveal any asymmetry of the face or deformation in this region. No lateral deviation of the mandible or deficit in opening the
# 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Soft-tissue chondroma of the masticatory space
Fig. 1. Preoperative CT.
Fig. 2. Preoperative 3D CT.
Fig. 3. Chondroma after surgical removal.
175
using a transcervical approach without lip splitting. An anterior paramedial osteotomy was performed between the second lower incisor and canine. After the mandible was split and elevated, the masticatory space was exposed widely, allowing easy access to the tumour, which was then removed under direct vision while preserving the surrounding structures. The mandible was then fixed in its original position. The macroscopic examination demonstrated a solid lesion with a 3.5-cm maximum diameter (Fig. 3). The cystic wall was thickened, with calcified areas that resulted in a gritty sensation on sectioning. The histological examination showed a clearly demarcated, circumscribed tissue lesion encapsulated by a thin fibrous layer of connective tissue. The tumour was composed mainly of mature cartilage with a lobular architecture and low cellularity, showing fine calcification (Fig. 4). Individual lobules were distributed within a hyaline matrix with foci of myxoid change. Foci of calcification and ossification were present. Chondrocytes were aggregated in clusters with no nuclear pleomorphism or size variation. There was no binucleation or multinucleation, and the appearance was that of an ossifying chondroma. Histochemistry was performed with a polyclonal antibody against S-100 protein (DAKO, dilution 1:400) and a monoclonal antibody against vimentin (BioGenex, dilution 1:100). The chondrocytes were diffusely positive for these antibodies. Discussion
The masticatory space is delimited by the superficial layer of the deep cervical fascia and includes the masseter, temporal, and lateral and medial pterygoid muscles, and the mandibular ramus. The parapharyngeal space is medial to the internal pterygoid fascia, and the masticatory space is lateral to it. The masticatory space contains an important structure, the oval foramen, through which tumours can invade the brain via perineural diffusion. The aetiology of soft-tissue chondroma is uncertain. It is theorized that these lesions arise from residual embryonic tissue or that they are metaplastic pluripotential mesenchymal cells9. The pathological features of chondromas vary considerably from case to case. Some tumours show focal fibrosis, ossification or myxoid change. Chondromas can be very cellular, with mild-to-moderate nuclear pleomorphism and scattered mitosis. These features result in a confusing histopatholo-
176
De Riu et al.
3.
4. 5.
6. 7. Fig. 4. Microscopic aspect of the chondroma. 8.
gical appearance, including dystrophic calcification, endochondral ossification, haemorrhagic and myxoid degeneration, and granulomatous inflammation1,4. Approximately 10% of soft-tissue chondromas contain osteoclast-like multinucleated giant cells or epithelioid histiocytes with granuloma-like proliferation. Regarding the mechanism of onset of a chondroma in the masticatory space, hypotheses include aberrant embryonic cartilage and metaplasia owing to chronic inflammation. Clinically, like chondromas of the parapharyngeal space, this tumour presented with a slow rate of growth and did not cause pain. Ultimately, it might have caused symptoms, as in the case of developing parapharyngeal tumours, which can also cause upper respiratory obstruction9. In this case, the patient was asymptomatic, and no clinical signs were evident. Owing to the benign nature of this tumour, a conservative approach was indicated, although the high and deep location of the tumour required a wide exposure and external access. An intraoral approach to
the medial condylar region does not allow complete control of the posterior aspects of the neoplasia and is not without risk to the internal maxillary artery, mandibular nerve and other surrounding structures. A mandibular swing was adopted, without the need to split the lip8. This provided a wide exposure of the pterygoid region after splitting and lifting the mandible in the paramidline to avoid damage to the incisors7. If it had been necessary to extend the dissection, an osteotomy of the condyle was planned, as described by SEWARD6. At the 12-month follow-up, there were no signs of recurrence of the neoplasia. The patient showed no functional limitation or aesthetic defect, and there was no evidence of complications. References 1. Chung EB, Enzinger FM. Chondroma of soft parts. Cancer 1978: 41: 1414– 1424. 2. Ikeda K, Kikuta N, Sasaki Y, Kusakari J, Hozawa K, Kawase T. Extra-
9.
10.
cranial chondroma of the skull base. Arch Otorhinolaryngol 1987: 243: 424–428. Kransdorf MJ, Meis JM. Extraskeletal osseus and cartilaginous tumour of extremities. Radiographics 1978: 3: 853–884. Kumar V, Cotran RS. Robbins SL: Robbins Pathologic Basis of Diseases. WB Saunders 1994: p. 757. Onodera K, Xu H, Kimizuka S, Echigo S, Ooya K. Chondroma of the cheek: a case report. Int J Oral Maxillofac Surg 2005: 34: 924–926. Seward GR. Tumours of the parapharyngeal space. J R Coll Surg Edinb 1989: 34: 111–112. Shohat I, Yahalom R, Bedrin L, Taicher S, Talmi YP. Midline versus paramidline mandibulotomy: a radiological study. Int J Oral Maxillofac Surg 2005: 34: 639–641. Spiro RH, Gerold FP, Strong EW. Mandibular ‘‘swing’’ approach for oral and oropharyngeal tumors. Head Neck Surg 1981: 3: 371–378. Wang DH, Guan XL, Xiao LF, Zhang XP, Chen MG, Sun KM. Soft tissue chondroma of the parapharyngeal space: a case report. J Laryngol Otol 1998: 112: 294–295. Widdowson DJ, Lewis-Jones HG. Case report: a large soft-tissue chondroma arising from the posterior mediastinum. Clin Radiol 1988: 39: 333–335.
Address : Giacomo De Riu U.O. Chirurgia Maxillo-Facciale Istituto di Clinica Odontoiatrica Policlinico Universitario Viale San Pietro 43/B 07100 Sassari Italy Tel.: +39 079 228216 Fax: +39 079 229002 E-mail: [email protected]
Case Report Clinical Pathology
Soft-tissue chondroma of the masticatory space
G. De Riu1, S. M. Meloni2, R. Gobbi1, M. Contini3, A. Tullio1 1 Department of Maxillofacial Surgery, University of Sassari, Sassari, Italy; 2 Department of Dentistry, University of Sassari, Sassari, Italy; 3Department of Surgical Pathology, Sassari, Italy
G. De Riu, S. M. Meloni, R. Gobbi, M. Contini, A. Tullio: Soft-tissue chondroma of the masticatory space. Int. J. Oral Maxillofac. Surg. 2007; 36: 174–176. # 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Abstract. Soft-tissue chondroma is an infrequent, benign, cartilaginous tumour that is uncommon in the head and neck region. Single-location chondromas rarely evolve into malignant neoplasms. Chondromas are composed of hyaline cartilage with focal calcification. There have been a few reports published of cases of soft-tissue chondroma of the neck and parapharyngeal space. Here is described a new location of this tumour in the masticatory space.
Accepted for publication 4 July 2006 Available online 27 September 2006
A soft-tissue chondroma is a rare, benign, cartilaginous tumour that occurs predominantly in the hands and feet3. Less common locations are the abdominal wall10, head and neck1. In the head and neck, the most frequent locations are the nasal cavity, paranasal sinuses and larynx. Other locations are extremely rare2. A soft-tissue chondroma is formed of mature hyaline cartilage, containing a few normal chondrocytes. In bone, it is usually located in the medullary cavity, and rarely on the bone surface5. A soft-tissue location is extremely uncommon. Chondromas can be single or multiple. Some syndromes, such as Ollier’s disease and Maffucci’s syndrome, are characterized by multiple chondromas, sometimes in association with benign vascular tumours. A single chondroma is a benign neoformation that rarely evolves into a malignant neoplasm, whereas multiple chondromas transform into chondrosarcoma in almost one-third of syndromic cases5. There have been few reports of softtissue chondromas of the neck and para-
mouth was seen. No neck lymph nodes were palpable. Oral examination revealed a small swelling in the right mandibular ramus extending to the masticatory space. The mucosa covering this area was normal. The mass was palpable, firm, hard, non-pulsating and 3–4 cm in diameter. A general physical examination did not disclose any abnormalities, and there was no history of weight loss. The patient underwent computed tomography (CT) of the head and neck. This showed a circular radiopaque lesion with defined calcified borders localized between the temporal and pterygoid muscles, contiguous with the upper mandibular ramus and medial condyle, and displacing the neighbouring structures (Figs 1 and 2). The mass was not associated with bony erosion. On the basis of the clinical and radiographical findings, a preoperative diagnosis of a solid benign tumour of the masticatory space was made. The patient underwent surgical removal of the mass under general anaesthesia
0901-5027/020174 + 03 $30.00/0
pharyngeal space. Here is described the first case, to the authors’ knowledge, of a soft-tissue chondroma of the masticatory space. Case report
A 47-year-old Caucasian man was referred by the Department of Neurosurgery because of an incidental radiological report of a radiopaque mass seen on a standard lateral X-ray of the cervical spine, obtained following a road accident. The radiograph showed a round mass, about 3.5 cm in diameter, at the level of the right temporomandibular joint (TMJ), medial to the internal aspect of the mandibular ramus. There was no history of previous trauma to the face or neck, and there were no complaints of TMJ pain, voice change, dysphagia or difficulty with neck movements. The clinical examination did not reveal any asymmetry of the face or deformation in this region. No lateral deviation of the mandible or deficit in opening the
# 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Soft-tissue chondroma of the masticatory space
Fig. 1. Preoperative CT.
Fig. 2. Preoperative 3D CT.
Fig. 3. Chondroma after surgical removal.
175
using a transcervical approach without lip splitting. An anterior paramedial osteotomy was performed between the second lower incisor and canine. After the mandible was split and elevated, the masticatory space was exposed widely, allowing easy access to the tumour, which was then removed under direct vision while preserving the surrounding structures. The mandible was then fixed in its original position. The macroscopic examination demonstrated a solid lesion with a 3.5-cm maximum diameter (Fig. 3). The cystic wall was thickened, with calcified areas that resulted in a gritty sensation on sectioning. The histological examination showed a clearly demarcated, circumscribed tissue lesion encapsulated by a thin fibrous layer of connective tissue. The tumour was composed mainly of mature cartilage with a lobular architecture and low cellularity, showing fine calcification (Fig. 4). Individual lobules were distributed within a hyaline matrix with foci of myxoid change. Foci of calcification and ossification were present. Chondrocytes were aggregated in clusters with no nuclear pleomorphism or size variation. There was no binucleation or multinucleation, and the appearance was that of an ossifying chondroma. Histochemistry was performed with a polyclonal antibody against S-100 protein (DAKO, dilution 1:400) and a monoclonal antibody against vimentin (BioGenex, dilution 1:100). The chondrocytes were diffusely positive for these antibodies. Discussion
The masticatory space is delimited by the superficial layer of the deep cervical fascia and includes the masseter, temporal, and lateral and medial pterygoid muscles, and the mandibular ramus. The parapharyngeal space is medial to the internal pterygoid fascia, and the masticatory space is lateral to it. The masticatory space contains an important structure, the oval foramen, through which tumours can invade the brain via perineural diffusion. The aetiology of soft-tissue chondroma is uncertain. It is theorized that these lesions arise from residual embryonic tissue or that they are metaplastic pluripotential mesenchymal cells9. The pathological features of chondromas vary considerably from case to case. Some tumours show focal fibrosis, ossification or myxoid change. Chondromas can be very cellular, with mild-to-moderate nuclear pleomorphism and scattered mitosis. These features result in a confusing histopatholo-
176
De Riu et al.
3.
4. 5.
6. 7. Fig. 4. Microscopic aspect of the chondroma. 8.
gical appearance, including dystrophic calcification, endochondral ossification, haemorrhagic and myxoid degeneration, and granulomatous inflammation1,4. Approximately 10% of soft-tissue chondromas contain osteoclast-like multinucleated giant cells or epithelioid histiocytes with granuloma-like proliferation. Regarding the mechanism of onset of a chondroma in the masticatory space, hypotheses include aberrant embryonic cartilage and metaplasia owing to chronic inflammation. Clinically, like chondromas of the parapharyngeal space, this tumour presented with a slow rate of growth and did not cause pain. Ultimately, it might have caused symptoms, as in the case of developing parapharyngeal tumours, which can also cause upper respiratory obstruction9. In this case, the patient was asymptomatic, and no clinical signs were evident. Owing to the benign nature of this tumour, a conservative approach was indicated, although the high and deep location of the tumour required a wide exposure and external access. An intraoral approach to
the medial condylar region does not allow complete control of the posterior aspects of the neoplasia and is not without risk to the internal maxillary artery, mandibular nerve and other surrounding structures. A mandibular swing was adopted, without the need to split the lip8. This provided a wide exposure of the pterygoid region after splitting and lifting the mandible in the paramidline to avoid damage to the incisors7. If it had been necessary to extend the dissection, an osteotomy of the condyle was planned, as described by SEWARD6. At the 12-month follow-up, there were no signs of recurrence of the neoplasia. The patient showed no functional limitation or aesthetic defect, and there was no evidence of complications. References 1. Chung EB, Enzinger FM. Chondroma of soft parts. Cancer 1978: 41: 1414– 1424. 2. Ikeda K, Kikuta N, Sasaki Y, Kusakari J, Hozawa K, Kawase T. Extra-
9.
10.
cranial chondroma of the skull base. Arch Otorhinolaryngol 1987: 243: 424–428. Kransdorf MJ, Meis JM. Extraskeletal osseus and cartilaginous tumour of extremities. Radiographics 1978: 3: 853–884. Kumar V, Cotran RS. Robbins SL: Robbins Pathologic Basis of Diseases. WB Saunders 1994: p. 757. Onodera K, Xu H, Kimizuka S, Echigo S, Ooya K. Chondroma of the cheek: a case report. Int J Oral Maxillofac Surg 2005: 34: 924–926. Seward GR. Tumours of the parapharyngeal space. J R Coll Surg Edinb 1989: 34: 111–112. Shohat I, Yahalom R, Bedrin L, Taicher S, Talmi YP. Midline versus paramidline mandibulotomy: a radiological study. Int J Oral Maxillofac Surg 2005: 34: 639–641. Spiro RH, Gerold FP, Strong EW. Mandibular ‘‘swing’’ approach for oral and oropharyngeal tumors. Head Neck Surg 1981: 3: 371–378. Wang DH, Guan XL, Xiao LF, Zhang XP, Chen MG, Sun KM. Soft tissue chondroma of the parapharyngeal space: a case report. J Laryngol Otol 1998: 112: 294–295. Widdowson DJ, Lewis-Jones HG. Case report: a large soft-tissue chondroma arising from the posterior mediastinum. Clin Radiol 1988: 39: 333–335.
Address : Giacomo De Riu U.O. Chirurgia Maxillo-Facciale Istituto di Clinica Odontoiatrica Policlinico Universitario Viale San Pietro 43/B 07100 Sassari Italy Tel.: +39 079 228216 Fax: +39 079 229002 E-mail: [email protected]