Giant cell tumour of a temporomandibular joint presenting as a parotid mass: Case report and analysis of the 19 cases in the literature

Journal of Cranio-Maxillo-Facial Surgery 42 (2014) 1778e1782

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Case report

Giant cell tumour of a temporomandibular joint presenting as a parotid mass: Case report and analysis of the 19 cases in the literature Yun-Chen Huang a, Jeng-Wen Chen a, Yen-Lin Chen b, Pei-Jen Lou c, * a

Department of Otolaryngology, Head and Neck Surgery, Cardinal Tien Hospital, School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan Department of Pathology, Cardinal Tien Hospital, School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan c Department of Otolaryngology, Head and Neck Surgery, National Taiwan University Hospital, School of Medicine, National Taiwan University, Taipei, Taiwan b

a r t i c l e i n f o

a b s t r a c t

Article history: Paper received 6 March 2014 Accepted 5 June 2014 Available online 14 June 2014

Giant cell tumour (GCT) in the parotid region is a rare lesion whose origin can be divided into three compartments: giant cell tumour of the salivary gland (GCT-SG), giant cell tumour of the bone (GCTbone) and giant cell tumour of the soft tissue (GCT-ST). A low risk of malignancy has been observed, in which all of them were GCT-SG. We present a case of GCT in the parotid region and review the features of GCT in origin, immunohistochemical characteristics, treatment of choice and disease outcome. © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Keywords: Giant cell tumour Parotid gland Temporomandibular joint Soft tissue

1. Introduction A parotid mass is a common presenting complaint for head and neck surgeons. The most common benign parotid tumour is the pleomorphic adenoma (Pinkston and Cole, 1999). Some rare extraparotid lesions, arising from the temporomandibular joint or mandible, may also present as a parotid mass and should be considered in the differential diagnosis. Histologically characterized as round to oval-shaped mononuclear cells (MNC) intimately admixed with uniformly scattered multinucleated osteoclast-like giant cells (MOGC), GCT is generally considered a benign tumour originating from the undifferentiated mesenchymal cells of the bone marrow; it is most commonly found in the extremities (Mendenhall et al., 2006; Sethi et al., 2006). Three types of GCT are GCT of the bone, GCT of the tendon sheath and GCT of the soft tissue. Notably, GCT located in the head and neck region is uncommon (Roy et al., 2013). Around the parotid region, only eighteen cases have been reported in English-language literature (Eusebi et al., 1984; Balogh et al., 1985; Batsakis et al., 1988; Ellis et al., 1991; Itoh et al., 1992; Grenko et al., 1993; Donath et al., 1997; Tse et al., 2004; Torabinezad et al., 2006; Kadivar et al., 2007;

* Corresponding author. Department of Otolaryngology, Head and Neck Surgery, National Taiwan University Hospital and National Taiwan University School of Medicine, 7, Chung-Shan South Road, Taipei, Taiwan. Tel.: þ886 2 23123456x65224; fax: þ886 2 23410905. E-mail addresses: [email protected], [email protected] (P.-J. Lou).

Fang et al., 2009; Wu et al., 2012; Yang et al., 2012). According to the anatomic location, GCT in the parotid region can be divided into intraparotid and extraparotid lesions. GCT arises mainly from the parotid gland (i.e., giant cell tumour of the salivary gland, GCT-SG) and is regarded as the intraparotid lesion, but may also arise in the mandible (i.e., giant cell tumour of the bone, GCT-bone), or the soft tissue in the parotid region (i.e., giant cell tumour of the soft tissue, GCT-ST) regarded as extraparotid lesions (Tse et al., 2004; Fang et al., 2009). Ten of the eighteen reported cases were malignant, and all originated from GCT-SG (Eusebi et al., 1984; Balogh et al., 1985; Batsakis et al., 1988; Grenko et al., 1993; Donath et al., 1997; Tse et al., 2004; Torabinezad et al., 2006; Kadivar et al., 2007; Fang et al., 2009; Yang et al., 2012). This finding highlights the importance of the origin of GCT in the parotid region. Given the rarity of the above cases, no consistent treatment guideline has been proposed. Adjuvant radiotherapy was performed in two cases, possibly owing to the radiosensitive nature of the giant cell tumour (Balogh et al., 1985; Kanamori and Ohmori, 2005; Wu et al., 2012). Based on the case study reported in this study, the 19th case of GCT in the parotid region is demonstrated and related literature is reviewed as well. 2. Case report A 41-year-old man presented to our clinic with a nonprogressive, painless and indurate mass in the right parotid region for five months. The lesion was traced back to seven months

http://dx.doi.org/10.1016/j.jcms.2014.06.014 1010-5182/© 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Y.-C. Huang et al. / Journal of Cranio-Maxillo-Facial Surgery 42 (2014) 1778e1782

before admission when the right parotid mass was noted. He first received partial excision of the right parotid mass at another hospital. The pathological diagnosis was GCT-ST. Postoperatively, induration was still found in the right parotid area. The patient came to our hospital for a second opinion, when physical examination revealed a 2  2 cm painless indurate mass in the right parotid area with a previous surgical scar. Examination of the head and neck, including nasopharynx, oral cavity, hypopharynx, and larynx were unremarkable. Routine blood chemistry tests were normal. Magnetic resonance imaging revealed a 2 cm mass with T1W isosignal and T2W hyposignal adjoining to the mandible bone in the area corresponding to the parotid gland on the right side (Fig. 1). Heterogeneous enhancement of the mass was noted. A skin incision was made from anterior to the right ear to the mandibular margin. The tumour was extraparotid and was located beneath the zygomatic and temporal branches of facial nerves, firmly adhering to the temporomandibular joint capsule (Fig. 2A). The tumour was then resected completely along with a portion of the temporomandibular joint capsule. Notably, the tumour did not involve the mandible. The zygomatic and temporal branches of facial nerve were well preserved (Fig. 2C). Postoperatively, facial palsy was mild and gradually improved. Gross examination revealed a brown and elastic mass, measuring up to 2.5  1.2  0.9 cm in size (Fig 3A). The microscopic examination in Fig. 3B indicated a giant cell-rich lesion characterized by a multinodular architecture, with cellular nodules separated by fibrous tissue septa. The nodules consisted of a mixture of round to oval cells that were MNC and MOGC, both of which had similar nuclei and were immersed in richly vascularized stroma. Immunohistochemically, CD68 highlighted the MOGC and a minor portion of MNC (Fig. 3C). S-100 and cytokeratin were both negative (data not shown). The margin was free of tumour involvement. The diagnosis was GCT-ST (the temporomandibular joint capsule) in the right parotid region. The patient had no facial palsy and no parotid mass at 14-months follow up examination. 3. Discussion Neoplasms in the parotid region arise mainly from the parotid gland and are usually benign. The most common tumour is pleomorphic adenoma, accounting for approximately 53.3% of all parotid gland neoplasm. It is followed by Warthin tumour, which accounts for approximately 28.3% of all parotid gland neoplasm. Only 14.6% of the parotid gland neoplasms are malignant (Pinkston and Cole, 1999). Some rare extraparotid lesions, originating from the surrounding tissue of the parotid gland (e.g., the

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temporomandibular joint or mandible) also present as a parotid mass and should be considered in the differential diagnosis because the incidence of malignancy and treatment might differ from other lesions. Eusebi et al. (1984) first reported three cases of GCT in the parotid region with an unclear origin. Histologically characterized as a round to oval-shaped MNC intimately admixed with uniformly scattered MOGC, GCT is generally considered a benign tumour originating from the undifferentiated mesenchymal cells of the bone marrow; this tumour is most commonly found in the extremities (Mendenhall et al., 2006; Sethi et al., 2006). GCT outside the bone is histologically similar to GCT of the bone, and possibly occurring in the soft tissue (Trabelsi et al., 2009) and in visceral organs such as the pancreas (Silverman et al., 1990), thyroid (Cibull and Gray, 1978), and liver (Matsumoto et al., 2012). Therefore, we can infer that GCT can arise from the bone or soft tissue adjacent to the parotid gland. Including the current case, only nineteen cases of GCT located in the parotid region have been reported in the English-language literature. In addition to reporting this rare case, we also demonstrated the surgical intervention rarely found in the literature (Itoh et al., 1992). As shown in Table 1, most patients (16/19) reviewed in the literature were males, with their ages ranging from 30 to 92 years. Ten cases were found to be malignant. Of the malignant components within GCT, six cases were salivary duct carcinoma (Balogh et al., 1985; Batsakis et al., 1988; Grenko et al., 1993; Tse et al., 2004; Kadivar et al., 2007; Fang et al., 2009); two cases were carcinoma ex pleomorphic adenoma (Eusebi et al., 1984; Donath et al., 1997); and two cases revealed carcinoma without definite pathological diagnosis (Torabinezad et al., 2006; Yang et al., 2012). All malignant components within GCT in the parotid region were carcinoma. Cervical lymph node metastasis was present in one case (Kadivar et al., 2007). Additionally, lung metastasis was reported in two cases, and both of them died with disease (Balogh et al., 1985; Grenko et al., 1993). Most cases received surgical intervention alone with only two cases receiving adjuvant radiotherapy (Balogh et al., 1985; Wu et al., 2012). No recurrence case was reported. Although GCT of the bone or soft tissue can harbour a malignant tumour, the malignancy is invariably sarcoma rather than carcinoma (Bertoni et al., 2003; Tse et al., 2004). However, all malignant components within GCT in the parotid region were carcinoma. Additionally, in certain malignant cases with salivary duct carcinoma, previous studies demonstrated that the carcinomatous component has genotyping analysis similar to that of mononuclear cells (Balogh et al., 1985; Batsakis et al., 1988; Grenko et al., 1993; Tse et al., 2004; Kadivar et al., 2007; Fang et al., 2009). This finding suggests a possible origin from the parotid gland. In two

Fig. 1. Magnetic resonance imaging findings. The mass, measuring 2 cm in size, adjoining to the mandible condyle was hyposignal in T2W (A) and isosignal in T1W (B). Heterogeneous enhancement of the mass in T1W with contrast (C).

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Fig. 2. Operative findings. The tumour was located beneath the zygomatic and temporal branches of facial nerves, firmly adhering to the temporomandibular joint capsule (A). The mandible bone was not involved by the tumour (B). The zygomatic and temporal branches of facial nerves were well preserved (C).

Fig. 3. Pathological findings. Gross examination indicated a brown and elastic mass, measuring up to 2.5  1.2  0.9 cm in size (A). Microscopic examination revealed a mixture of mononuclear cells and multinucleated cells, both of which have a similar nuclei (B) and were both immunoreactive for CD68 (C).

other cases (Eusebi et al., 1984; Donath et al., 1997), the carcinomatous component was carcinoma ex pleomorphic adenoma. As is generally assumed to arise from the parotid gland rather than the bone or soft tissue, these studies did not describe operative findings or genetic evidence. In a case reported by Itoh et al., the tumour was found to adhere to the cheek bone; in

addition, histological examination revealed a mixture of MNC and MOGC without glandular tissue. The operative findings revealed a possible origin from the cheek bone. In our case, the operative findings showed that the tumour firmly adhered to the temporomandibular joint capsule (Fig. 2A) with no involvement of intraarticular structure and mandible. This finding is consistent with

Table 1 Literature review of 19 cases. Authors

Year

Cases reported

Age/sex

Malignant component within GCT

Treatment

Metastasis

Outcome (month)

Eusebi et al. (1984)

1984

3

Balogh et al. (1985) Batsakis et al. (1988)

1985 1988

1 2

Ellis et al. (1991)

1991

3

Itoh et al. (1992) Grenko et al. (1993) Donath et al. (1997) Tse et al. (2004) Torabinezad et al. (2006) Kadivar et al. (2007) Fang et al. (2009) Yang et al. (2012) Wu et al. (2012) Huang et al. (New case)

1992 1993 1997 2004 2006 2007 2009 2012 2012 2013

1 1 1 1 1 1 1 1 1 1

30/M 52/M 43/M 67/M 59/M 92/M 70/F 65/M 73/M 53/M 66/F 82/M 75/M 35/F 75/M 43/M 57/M 57/M 41/M

e e CXPA Ductal carcinoma Ductal carcinoma e e e e e Salivary duct carcinoma CXPA Salivary duct carcinoma Not specified Salivary duct carcinoma Salivary duct carcinoma Not specified e e

Surgery Surgery Surgery Surgery & R/T Surgery Surgery NA NA NA Surgery Surgery NA Surgery Surgery Surgery Surgery Surgery & R/T Surgery Surgery

e e e Lung e e e e e e Lung e e e Cervical lymph node e e e e

NED/48 NED/48 NED/60 DWD/28 NED/12 NED/9 NA NA NA NA DWD/13 NA NA NA NA NED/12 NA NA NED/14

DWD, died with disease; F, female; M, male; NA, not available; NED, no evidence of disease; CXPA, carcinoma ex pleomorphic adenoma; R/T, radiotherapy.

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Table 2 Clinical and pathological characteristics of giant cell tumour in the parotid region. Types

Operative findings

H&E stain

Immunohistochemical characteristics

Malignancy

GCT-SG GCT-Bone GCT-ST

Intraparotid lesion Extraparotid lesion Extraparotid lesion

Nuclear irregularity in MNC Similar nuclei in MNC and MOGC Similar nuclei in MNC and MOGC

MNC: Epithelial marker (þ) MOGC: CD68(þ) MNC & MOGC: Epithelial marker () CD68(þ) MNC & MOGC: Epithelial marker () CD68(þ)

52% (10/19) of malignancy No report No report

GCT-SG, giant cell tumour of the salivary gland; GCT-bone, giant cell tumour of the bone; GCT-ST, giant cell tumour of the soft tissue; MNC, mononuclear cells; MOGC, multinucleated osteoclast-like giant cells.

the diagnosis of GCT of the soft tissue. More precisely, the diagnosis is GCT of the temporomandibular joint capsule. Consequently, the origin of GCT located in the parotid region arises mainly from the parotid gland (GCT-SG), mandible (GCTbone), or soft tissue surrounding the parotid region (GCT-ST). Several differences arise between GCT of different origins in the parotid region. First, from an anatomical aspect, GCT-bone and GCTST are extraparotid tumours originating from the bone or soft tissue adjacent to the parotid gland. Operative findings reveal the tumour adheres to their origin and there is distinction between it and the parotid gland (Itoh et al., 1992; Kadivar et al., 2007). Second, as proposed by Tse et al. (2004) and Fang et al. (2009), GCT-bone or GCT-ST, in which the nuclei of MNC and MOGC are similar to each other; in addition, these two cells are positive for CD68 and negative for epithelial markers. Conversely, the nuclei of MNC in GCT-SG do not resemble those of MOGC, show at least some nuclear irregularity, and are immunoreactive for epithelial markers (Tse et al., 2004; Kadivar et al., 2007; Yang et al., 2012). This finding might explain the MNC in GCT-SG are of epithelial origin and are generally viewed as the carcinomatous origin (Balogh et al., 1985; Batsakis et al., 1988; Tse et al., 2004). Third, all of the malignant cases of GCT in the parotid region are GCT-SG. Tse et al. further demonstrated a similar genotyping analysis between the MNC and the salivary duct carcinoma component, indicating a similar pathogenesis in those two components. For brevity, according to Table 2, GCT-bone and GCT-ST in the parotid region are assumed to be extraparotid benign lesions. In contrast, GCT-SG is more aggressive and could be considered as potential malignancy, owing to the high risk of associated carcinomatous component in GCT-SG (Tse et al., 2004). Chondroblastomas are frequently misdiagnosed as GCTs. Because of the anatomical location, chondroblastoma of the temporomandibular joint can present as a parotid mass and should be differentiated from GCT in the parotid region. Chondroblastoma is a chondrogenic tumour derived from cartilaginous components of the mandible condyle (Gaudet et al., 2004). It has also been demonstrated that multinucleated giant cells are seen in chondroblastomas (Goodsell and Hubinger, 1964; Codman, 2006). Although several studies have indicated multinucleated giant cells in chondroblastomas are not as numerous as in GCTs, the microscopic distinction between chondroblastoma and GCT is sometimes difficult (Monda and Wick, 1985; Kurt et al., 1989; Kondoh et al., 2002). S-100 protein has been demonstrated in normal human chondrocytes (Stefansson et al., 1982; Nakamura et al., 1983). The immunoreactivity for S-100 protein was positive in the chondroid tumour cells of chondroblastomas, but was negative in GCTs. Consequently, it has been reported to be a useful diagnostic marker for chondroblastoma (Monda and Wick, 1985). Bui et al. and Kondal et al. had reviewed reported cases of temporomandibular joint chondroblastomas. The age distribution ranged from 27 years to 56 years, with the mean age around 39 (Kondoh et al., 2002; Bui et al., 2009). On the other hand, all GCT cases we reviewed in this study were aged between 30 and 92 years, apparently older than those with chondroblastomas. On surgical findings, chondroblastoma is a tumour arising from the condylar cartilage of the mandible with

possible resorptive defects or invasion to the mandible bone. After analysis of our case and the 18 cases in the literature, all cases showed no involvement of the condylar cartilage of the mandible, ruling out the diagnosis of chondroblastoma. In summary, the age of chondroblastoma patients tends to be younger than those with GCTs, immunostaining of S-100 is commonly positive for chondroblastomas but negative for GCTs, and the mandible condyles are involved in chondroblastomas but were normally spared in GCTs. Microscopic findings of mixture MNC and MOGC confirm the diagnosis of GCT. To differentiate the origin from the parotid gland, mandible or soft tissue lies in operative findings and a detailed histological review of the difference between MNC and MOGC. Preoperative fine needle aspiration was performed in three cases (Torabinezad et al., 2006; Kadivar et al., 2007; Yang et al., 2012). The cytological findings revealed MNC and MOGC with atypical nuclei. As GCT-SG is assumed to have a higher risk of malignancy, operative findings help to differentiate the origin. Detailed information provided by surgeons can remind pathologists to perform a diligent search for the small and focal carcinomatous components in GCT within parotid (GCT-SG) (Tse et al., 2004; Kadivar et al., 2007; Yang et al., 2012). A literature review has demonstrated long disease-free survival, low metastasis rate, and no recurrence after complete excision, even among the malignant cases. The benefit of adjuvant radiotherapy is difficult to evaluate because of the limited number of cases.

4. Conclusion GCT in the parotid region is rare and can be classified as GCT-SG, GCT-bone and GCT-ST. Careful screening for the carcinomatous component is essential in GCT-SG, which can be more aggressive. Metastasis is less frequent and the prognosis is excellent among all three origins of GCT, even in malignant cases. Given the limited evidence of the benefit provided by adjuvant radiotherapy, complete excision remains the treatment of choice. Both operative and histological findings are essential to identify the tumour origin. Importantly, close communication between surgeons and pathologists in these rare cases is of priority concern when making the correct diagnosis.

Conflict of interest The authors declare that they have no competing interests.

Financial disclosure Nil.

Acknowledgements Pin-Hsin Chen, National Taiwan University medical student, is appreciated for her assistance in collecting clinical images.

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