|Year : 2022 | Volume
| Issue : 3 | Page : 641-649
Lesions in the parotidomasseteric domain: A plethora of diversity
Srivalli Natarajan, Yash Oswal, Adil Gandevivala, Padmakar Sudhakar Baviskar, Sagar Vaishampayan, Sushrut Vaidya, Gaurav Deshpande, Sunil Sidana
Department of Oral and Maxillofacial Surgery, MGM Dental College and Hospital, Navi Mumbai, Maharashtra, India
|Date of Submission||09-Mar-2020|
|Date of Decision||24-Dec-2021|
|Date of Acceptance||18-Mar-2022|
|Date of Web Publication||2-Nov-2022|
Dr. Srivalli Natarajan
Department of Oral and Maxillofacial Surgery, MGM Dental College and Hospital, Sector 1, Kamothe, Navi Mumbai - 410 209, Maharashtra
Source of Support: None, Conflict of Interest: None
Context: Swellings in parotidomasseteric region are one of the most intriguing and challenging lesions in the head and neck. Diverse array of diagnosis, striking clinical similarities between different pathologies and anatomical complexity of this region make parotidomasseteric lesions unique. Aims: This article aims to provide a detailed description of various pathologies associated, the diagnostic challenges posed, and the respective management strategies. Settings and Design: The study design involves retrospective observational. Subjects and Methods: Sixteen rare cases of various parotidomasseteric pathologies were reviewed to delineate clinical presentation and characteristic features in diagnostic investigations and subsequent treatment strategies. Statistical Analysis Used: Not applicable. Results: The analysis showed that lesions in the parotidomasseteric region can be categorized into specific entities with distinct but often overlapping clinical features. Given the location and anatomy of the parotidomasseteric region, these lesions can often remain indolent Investigations are fruitful to some extent in determining the expanse of these lesions, however, remain inconclusive in diagnosing the origin and their true nature. Conclusions: The authors conclude that a systematic approach to the diagnosis of a parotidomasseteric lesion is of utmost importance because the differential diagnosis is prodigious. These lesions can be considered very deceptive, demanding surgical intervention and their excision. With the exception of surgical exploration, physical examination remains the most indispensable tool. Hence, a better classification system which determines the treatment required for a particular parotidomasseteric lesion and which correlates the clinical findings with the preoperative investigations will be more beneficial for the operating surgeon.
Keywords: Differential diagnosis, parotid gland, parotidectomy, parotidomasseteric lesion, preauricular
|How to cite this article:|
Natarajan S, Oswal Y, Gandevivala A, Baviskar PS, Vaishampayan S, Vaidya S, Deshpande G, Sidana S. Lesions in the parotidomasseteric domain: A plethora of diversity. J Datta Meghe Inst Med Sci Univ 2022;17:641-9
| Introduction|| |
Parotidomasseteric region is an area bounded anteriorly by the anterior border of the ascending mandibular ramus, posteriorly by the external auditory canal, mastoid process, and upper portion of the sternocleidomastoid muscle, superiorly by the zygomatic arch and inferiorly by the inferior border of the mandible. Swellings in parotidomasseteric region are one of the most intriguing and challenging lesions in the head and neck due to numerous peculiarities. Varied clinical features, together with the relative rarity of a number of parotidomasseteric lesions makes them exceptional. This article, therefore, discusses a variety of parotidomasseteric pathologies, the diagnostic challenge posed, and respective management strategies.
| Subjects and Methods|| |
A retrospective analysis of 16 patients treated in the Department of Oral and Maxillofacial Surgery, with various parotidomasseteric pathologies between January 2015 and June 2017 were evaluated with complete clinical examination and detailed diagnostic investigations. The patients were included in the study based on the peculiar features of their swellings. The study was exempted by the institutional ethical committee for being a retrospective analysis, and patient identity has not been revealed in the manuscript. Patients with incomplete history, with insufficient data of clinical examination, diagnostic investigations, and wherein, a definitive record of final histopathological diagnosis was not available were also excluded from the analysis. Records of basic investigations such as ultrasonography (USG) and/or fine-needle aspiration cytology (FNAC) along with advanced investigations such as computed tomography (CT)/magnetic resonance imaging (MRI)/positron-emission tomography (PET) scan were also assessed for each patient.
| Ethical clearance|| |
The Institutional Ethics Committee of MGM Dental College and Hospital, Mumbai has approved the Research work proposed to be carried out at MGM Dental College. Date :16th July 2018 with Reference no MGM/EC/2018-19/187.
| Results|| |
Among the patient presenting with parotidomasseteric pathologies: two cases belonged to the infectious group [Table 1], Two cases had a cystic lesions [Table 2], Three cases were of pleomorphic adenoma of parotid gland [Table 3], Two cases had pathology related to ductal component of the parotid gland [Table 4], two cases had pathology related to lymphatic component of the parotid gland [Table 5], one had pathology within masseter muscle and the other had unilateral condylar hyperplasia [Table 6], one case belonged to the vascular component of the parotid gland, one was a case of carcinoma ex pleomorphic adenoma and the other was of plexiform neurofibroma of the facial nerve [Table 7].
|Table 3: Varied clinical presentation of pleomorphic adenoma of the parotid gland|
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| Discussion|| |
Lesions in the parotidomasseteric domain have the following distinctiveness:
- Diverse array of diagnosis: this region incorporates assorted structures such as the parotid gland, temporomandibular joint (TMJ), facial nerve and its branches, masseter muscle with underlying mandibular ramus and vascular structures. The lesion from any of these structures may present as a swelling in the above region which can hence pose a diagnostic dilemma and become an arduous task for the clinician to define its origin
- Clinical presentation of most of the lesions have striking similarities
- There is no consistent correlation between the rate of tumor growth and whether a tumor is benign or malignant
- Choice of investigations: many tools have been in use for imaging of parotidomasseteric swellings. USG and FNAC are often used as guiding investigations based on which advanced investigations such as CT/contrast enhanced computed tomography scans, MRI, PET scan, scintigraphy, sialography, biopsy, etc., can be advised. A single investigation is often misleading and inconclusive when dealing with these lesions,
- Operating in parotidomasseteric region is onerous for the surgeon due to the anatomic complexity created by the presence of facial nerve, its branches, and blood vessels.,
Because of all the above factors, provisional diagnosis for each case can be decided keeping into consideration the colossal differential diagnosis of this region [Table 8].,,,, The peculiarity of all the mentioned lesions lies in the fact that they shared a common location and expressed a few common features which obscured the entire clinical picture and made them indistinguishable from each other. Each of them expressed a unique feature:
|Table 8: Differential diagnosis of Parotidomasseteric lesions according to the anatomical site involved,,,,|
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Unlike infections in other orofacial region; parotidomasseteric infections are dangerous since this area is saturated with many important anatomical structures. These infections can often remain undiagnosed unless they involve overlying skin or are associated with some symptoms.
The 2 cases so described had a varying degree of involvement of the underlying tissues [Table 1] and [Figure 1]. Both cases of cysts were associated with the parotid gland. However, one being within the capsule [[Table 2]: Case 1 and [Figure 2] was enucleated, whereas other [[Table 2]: Case 2] being within the gland was treated with superficial parotidectomy. This concluded that defining the exact location of the lesion with respect to the parotid gland would decide the surgical management option. Seven percent of all cases of epidermoid and dermoid cysts occur in the head-and-neck region and only six cases of epidermoid cyst within the parotid gland are mentioned in the English literature, this being the seventh.
|Figure 1: (a) Left profile view of parotid abscess. (b) T2-weighted magnetic resonance imaging image of myofascial oedema showing fluid collection in the subcutaneous region overlying left masseter muscle|
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|Figure 2: (a) Intraoperative photo of epidermoid cyst within right parotid capsule showing intoto excision of lesion. (b) H and E, ×10 stained section showing cystic lumen containing keratinous material and lining of flattened epidermis cells with prominent granular layer. (c) H and E, ×40 stained section showing cystic lumen containing keratinous material and lining of flattened epidermis cells with prominent granular layer|
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All the three cases of pleomorphic adenoma varied in their clinical presentation and symptoms [Table 3] and [Figure 3]. One of them mimicked a malignant lesion. Hence, pleomorphic lesions may be so varied in their manifestations clinically and histopathologically with unity in diversity. FNAC alone may prove indecisive.
|Figure 3: (a) Preauricular region (varied clinical presentation of pleomorphic adenoma of parotid gland). (b) Postauricular region (varied clinical presentation of pleomorphic adenoma of parotid gland). (c) Pre- and post-auricular region (varied clinical presentation of pleomorphic adenoma of parotid gland)|
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Patient who was diagnosed as a salivary duct carcinoma of the parotid gland had a recurrent swelling, documentation of the previous diagnosis, and surgery was absent and was an active case of tuberculosis (TB) confusing the exact pathology [[Table 4]: Case 2 and [Figure 4]]. Also, salivary duct carcinoma of parotid is a rare aggressive entity accounting for only 0.2% of epithelial salivary gland neoplasm. Recurrent lesions are, therefore, more demanding given the fact that the imaging findings and FNAC or incisional biopsy may be ambiguous. Appropriate histopathology and in many cases even immunohistochemistry of the excised specimen becomes mandatory for a definitive diagnosis and further treatment planning.
|Figure 4: (a) Right profile view of salivary duct carcinoma of parotid gland showing multinodular appearance, raised right ear lobe and drooping of corner of mouth. (b) T1-weighted magnetic resonance imaging contrast image showing a isointense lobulated lesion involving both lobes of right parotid gland|
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Clinical presentation and investigations were suggestive of some common localized lesion in the case of non-Hodgkin's lymphoma (NHL) however, the final diagnosis was extremely rare, which was determined only after obtaining a biopsy [[Table 5]: Case 1 and [Figure 5]a]. Only 2%–5% of salivary gland neoplasm are NHL. It becomes paramount to bear in mind the fact that this area may be one of the rare regions bringing to light a more widespread and systemic condition.
|Figure 5: (a) Contrast computed tomography scan of case of non-Hodgkin's lymphoma showing solid homogenous mass with ill-defined border involving both lobes of right parotid gland. (b) T1-weighted magnetic resonance imaging image of case of masseter muscle hypertrophy showing ill-defined hyperintense signal within right masseter muscle near its insertion over mandibular ramus|
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Parotid TB is a rare form of extrapulmonary TB which is often been misdiagnosed and treated surgically. Since the first description of this condition by Von Stubenrauch in 1894 <200 cases have been reported. Although rare, TB should be kept in mind and considered in the differential diagnosis of any patient presenting with parotidomasseteric swelling [[Table 5]: Case 2].
Patient having left idiopathic masseter muscle hypertrophy [[Table 6]: Case 1 and [Figure 5]b] presented with a diffuse painless swelling which became well-defined, hard, and tender on clenching of teeth. Investigations obfuscated the diagnosis leaving surgical exploration to obtain a biopsy as the only choice of diagnosis.
Patient with right condylar hyperplasia had a chief complaint of facial asymmetry. Clinical examination proved to be groundless. A diagnosis was then established based upon the investigations: orthopantomogram, CT and PET scan. Using three-dimensional planning precise osteotomy cuts were customized for the patients, and surgery was done accordingly [[Table 6]: Case 2 and [Figure 6]].
|Figure 6: (a) Frontal view showing facial asymmetry due to right condylar hyperplasia. (b) Modified L-shaped posterior mandibular ramus osteotomy performed on stereolithographic model|
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Although the head-and-neck region is a common site for vascular tumors and malformations their occurrence within the parotid is rare, accounting for only (0.4–0.6)% of all tumors [[Table 7]: Case 1 and [Figure 7]a].
|Figure 7: (a) T2-weighted postcontrast magnetic resonance imaging of right parotid hemangioma showing sequential centripetal enhancement of hyperintense lesion with multiple calcified foci. (b) Frontal view of high-grade carcinoma ex pleomorphic adenoma of right parotid gland. (c) Right profile view of neurofibromatosis of facial nerve|
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Carcinoma ex pleomorphic adenoma has a yearly incidence rate of 0.17 tumors per one million and a prevalence rate of only 5.6 cases/100,000 malignant neoplasms making this lesion an extremely rare entity [[Table 7]: Case 2 and [Figure 7]b].
The incidence of intra-parotid tumors belonging to facial nerve origin is only (0.2–1.5)%. The case of neurofibroma of facial nerve had a congenital swelling, which gradually increased. Although the patient got operated at the age of 2 years the lesion recurred and presented with extensive size [[Table 7]: Case 3 and [Figure 7]c].
Any patient presenting with a parotidomasseteric swelling should undergo a comprehensive history and detailed physical examination. It is crucial to delineate the duration, onset, size changes over time, and laterality of the swelling. Associated symptoms such as pain, facial nerve weakness, overlying skin changes (draining sinus, erythema, oedema), purulent discharge from within the mouth or external auditory canal, dry eyes or fevers and chills, xerostomia, tender TMJs should also be elucidated. Alleviating and exacerbating factors for each associated symptom should be elicited. A recent history of trauma, when applicable, is important to note.
Examination of the parotidomasseteric lesion involves delineating its physical characteristics and anatomic relationships. A meticulous extraoral, intraoral, TMJ and auricular examination is a desideratum.
In a large proportion of cases, a complete physical examination in conjunction with a solid history is sufficient to arrive at a provisional diagnosis.
Given the location and anatomy of the parotiomasseteric region, these lesions can often remain indolent. Investigations are fruitful to some extent in determining the expanse of these lesions but are inconclusive in diagnosing the origin and their true nature. Hence these lesions are considered very deceptive demanding surgical exploration and their excision. Definitive diagnosis can be established only after histopathological examination of the excised mass. This is especially true when dealing with parotid masses. A minimum biopsy for parotid mass is to perform superficial parotidectomy. It implies that the most conservative treatment itself is radical; sacrificing the entire lobe just to arrive at a final diagnosis. However, no single diagnostic modality is accepted unequivocally as a definitive approach to these lesions. Low-cost modalities such as USG and FNAC may be used as a first-line tool, whereas CT, MRI, and other more advanced imaging methods are the workhorses for most tumor characterization and treatment planning.,,
An unerring histopathological diagnosis is fundamental and is often the limiting factor in clinical practice, both as far as concerns the unrivalled management and for the evaluation of the results of treatment.
| Conclusion|| |
The inevitable conclusion is that a systematic approach to the diagnosis of a parotidomasseteric lesion is of utmost importance because the differential diagnosis is prodigious. Clanger can be evaded by adequate anamnesis, physical examination, imaging, and propitious treatment. With the exception of surgical exploration, physical examination remains the most indispensable tool for the experienced surgeon.
Despite the compendium of literature available on various parotidomasseteric lesions and their management, there is the paucity of information which focuses on a treatment-oriented approach to these swellings rather than a histological approach. Hence, a better classification system that determines the treatment required for a particular parotiomasseteric lesion and which co-relates the clinical findings with the preoperative investigations will be more beneficial for the operating surge3on.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Warpeha RL, Wood NK, Goaz PW. Masses in the neck. In: Differential Diagnosis of Oral and Maxillofacial Lesions. 5th
ed. Switzerland: Mosby; 1997. p. 521-39.
Kuan EC, Clair JM. Evaluation of parotid lesions. Otolaryngol Clin North Am 2015;49:313-25.
Speight PM, Barrett AW. Salivary gland tumours. Oral Dis 2002;8:229-40.
Bussu F, Parrilla C, Rizzo D, Almadori G, Paludetti G, Galli J. Clinical approach and treatment of benign and malignant parotid masses, personal experience. Acta Otorhinolaryngol Ital 2011;31:135-43.
Howlett DC, Kesse KW, Hughes DV, Sallomi DF. The role of imaging in the evaluation of parotid disease. Clin Radiol 2002;57:692-701.
Prasad RS. Parotid gland imaging. Otolaryngol Clin North Am 2016;49:285-312.
Babak A, Babak L. Parotid disease. In: Comprehensive Management of Parotid Disorders, Otolaryngology Clinics of North America. North America: Elsevier; 2016. p. 313-25.
Rea PM, McGarry G, Dunn JS. The precision of four commonly used surgical landmarks for locating the facial nerve in anterograde parotidectomy in humans. Ann Anat 2010;192:27-32.
Malik NA. Diseases of the salivary glands. In: Textbook of Oral and Maxillofacial Surgery. 3rd
ed. Delhi: Jaypee Brothers; 2012. p. 585-611.
Arriagada WA, Silva AR, Vargas PA, Lopes MA. Diagnostic approach to intramasseteric nodules. Oral Surg Oral Med Oral Pathol Oral Radiol 2017;123:e16-21.
Roda RP, Bagán JV, Sanchis JM, Margaix M. Pseudotumors and tumors of the temporomandibular joint. A review. Med Oral Patol Oral Cir Bucal 2013;18:e392-402.
James DG. Differential diagnosis of facial nerve palsy. Sarcoidosis Vasc Diffuse Lung Dis 1997;14:115-20.
Savage NW, Boras VV. Unilateral intraparotid swelling: A case report of Kimura's disease and review of differential diagnosis. Case Rep Otolaryngol 2013;2013:795921.
Dutta M, Saha J, Biswas G, Chattopadhyay S, Sen I, Sinha R. Epidermoid cysts in head and neck: Our experiences, with review of literature. Indian J Otolaryngol Head Neck Surg 2013;65:14-21.
Kothandaraman S, Thiagarajan B. A cheesy affair! – Report of a case of an epidermoid cyst of Parotid. Otolaryngol Online J 2013;3:617-9.
Al-Qahtani KH, Tunio MA, Bayoumi Y, Gurusamy VM, Bahamdain FA, Fatani H. Clinicopathological features and treatment outcomes of the rare, salivary duct carcinoma of parotid gland. J Otolaryngol Head Neck Surg 2016;45:32.
Weber AL, Rahemtullah A, Ferry JA. Hodgkin and non-Hodgkin lymphoma of the head and neck: Clinical, pathologic, and imaging evaluation. Neuroimaging Clin N Am 2003;13:371-92.
Birkent H, Karahatay S, Akcam T, Durmaz A, Ongoru O. Primary parotid tuberculosis mimicking parotid neoplasm: A case report. J Med Case Rep 2008;2:62.
Sánchez HL, Cagigal BP, Rubiales BM, Hernández AV. Cavernous hemangioma of the parotid gland in adults. J Clin Exp Dent 2014;6:592-4.
Antony J, Gopalan V, Smith RA, Lam AK. Carcinoma ex pleomorphic adenoma: A comprehensive review of clinical, pathological and molecular data. Head Neck Pathol 2012;6:1-9.
Rai A, Kumar A. Neurofibroma of facial nerve presenting as parotid mass. J Maxillofac Oral Surg 2015;14:465-8.
Carlson ER, Webb DE. The diagnosis and management of parotid disease. Oral Maxillofac Surg Clin North Am 2013;25:31-48.
David O, Blaney S, Hearp M. Parotid gland fine-needle aspiration cytology: An approach to differential diagnosis. Diagn Cytopathol 2007;35:47-56.
Biakek EF, Fakubowski W, Zajkowski P, Szopinski K. US of the major sali- vary glands: Anatomy and spatial relationships, pathologic conditions, and pitfalls. Radiographics 2006;26:745-64.
Lee YY, Wong KT, King AD, Ahuja AT. Imaging of salivary gland tumours. Eur J Radiol 2008;66:419-36.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]