Indian Journal of Dental ResearchIndian Journal of Dental ResearchIndian Journal of Dental Research
Indian Journal of Dental Research   Login   |  Users online: 1524

Home Bookmark this page Print this page Email this page Small font sizeDefault font size Increase font size         


Table of Contents   
Year : 2011  |  Volume : 22  |  Issue : 4  |  Page : 617
Cysticercosis of masseter

1 Department of Dentistry, Seven Hills Hospital, Mumbai, India
2 Department of Dentistry, Karuna Hospital, Mumbai, India
3 Department of Oral Pathology, Terna Dental College and Hospital, Nerul, Navi Mumbai, India

Click here for correspondence address and email

Date of Submission21-Sep-2010
Date of Decision18-Jan-2011
Date of Acceptance15-Mar-2011
Date of Web Publication26-Nov-2011


Cysticercosis is a parasitic infestation caused by the larval stage of Taenia solium, a cestodic paratise. It is a common disease in developing countries where it is also endemic. The most commonly infested body organs include subcutaneous tissues, brain and skeletal muscles. It is interesting to note that oral lesion of cysticercosis is a rare event. Here we report an isolated lesion of cysticercosis in the masseter muscle.

Keywords: Masseter muscle, oral cysticercosis, Taenia solium

How to cite this article:
Kumar B D, Dave B, Meghana S M. Cysticercosis of masseter. Indian J Dent Res 2011;22:617

How to cite this URL:
Kumar B D, Dave B, Meghana S M. Cysticercosis of masseter. Indian J Dent Res [serial online] 2011 [cited 2019 Oct 19];22:617. Available from:
Cysticercosis is an infestation caused by the larval stage of the tapeworm, Taenia solium, a cestode measuring about 2.5-3.0 m. [1] Human beings serve as either a definitive or an intermediate host of the adult tapeworm. T. solium has a complex life cycle requiring two mammalian hosts: A definitive host, in which the worm reaches sexual maturity, and an intermediate host. [1] Humans are the only definitive hosts for the adult T. solium. [1] Consumption of inadequately cooked pork is the primary cause because pigs serve as normal intermediate hosts. Cysticercosis is endemic to developing countries (mainly India, Indonesia, China, Africa, Peru and Mexico) but may also occur in non-endemic areas. [2] Oral cysticercosis is very rare in spite of the abundance of muscular tissue in the oral and maxillofacial region and is usually asymptomatic. According to the literature reports, the prevalence of oral cysticercosis is 4.1%. [3] The most likely involved intraoral sites include buccal mucosa, tongue and lips. [4],[5] Here, we report an isolated lesion of cysticercosis involving the masseter muscle.

   Case Report Top

An 18-year-old female patient reported with a complaint of swelling in her right cheek. She gave a history of intermittent increase in the size of swelling accompanied by pain since the past 1 year. Her past medical history was noncontributory.

On extraoral examination, the face appeared symmetrical and the overlying facial skin appeared normal. Intraoral examination revealed a mild swelling of the right cheek. Bimanual palpation of right masseter muscle revealed a well-defined, nontender, mobile nodule of approximately 1.5 cm in diameter, which became less prominent on clenching of teeth. No limitation in mandibular movement was noted. Neither any palpable lymph node was present in the head and neck nor any neurological deficit was seen. The oral mucosa appeared normal with minimal inflammatory changes. The salivary flow from the right Stensen's duct appeared normal.

Ultrasonography (USG) of the right cheek revealed a 1.2 × 0.8 cm, well-defined cystic lesion with a central echogenic area within it. Absence of vascularity was noted. The USG gave the impression of cysticercosis in the masseter muscle, following which USG-guided fine needle aspiration cytology (FNAC) was performed. The aspirate obtained was clear. The smear showed mixed inflammatory cell infiltrate and histiocytic clusters with an occasional fragment of muscle fiber. There was no evidence of any parasite in that aspirate. A magnetic resonance image (MRI) was done which showed an irregularly marginated, well-encapsulated, low attenuation, peripherally enhancing cyst of approximately 10 mm in diameter within the right masseter. It showed an eccentrically located focus of different signal characteristics [Figure 1] and [Figure 2]. The patient was scheduled for excisional biopsy under general anesthesia. A well-encapsulated cystic lesion, milky white in color was identified which was not attached to the masseter muscle. The lesion was removed in toto. The postoperative course was uneventful.
Figure 1: T2W MRI image showing hypointense well-defined lesion in the bulk of right masseter muscle (arrow)

Click here to view
Figure 2: T2W fat-suppressed MRI image showing edema surrounding the hypointense lesion and calcification within the lesion (arrow)

Click here to view

Histopathologic examination

The gross specimen revealed a whitish cyst measuring 0.6 × 0.4 × 0.3 cm, yielding a milky white fluid on the cut surface.

On microscopic examination, the H and E stained sections revealed the presence of a fibrous pseudocapsule infiltrated by chronic inflammatory cells. The encysted larva showed a degenerated scolex covered by a wavy, refractile, eosinophilic cuticle. Aggregates of subcuticular cells were also seen along with bundles of smooth muscle fibers in the deeper layers. Areas of calcification were also noted. This confirmed the diagnosis of cysticercosis [Figure 3] and [Figure 4].
Figure 3: The H and E stained section (×10 magnification) shows a fibrous pseudocapsule infiltrated by chronic inflammatory cells. The encysted larva shows a degenerated and ruptured scolex covered by a wavy, refractile, eosinophilic cuticle. Thick collagen fibers and an area of calcification are also seen

Click here to view
Figure 4: The H and E stained section (×40 magnification) shows the degenerated larval capsule infiltrated by chronic inflammatory cells. Aggregates of subcuticular cells are also seen along with abundant bundles of smooth muscle fibers

Click here to view

   Discussion Top

The ingestion of T. solium eggs happens by consumption of fecally contaminated vegetables, food or water, as well as self-contamination by reflux from the intestine into the stomach or by contaminated hands. [4],[6] When a man ingests the eggs, he becomes the intermediate host, a role usually played by the pig, and a larval form develops. The eggs develop into oncospheres that penetrate the intestine wall and reach a destination via lymphatic or vascular circulation where the larvae develop and become the cysticerci or "Bladder worm", a fluid-filled cyst. [1] Cysticerci are spherical, milky white cysts containing fluid and a single invaginated scolex with hooklets. The cyst wall is more than 100-μm thick, rich in glycoproteins and rarely evokes any host reaction when it is intact. [1]

Although any body site can be involved, the subcutaneous tissues, brain and skeletal muscles are the most commonly affected. [1] Oral cysticercosis is an unusual event and is usually asymptomatic. Furthermore, it is interesting to note that involvement of masseter is extremely rare. Reddi et al. (2001) [7] and Mittal et al. (2008) [8] reported similar cases of intramuscular cysticercosis in the masseter muscle, both of which were diagnosed by USG and treated conservatively. The most commonly involved intraoral sites include tongue (42.15%), lips (26.15%) and buccal mucosa (18.9%). [6],[7] The most serious involvement is that of the central nervous system, followed by ocular involvement.

Differential diagnoses of a solitary lesion in the masseter muscle include inflammatory lesions of the parotid gland, neoplasms of accessory parotid gland, main parotid duct obstruction, preauricular lymphadenopathy, primary and metastatic tumors of masseter muscle, sarcoidosis, intramuscular lipomas, and solitary neurogenic tumors such as neurilemmoma, neurofibroma and vascular lesions such as hemangioma or lymphangioma. [6],[7]

Radiography can be a simple and useful tool since it can detect focal areas of calcification caused due to cystic degeneration followed by inflammation and focal scarring. Other diagnostic tests include radiologic imaging (particularly computerized tomography and MRI), serology, and tissue biopsy. Parasitic examinations with zinc sulfate flotation and formalin ether sedimentation technique are also valuable in revealing T. solium eggs in stool samples. [6]

Treatment of cysticercosis is based on the symptoms and the anatomic area involved. No treatment is required for patients with inactive disease. Surgical excision is recommended for ventricular, ocular, spinal and symptomatic subcutaneous cysts. The well-defined capsule permits a complete excision, and recurrence is unlikely if all of the cysts are removed. Perioperative dexamethasone administration may be required to minimize the inflammatory response. Drugs such as praziquantel and albendazole are the two recommended antihelminthic drugs for the treatment of neurocysticercosis. [1]

Prognosis depends on the location of the cysts. Extracranial cysts with viable larvae usually remain asymptomatic. Neurocysticercosis is amenable to cure with antihelmenthic drugs, although fatalities have been reported in a few cases. [1],[2],[4] No further treatment was prescribed and the patient has been advised periodic follow-up or when symptomatic.

   Conclusion Top

Oral solitary lesion in patients living in endemic areas should be considered for a diagnosis of cysticercosis, as emphasized by this case.

   References Top

1.Kumar V, Abbas AK, Fausto N. Pathologic Basis of Disease. In: Robbins SL, Cotran RS editors. Infectious Diseases. 7 th ed. New York: W B Saunders; 2004. p. 406-7.  Back to cited text no. 1
2.Berkow R. The Merck Manual of Diagnosis and Therapy. In: Beers MH editor. The nervous system. 16 th ed. Rahway, New Jersey: Merck; 1992. p.1274-5.  Back to cited text no. 2
3.Nigam S, Singh T, Mishra A, Chaturvedi KU. Oral cysticercosis-report of six cases. Head Neck 2001;23:497-9.  Back to cited text no. 3
4.Fazakerley MW, Woolgar JA. Cysticercosiscellulosae. An unusual cause of a labial swelling. Br Dent J 1991;170:105-6.  Back to cited text no. 4
5.Timosca G, Gavrilita L. Cysticercosis of the maxillofacial region. A clinicopathologic study of 5 cases. Oral Surg Oral Med Oral Path 1974;37:390-400.  Back to cited text no. 5
6.Romero De Leon E, Aguirre A. Oral cysticercosis. Oral Surg Oral Med Oral Path Oral Radiol Endod 1995;79:572-7.  Back to cited text no. 6
7.Reddi SP, Molares MJ, Addante RD. Solitary lesion in the masseter muscle. J Oral Maxillofac Surg 2001;59:71-5.  Back to cited text no. 7
8.Mittal A, Das D, Iyer N, Nagaraj J, Gupta M. Masseter cysticercosis - a rare case diagnosed on ultrasound. Dentomaxillofac Radiol 2008;37:113-6.  Back to cited text no. 8

Correspondence Address:
B Dilip Kumar
Department of Dentistry, Seven Hills Hospital, Mumbai
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0970-9290.90334

Rights and Permissions


  [Figure 1], [Figure 2], [Figure 3], [Figure 4]

This article has been cited by
1 Cysticercosis of the masseter: MRI and sonographic correlation
V Bhat,M Nagarjuna,V Belaval,S Shetty,P C Salins
Dentomaxillofacial Radiology. 2015; 44(5): 20140372
[Pubmed] | [DOI]
2 Solitary Cysticercosis of the Temporalis Muscle: Report of a Rare Case
K. Y. Giri,Sarwar Alam,Ramakant Dandriyal,Subodh S. Natu
Journal of Maxillofacial and Oral Surgery. 2015;
[Pubmed] | [DOI]
3 Cysticercosis of Soleus muscle presenting as isolated calf pain
Pallav Mishra,Divya Pandey,Brajendra N. Tripathi
Journal of Clinical Orthopaedics and Trauma. 2014;
[Pubmed] | [DOI]
4 Cysticercosis Involving Muscle of Mastication: A Review and Report of Two Cases
Sarbjeet Singh,V. Sreenivasan,Kanika Garg,Nikhel Dev Wazir,Jaspal Singh Rajput,Pawandeep Sandhu Virk
Case Reports in Dentistry. 2013; 2013: 1
[Pubmed] | [DOI]
5 cysticercosis involving muscles and liver only: a yet unknown entity
sen, k. and karmakar, p. and bandyopadhyay, a. and santra, t. and sarkar, m.
annals of tropical medicine and public health. 2013; 6(3): 350-352


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Email Alert *
    Add to My List *
* Registration required (free)  

   Case Report
    Article Figures

 Article Access Statistics
    PDF Downloaded262    
    Comments [Add]    
    Cited by others 5    

Recommend this journal