Pleomorphic adenoma is a benign, slow-growing neoplasm that most commonly affects the parotid gland. It has epithelial, myoepithelial, and stromal components. The prognosis is generally good after the surgical removal, however, there is an increased incidence of recurrence particularly if the parotid gland is affected.
Pleomorphic adenoma (PA) is the most common type of benign tumor of the salivary gland   .
Pleomorphic adenoma or benign mixed tumor, occur most frequently (85%) in the parotid glands , followed by the minor salivary glands in 10% of the cases, and then by the submandibular glands at 5% . The adenoma presents as a small, mobile, slowly growing, painless mass of 2-6 cm; however, occasionally much larger tumors have been encountered . Patients have varying symptoms, which may depend on the location of the tumor, and may include hoarseness of voice, dyspnea, and difficulty in chewing and eating.
The tumors occur most frequently in middle-aged women. They originate in most cases from the superficial lobe of the parotid gland and present as a swelling of the gland below the ear; however, they can develop in the deep lobe of the parotid gland, where they will not be easily noticed in early stages . Tumors of the deep lobe of the parotid gland, and of the minor salivary glands sometimes appear in the parapharyngeal space . More common locations for adenomas of the minor salivary glands are the hard and soft palate, and the mucosa of the lip . Most tumors are solitary, but bilateral tumors have also been found . The facial nerve is rarely involved.
The adenomas are often encapsulated. The histological pattern varies case by case [3[. All tumors are mixtures of epithelial cells, myoepithelial and basal cells, with varying contributions from stroma; using the relative amounts of different cell types and stroma for predicting future outcomes has not yet met with success .
Although PA is a benign tumor, it can become malignant. Surgical removal of the tumor by enucleation –or preferably by parotidectomy at the first incidence - is the cornerstone of treatment. Surgery has to be done carefully to preserve the facial nerve and to avoid rupture, which could lead to recurrence of the tumor.
Pleomorphic adenomas of the lacrimal glands (PALG) constitute about a tenth of the lacrimal gland tumors. Patients with PALG present with slowly progressing proptosis. The treatment for PALG is total removal of the tumor .
Jaw & Teeth
- Parotid Mass
A well-defined parotid mass with increased signal intensity on proton density- and T2-weighted images is highly suggestive of the diagnosis. [emedicine.com]
We report a case of a 77-year-old man, who presented with a 6-year history of a parotid mass that had undergone rapid growth within weeks. [ncbi.nlm.nih.gov]
- Mouth Breathing
CASE REPORT A 32-year-old woman experienced snoring and mouth-breathing during sleep. [ncbi.nlm.nih.gov]
- Lip Swelling
A 37 year old female Nigerian house wife was seen with a four year history of painless slowly progressive upper lip swelling. Prior to her presentation, she had surgery for same swelling in a peripheral hospital. [ncbi.nlm.nih.gov]
- Joint Stiffness
Characteristics include red or dark patches on the skin; burning, itching, swelling, hardening, and tightening of the skin; yellow spots on the whites of the eyes; joint stiffness with trouble moving or straightening the arms, hands, legs, or feet; pain [emedicine.com]
- Small Hand
We present a very rare case of a metastasising pleomorphic adenoma with spinal cord compression and review the small handful of cases with central nervous system (CNS) involvement in the literature. [ncbi.nlm.nih.gov]
- Periorbital Fullness
A 53-year-old woman presented with a 1-month history of decreased vision and progressive left periorbital fullness. Exam and radiography confirmed a left lacrimal gland mass causing mass effect on the globe and a compressive optic neuropathy. [ncbi.nlm.nih.gov]
- Bilateral Proptosis
A Chinese woman (48 years old) with hyperthyroidism showed a gradually growing mass in the lateral region of the left upper eyelid that was present for 4 years and bilateral proptosis for 5 years. [ncbi.nlm.nih.gov]
- Blurred Vision
A 57-year-old man was admitted for left-sided blurred vision, left-sided weakness, dysarthria, lightheadedness, and syncope. [ncbi.nlm.nih.gov]
Face, Head & Neck
- Neck Mass
Evaluating the adult patient with a neck mass. Med Clin North Am 2010;94:1017-29. [ PubMed ] Tsakiropoulou E, Konstantinidis I, Vital I, et al. Ectopic Warthin’s tumour presenting as a neck mass. [gs.amegroups.com]
Neck mass with marked squamous metaplasia: A diagnostic pitfall in aspiration cytology. J Oral Pathol Med 2008;37:56-8. 6. Siddaraju N, Murugan P, Basu D, Verma SK. [ccij-online.org]
The radiological tools for the diagnosis and differentiation of salivary gland disease are computerized tomography (CT) scans, magnetic resonance imaging (MRI), and ultrasonography  . MRI may be the instrument of choice over CT scan, because of its superior definition of soft tissue and tumor margins . Ultrasound may also be used to serve as the first diagnostic tool; it can differentiate malignant lesions from benign ones with very high accuracy (96%), and can successfully predict PA cases . Apart from location, shape, dimensions and margin , ultrasound can distinguish between cystic and solid masses, and between intra- and extracapsular tumors . It can also be used for guiding fine needle biopsy .
Fine needle aspiration biopsy is also an important tool for preoperative diagnosis; it is safe and reliable but its sensitivity is variable and is more accurate for the diagnosis of benign lesions than for malignant ones   .
Because of the diverse histological appearance of PAs, it may not be easy to differentiate them histologically from other neoplasms, such as myoepithelioma or some carcinomas .
- Rai S, Sodhi SP, Sandhu SV. Pleomorphic adenoma of submandibular gland: An uncommon occurrence. Natl J Maxillofac Surg. 2011 Jan;2(1):66-68.
- Jain S, Hasan S, Vyas N, Shah N, Dalal S. Pleomorphic Adenoma of the Parotid Gland: Report of a Case With Review of Literature. Ethiop J Health Sci. 2015 Apr; 25(2): 189–194.
- Di Palma S, Simpson RHW, Skalova A, Leivo I. Major and Minor Salivary Glands. In: Cardesa A, Slootweg PJ, eds. Pathology of the head and neck. Berlin:Springer; 2006:131-170.
- Guerriere CN, Goff BJ, Cummings GH, Auber AE. An unusually large, solid tumor of the parotid gland. Ann Plast Surg. 1999 Nov;43(5):529-532.
- Silva SJ, Costa Junior GT, Brant Filho AC, Faria PR, Loyola AM. Metachronous bilateral pleomorphic adenoma of the parotid gland. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006 Mar;101(3):333-338.
- Hakeem AH, Hazarika B, Pradhan SA, Kannan R. Primary pleomorphic adenoma of minor salivary gland in the parapharyngeal space. World J Surg Oncol. 2009 Nov 12;7:85.
- Pons Vicente O, Almendros Marqués N, Berini Aytés L, Gay Escoda C. Minor salivary gland tumors: A clinicopathological study of 18 cases. Med Oral Patol Oral Cir Bucal. 2008 Sep 1;13(9):E582-588.
- Wittekindt C, Streubel K, Arnold G, Stennert E, Guntinas-Lichius O. Recurrent pleomorphic adenoma of the parotid gland: analysis of 108 consecutive patients. Head Neck. 2007; 29(9):822-828.
- Rose GE, Wright JE. Pleomorphic adenoma of the lacrimal gland. Br J Ophthalmol. 1992 Jul;76(7):395-400.
- Bialek EJ, Jakubowski W, Karpinska G. Role of ultrasonography in diagnosis and differentiation of pleomorphic adenomas. Arch Otolaryngol. Head Neck Surg. 2003;129:929–933.
- Contucci AM, Corina L, Sergi B, Fadda G, Paludetti G. Correlation between fine needle aspiration biopsy and histologic findings in parotid masses. Acta Otorhinolaryngol Ital. 2003 Aug;23(4):314-318.
- Sergi B, Contucci AM, Corina L, Paludetti G. Value of fine-needle aspiration cytology of parotid gland masses. Laryngoscope. 2004 Apr;114(4):789.
- Akhavan-Moghadam J, Afaaghi M, Maleki AR, Saburi A. Fine Needle Aspiration: An Atraumatic Method to Diagnose Head and Neck Masses. Trauma Mon. 2013 Dec; 18(3): 117–121.