Clinical Presentation and Diagnosis
- Solitary tumor
- Slow growing
- Painless
- Firm single nodular mass
- Can cause atrophy of mandibular ramus
- Highly variable histology
- Biphasic with epithelial and myoepithelial elements
- Mucoid, myxoid, cartilaginous, or hyaline stroma
- Squamous metaplasia and epithelial pearls may be present
- Surrounding fibrous pseudocapsule
- Tissue sampling procedures: fine needle aspiration (FNA) and core needle biopsy
- Diagnostic imaging techniques: ultrasound, CT scan, and MRI
- FNA can determine malignancy with 90% sensitivity
- Core needle biopsy allows more accurate histological typing
- Ultrasound can determine and characterize superficial parotid tumors

Treatment
- Surgical resection is the mainstay of treatment
- Needle biopsy is recommended to confirm diagnosis
- Surgical technique and adjuvant radiotherapy depend on malignancy
- Surgical treatment of parotid gland tumors is challenging
- Different surgical techniques available based on tumor size, location, and mobility

Prognosis
- Pleomorphic adenomas can recur after a long time
- Recurrence rate increases with time
- Evaluation of different surgical techniques is important for future results
- Detection of early stages is crucial for prognosis
- Morbidity and aesthetic outcomes should be considered

Related Concepts
- Warthins tumor - monomorphic adenoma
- Carcinoma
- Sialadenitis

References (selected)
- Bin Xu, M.D., Ph.D. Pleomorphic adenoma. Pathology Outlines
- Cohen EG, Patel SG, Lin O, Boyle JO, Kraus DH, Singh B, et al. (June 2004). Fine-needle aspiration biopsy of salivary gland lesions in a selected patient population. Archives of Otolaryngology–Head & Neck Surgery. 130 (6): 773–778.
- Batsakis JG, Sneige N, el-Naggar AK (February 1992). Fine-needle aspiration of salivary glands: its utility and tissue effects. The Annals of Otology, Rhinology, and Laryngology. 101 (2 Pt 1): 185–188.
- Wan YL, Chan SC, Chen YL, Cheung YC, Lui KW, Wong HF, et al. (October 2004). Ultrasonography-guided core-needle biopsy of parotid gland masses. AJNR. American Journal of Neuroradiology. 25 (9): 1608–1612.
- Białek EJ, Jakubowski W, Karpińska G (September 2003). Role of ultrasonography in diagnosis and differentiation of pleomorphic adenomas: work in progress. Archives of Otolaryngology–Head & Neck Surgery. 129 (9): 929–933.
- Steve C Lee, MD, PhD. Salivary Gland Neoplasms. Medscape
- Psychogios G, Bohr C, Constantinidis J, Canis M, Vander Poorten V, Plzak J, et al. (January 2021). Review of surgical techniques and guide for decision making in the treatment of benign parotid tumors (PDF). European Archives of Oto-Rhino-Laryngology. 278 (1): 15–29.
- Schapher M, Koch M, Agaimy A, Goncalves M, Mantsopoulos K, Iro H (September 2019). Parotid pleomorphic adenomas: Factors influencing surgical techniques, morbidity, and long-term outcome relative to the new ESGS classification in a retrospective study. Journal of Cranio-Maxillo-Facial Surgery. 47 (9): 1356–1362.
- Silvoniemi A, Pulkkinen J, Grénman R (November 2010). Parotidectomy in the treatment of pleomorphic adenoma -- analysis of long-term results. Acta Oto-Laryngologica. 130 (11): 1300–1305.
- Alexandru Bucur; Octavian Dincă; Tiberiu Niță; Cosmin Totan; Cristian Vlădan (March 2011). Parotid tumors: our experience. Rev. chir. oro-maxilo-fac. implantol. (in Romanian). 2 (1): 7–9.
- Patey DH, Thackray AC (March 1958). The treatment of parotid tumours in the light of a pathological study of parotidectomy material. The British Journal of Surgery. 45 (193): 477–487.
- Mantsopoulos K, Koch M, Klintworth N, Zenk J, Iro H (January 2015). Evolution and changing trends in surgery for benign parotid tumors. The Laryngoscope. 125 (1): 122–127.
- Britt CJ, Stein AP, Gessert T, Pflum Z, Saha S, Hartig GK (February 2017). Eisele DW (ed.). Factors influencing sialocele or salivary fistula formation postparotidectomy. Head & Neck. 39 (2): 387–391.
- McGurk M, Thomas BL, Renehan AG (November 2003). Extracapsular dissection for clinically benign parotid lumps: reduced morbidity without oncological compromise. British Journal of Cancer. 89 (9): 1610–1613.
- Leonetti JP, Marzo SJ, Petruzzelli GJ, Herr B (September 2005). Recurrent pleomorphic adenoma of the parotid gland. Otolaryngology–Head and Neck

Pleomorphic adenoma (Wikipedia)

Pleomorphic adenoma (or benign mixed tumor) is a common benign salivary gland neoplasm characterised by neoplastic proliferation of epithelial (ductal) cells along with myoepithelial components, having a malignant potentiality. It is the most common type of salivary gland tumor and the most common tumor of the parotid gland. It derives its name from the architectural Pleomorphism (variable appearance) seen by light microscopy. It is also known as "Mixed tumor, salivary gland type", which refers to its dual origin from epithelial and myoepithelial elements as opposed to its pleomorphic appearance.

Pleomorphic adenoma
Other names	Benign mixed tumor
Cytopathology of pleomorphic adenoma (Pap stain). It can usually be diagnosed by its typical fibrillary stroma (mesenchyme). Stromal cell nuclei are small. Myoepithelial cells are usually the predominant cell type, and their nuclei can have various shapes but are usually more elongated than in epithelial cells. Epithelial cell nuclei may have prominent nucleoli.
Specialty	Oncology