Salivary Gland Disorders
Pleomorphic Adenoma
aka PA · Benign Mixed Tumour
Commonest benign salivary gland tumour; slow-growing painless mass composed of epithelial, myoepithelial and mesenchymal-like elements; recurrence risk if incompletely excised or capsule breached.
§ figuresFigures (2)
Fig. 1Micrograph of Pleomorphic Adenoma of Salivary gland. The section shows a cellular area interspersed with islands of lighter stained bluish myxoid tissue. The cellular area is the epithelial element and is composed of cel
“Pleomorphic Adenoma Salivary gland 10x” · Calicut Medical College · CC BY-SA 4.0 · Wikimedia Commons
Fig. 2Micrograph of a pleomorphic adenoma. Pap stain. See also Image:Adenoid cystic carcinoma cytology.jpg
“Pleomorphic adenoma - cytology” · Nephron · CC BY-SA 3.0 · Wikimedia Commons
Verified open-access images only, reproduced for education under their stated licences · no AI-generated or illustrative artwork · Pleomorphic Adenoma figures pending faculty review.
§ overviewOverview
Benign salivary gland neoplasm composed of variable mixtures of epithelial and myoepithelial cells within a chondromyxoid stroma.
§ icdICD Classification
D11
§ etiologyEtiology
- 01PLAG1 or HMGA2 gene rearrangements in most cases
§ epidemiologyEpidemiology
≈60% of all salivary tumours; parotid (85%, especially superficial lobe) > minor glands (palate) > submandibular; F > M, ages 30–50.
§ clinicalClinical Features
- 01Painless, slow-growing, mobile, firm swelling
- 02Parotid: preauricular mass without facial nerve involvement
- 03Palatal: firm submucosal swelling posterolateral hard palate
- 04Long history (years)
§ differentialDifferential Diagnosis
- 01Warthin tumour (bilateral, older males, smokers)
- 02Mucoepidermoid carcinoma
- 03Adenoid cystic carcinoma
- 04Lymph node
- 05Lipoma
§ histopathHistopathology
- 01Biphasic: epithelial (ducts, sheets) + myoepithelial (spindle, plasmacytoid) cells
- 02Chondromyxoid or hyaline stroma
- 03Pseudocapsule with microscopic tumour extensions (pseudopodia)
§ investigationsInvestigations
- 01USG-guided FNAC (85–90% accurate)
- 02MRI (T2 hyperintense with capsule)
- 03Core biopsy avoided in parotid (seeding risk)
§ ihcIHC / Special Stains
- 01Epithelial: CK+; myoepithelial: S-100, GFAP, p63, calponin, SMA
§ treatmentTreatment
- 01Parotid: superficial parotidectomy with facial nerve preservation (deep lobe → total parotidectomy)
- 02Submandibular: gland excision
- 03Palate/minor gland: wide local excision including periosteum/bone
- 04Enucleation → 25–45% recurrence — obsolete
§ complicationsComplications
- 01Recurrence (multinodular)
- 02Facial nerve injury
- 03Frey syndrome (gustatory sweating)
- 04Carcinoma ex pleomorphic adenoma (malignant transformation ≈ 6% in long-standing PA)
§ prognosisPrognosis
Excellent with appropriate surgery; recurrence risk correlates with capsular disruption at first operation.
§ examKey Examination Points
- 01Palpable, mobile, painless mass without facial nerve palsy
- 02Enucleation is inadequate
§ revisionQuick Revision Summary
- 01Commonest salivary tumour · superficial parotidectomy · avoid enucleation · beware carcinoma ex PA
§ vivaBDS Viva Questions
- 01Why not enucleate?
- 02Facial nerve anatomy at parotid surgery?
- 03Signs of malignant transformation?
§ mcqsMCQs — Assessment (3)
Question 1
Commonest site:
Question 2
Recommended operation for parotid PA:
Question 3
Feature suggesting carcinoma ex PA:
§ evidenceReferences & Evidence
Current Classification
WHO Classification of Head and Neck Tumours
5th Edition — Volume 9
WHO Classification of Tumours Editorial Board · 2022
The authoritative international classification of head and neck, odontogenic and salivary gland tumours. Current terminology on this site follows this edition.
Evidence summary
Highest level of evidence linked to this page: WHO / Official Classification.
- L1 · Classification — 3
- L3 · Systematic review — 1
- L6 · Textbook — 3
2 linked sources were published from 2024 onwards. Where guidance is limited or contested, rely on the higher-level sources above rather than this summary. Educational use only — not a substitute for clinical judgement.
Content last reviewed
September 2026
Evidence last reviewed
September 2026
Next scheduled review
September 2027
Review status
EVIDENCE REVIEWED
Search latest PubMed evidence
Last literature search: 7 September 2026
Current Classification
WHO Classification of Tumours Editorial Board. IARC / World Health Organization · 2022
The authoritative international classification of head and neck, odontogenic and salivary gland tumours. Current terminology on this site follows this edition.
Skálová A, Hyrcza MD, Leivo I. Head and neck pathology · 2022 · 16(1):40-53
Summary of changes to salivary gland tumours in the 5th edition WHO classification of head and neck tumours.
IARC / WHO. IARC · 2022
Continuously updated online edition of the WHO head and neck tumour classification.
Systematic Reviews & Meta-Analyses
Salzano G, Scocca V, Troise S et al.. Medical sciences (Basel, Switzerland) · 2025 · 13(3)
Comparative review of extracapsular dissection versus superficial parotidectomy outcomes.
Histopathology References
Barnes L. CRC Press · 2008
Detailed histopathological reference for head and neck diagnostic criteria.
Textbook References
Neville BW, Damm DD, Allen CM et al.. Elsevier · 2024
Standard reference textbook of oral and maxillofacial pathology used throughout this atlas.
Rajendran R, Sivapathasundharam B. Elsevier · 2020
Undergraduate and postgraduate oral pathology textbook widely used in BDS and FCPS curricula.
Additional sources cited on this page
- WHO Head & Neck Tumours 2022
Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.