Soft Tissue Lesions
Mucocele
aka Mucous Extravasation Cyst · Mucous Retention Cyst
Dome-shaped, fluctuant swelling from extravasation or retention of saliva in minor salivary glands, most common on lower lip.
§ figuresFigures (3)
Fig. 1Surgical removal of a mucocele in the lower lip.
“Surgical removal of a Mucocele.” · Jeffrey Dorfman · 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 · Mucocele figures pending faculty review.
§ overviewOverview
Cystic or pseudocystic accumulation of mucin following rupture of a salivary duct (extravasation) or obstruction (retention).
§ icdICD Classification
K11.6
§ etiologyEtiology
- 01Trauma to minor salivary gland duct (extravasation)
- 02Duct obstruction (retention)
§ epidemiologyEpidemiology
Most common salivary gland lesion. Young adults/children. Lower lip (60–70%).
§ pathogenesisPathogenesis
Duct rupture → mucin spillage into connective tissue → granulation tissue wall (extravasation). True retention cyst has epithelial lining.
§ clinicalClinical Features
- 01Painless, dome-shaped, bluish-translucent swelling
- 02Fluctuant
- 03History of trauma/lip biting
- 04May rupture and recur
§ differentialDifferential Diagnosis
- 01Fibroma
- 02Hemangioma
- 03Lipoma
- 04Salivary gland tumour
§ histopathHistopathology
- 01Extravasation: mucin pool surrounded by granulation tissue, no epithelial lining
- 02Retention: mucin-filled cavity with ductal epithelial lining
§ investigationsInvestigations
- 01Clinical diagnosis; excisional biopsy confirms
§ treatmentTreatment
- 01Excision with associated minor salivary gland
- 02Marsupialization (ranula)
§ complicationsComplications
- 01Recurrence if gland not removed
§ prognosisPrognosis
Excellent with complete excision.
§ examKey Examination Points
- 01Extravasation type lacks epithelial lining
- 02Lower lip most common site
- 03Remove gland to prevent recurrence
§ revisionQuick Revision Summary
- 01Bluish fluctuant lower lip swelling
- 02Extravasation = pseudocyst
- 03Excise with gland
§ vivaBDS Viva Questions
- 01Differentiate extravasation from retention mucocele.
- 02What is the treatment?
- 03Why does it recur?
§ mcqsMCQs — Assessment (3)
Question 1
Most common site for mucocele:
Question 2
Extravasation mucocele is:
Question 3
To prevent recurrence, remove:
§ evidenceReferences & Evidence
Current Classification
WHO Classification of Tumours Online — Head and Neck
IARC / WHO · 2022
Continuously updated online edition of the WHO head and neck tumour classification.
Evidence summary
Highest level of evidence linked to this page: WHO / Official Classification.
- L1 · Classification — 1
- L6 · Textbook — 3
1 linked source was 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
IARC / WHO. IARC · 2022
Continuously updated online edition of the WHO head and neck tumour classification.
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
- Neville BW. Oral & Maxillofacial Pathology, 4e
Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.