Recurrent bluish swelling of the lower lip in a teenager
14-year-old female
§Chief complaint
Painless bubble on the inside of the lower lip that bursts and returns
§Medical & dental history
- 01Healthy
- 02Habit of biting the lower lip
§Clinical examination
- 01Dome-shaped, fluctuant, bluish translucent swelling 9 mm on the lower labial mucosa
- 02Painless, soft, non-pulsatile, no blanching on pressure
- 03History of repeated rupture with clear viscous discharge and recurrence
- 04No other lesions; salivary flow normal
§ 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.
§Differential diagnosis
§Final diagnosis
Mucous extravasation cyst (mucocele) of a lower labial minor salivary gland
Bluish translucent fluctuant swelling of the lower lip in a lip-biting adolescent with a history of rupture and recurrence is a classic extravasation mucocele; excision with the feeding minor gland is both diagnostic and curative.
§Investigations
- 01Clinical diagnosis; excisional biopsy provides confirmation
- 02Ultrasound only if the lesion is deep or atypical
§Treatment plan
- 01Excision of the mucocele together with the associated minor salivary glands
- 02Counselling to stop lip biting to reduce recurrence
§Surgical procedure
- 01Elliptical mucosal incision under local anaesthesia, lesion dissected with the adjacent feeding minor glands
- 02Careful avoidance of adjacent gland trauma; closure with 5-0 resorbable sutures
§Histopathology report
Cystic space without an epithelial lining, containing mucin and foamy macrophages (muciphages), surrounded by granulation tissue and adjacent minor salivary gland with chronic sialadenitis. Mucous extravasation phenomenon.
§Follow-up & outcome
- 011 week — sutures dissolved, healing well
- 023 months — no recurrence
- 0312 months — mucosa normal, habit stopped
Outcome: Cured by excision with no recurrence at one year.
§Discussion
- 01Extravasation mucoceles (lower lip, trauma-related, no epithelial lining) are far more common than retention cysts (older patients, ductal obstruction, epithelial lining).
- 02Recurrence follows incomplete removal of the feeding gland or continued trauma.
- 03A firm persistent swelling of the upper lip should raise suspicion of a salivary neoplasm rather than a mucocele.
§Clinical pearls / learning points
- 01Remove the feeding minor gland, not just the cyst, or it recurs.
- 02Upper lip swelling = think tumour; lower lip = think mucocele.
§Viva questions
Difference between extravasation and retention mucocele?
Extravasation has no epithelial lining and follows duct rupture from trauma; retention is lined by ductal epithelium and follows obstruction.
What is a ranula?
A mucocele of the sublingual gland in the floor of mouth; a plunging ranula extends through mylohyoid into the neck.
§MCQs
Q1The commonest site of a mucocele is:
Q2A mucous extravasation cyst is lined by:
§ 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 et al. Oral and Maxillofacial Pathology, 4th edition.
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