AtlasPremalignantActinic Cheilitis

Premalignant Disorders

Actinic Cheilitis

aka Solar Cheilitis · Actinic Cheilosis

Chronic UV-induced degeneration of the vermilion of the lower lip; a potentially malignant disorder that may progress to lip SCC.

Cause
Chronic UV-B
Site
Lower lip vermilion
Risk
SCC transformation 10–20%
Rx
Photoprotection · 5-FU · vermilionectomy

§ overviewOverview

Premalignant degeneration of the lip vermilion caused by cumulative ultraviolet radiation exposure.

§ icdICD Classification

L57.0

§ etiologyEtiology

  • 01Chronic UV-B exposure
  • 02Fair skin (Fitzpatrick I–II)
  • 03Outdoor occupation
  • 04Tobacco cofactor

§ riskRisk Factors

  • 01Age >40
  • 02Male
  • 03Outdoor work (farmer, sailor, fisherman)
  • 04Lack of lip photoprotection
  • 05Immunosuppression

§ epidemiologyEpidemiology

Common in tropical and rural populations; M:F ≈ 10:1; >90% involve the lower lip.

§ pathogenesisPathogenesis

UV-B induces TP53 mutations and epithelial dysplasia in lip keratinocytes with solar elastosis of the underlying connective tissue.

§ clinicalClinical Features

  • 01Dry, scaly, atrophic lower lip
  • 02Loss of vermilion border definition
  • 03Pale/white patches with red erosions
  • 04Persistent crusting/fissuring
  • 05Focal ulcer or induration = suspect SCC

§ differentialDifferential Diagnosis

  • 01Cheilitis (contact/exfoliative)
  • 02Lupus erythematosus
  • 03Lip SCC
  • 04Leukoplakia of lip

§ histopathHistopathology

  • 01Epithelial atrophy or hyperkeratosis
  • 02Variable dysplasia
  • 03Basophilic degeneration of collagen (solar elastosis)
  • 04Perivascular chronic inflammation

§ investigationsInvestigations

  • 01Incisional biopsy of indurated/ulcerated area
  • 02Dermoscopy of lip
  • 03Toluidine-blue staining as adjunct

§ treatmentTreatment

  • 01Photoprotection: SPF 30+ lip balm, wide-brim hat
  • 02Topical 5-FU, imiquimod, or diclofenac for field change
  • 03Cryotherapy for focal lesions
  • 04CO₂ laser vaporisation or vermilionectomy (lip shave) for severe/dysplastic disease

§ complicationsComplications

  • 01Progression to lip SCC (up to 10–20%)
  • 02Cosmetic deformity after vermilionectomy

§ prognosisPrognosis

Excellent with photoprotection; malignant transformation risk mandates biopsy of any indurated or non-healing area.

§ examKey Examination Points

  • 01Loss of vermilion demarcation
  • 02Palpate for induration
  • 03Photograph and map lesion

§ revisionQuick Revision Summary

  • 01UV-induced PMD of lower lip
  • 02Solar elastosis on histology
  • 03Vermilionectomy for high-grade dysplasia

§ vivaBDS Viva Questions

  • 01How does actinic cheilitis differ from cheilitis?
  • 02What are the indications for vermilionectomy?
  • 03Rate of malignant transformation?

§ mcqsMCQs — Assessment (3)

Question 1

Most common site of actinic cheilitis:

Question 2

Definitive treatment for widespread dysplastic actinic cheilitis:

Question 3

Hallmark histological feature:

References

  1. Neville BW. Oral & Maxillofacial Pathology, 4e
  2. Warnakulasuriya S. Oral Oncol 2020

Draft — pending faculty review. Educational use only; verify against current guidelines and primary sources before clinical application.