Sara is a 3 year old girl brought in by Mum for a slowly enlarging brown spot on Conjunctiva of her left eye.

 

 

Differentials of a brown conjunctival spot

  • Conjunctival Naevus
  • Primary Acquired Melanosis
  • Conjunctival Melanoma
  • Ocular melanocytosis
  • Racial Melanosis

Key features on examination of conjunctival melanoma  (source)

  • Elevated
  • Well defined
  • Age 50-60

Key features on examination of conjunctival naevus  (source)

  • Elevated
  • Well defined
  • Age 1-10

Key features on examination of primary acquired melanosis  (source)

  • Flat
  • Poorly defined
  • Age: Middle age

 

Differential diagnoses among conjunctival melanocytic lesions (source)

TYPE OF LESION LOCATION AGE OF ONSET MORPHOLOGY PROGRESSION
Nevus Epithelial conjunctiva, unilateral First to second decade Well-defined, elevated 1% progression to conjunctival melanoma
Racial melanosis Epithelial conjunctiva, bilateral Congenital Poorly defined, flat Rare progression to conjunctival melanoma
PAM Epithelial conjunctiva, unilateral Middle age Poorly defined, flat If atypical, 50% progression to conjunctival melanoma
Ocular melanocytosis Sclera, unilateral Congenital Poorly defined, flat 1% progression to uveal melanoma
Melanoma Stromal conjunctiva, unilateral Sixth to seventh decade Well-defined, elevated Prognosis differs depending on extent

 

 

 

 

 

More reading/ references

  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3192085/
  • https://www.aao.org/bcscsnippetdetail.aspx?id=2422bfaa-bf0b-451c-94de-c0608a0b05cf

 

  • 1. Shields CL, Shields JA. Tumors of the conjunctiva and cornea. Surv Ophthalmol. 2004;49(1):3–24.[PubMed]
  • 2. Shields CL, Fasiuddin AF, Mashayekhi A, Shields JA. Conjunctival nevi: clinical features and natural course in 410 consecutive patients. Arch Ophthalmol. 2004;122(2):167–75. Erratum in: Arch Ophthalmol2006;124(2):198. [PubMed]
  • 3. Gerner N, Nørregaard JC, Jensen OA, Prause JU. Conjunctival naevi in Denmark 1960–1980. A 21-year follow-up study. Acta Ophthalmol Scand. 1996;74(4):334–7. [PubMed]
  • 4. Kurli M, Finger PT. Melanocytic conjunctival tumors. Ophthalmol Clin North Am. 2005;18(1):15–24. vii. [PubMed]
  • 5. Folberg R, McLean IW, Zimmerman LE. Malignant melanoma of the conjunctiva. Hum Pathol. 1985;16(2):136–43. [PubMed]