Many people have small, stable pigmented iris lesions that never cause trouble. However, some iris naevi enlarge over time and a proportion behave like iris melanoma, so clinicians look for warning signs rather than relying on reassurance. ¹
A widely used ocular-oncology mnemonic is the ABCDEF guide for features associated with higher risk of growth: ¹
- Age young (≤40 years)
- Blood (spontaneous hyphema)
- Clock hour inferior location (typically 4 to 9 o’clock)
- Diffuse configuration (spreading across the iris)
- Ectropion uveae
- Feathery margins
Other concerning clinical signs include new tumour vessels, seeding, angle involvement, a new nodule, pupil distortion, raised intraocular pressure, or documented enlargement on serial photographs. ² ³
Practical advice: if an iris lesion is changing, associated with bleeding, or distorting iris architecture, it deserves prompt specialist review and photo-documentation (often with gonioscopy and anterior-segment imaging where appropriate). ¹
References
- Shields CL, Kaliki S, Hutchinson A, Nickerson S, Patel J, Kancherla S, et al. Iris nevus growth into melanoma: analysis of 1611 consecutive eyes: the ABCDEF guide. Ophthalmology. 2013;120(4):766-772. doi:10.1016/j.ophtha.2012.09.042. PMID: 23290981.
- Shields CL, Dalvin LA, Ancona-Lezama D, Yu MD, Di Nicola M, Williams BK Jr, et al. Review of cystic and solid tumors of the iris. Indian Journal of Ophthalmology. 2019;67(12):1941-1954. doi:10.4103/ijo.IJO_1312_19. PMID: 31755415.
- Shields CL, Shields JA. Iris melanoma: management and prognosis. Saudi Journal of Ophthalmology. 2012;26(2):137-142. doi:10.1016/j.sjopt.2012.02.002. PMID: 23961012.
Related Topics
- When Does a “Freckle” in the Eye Become Concerning?
- What Does a “Freckle in the Eye” Actually Mean? Choroidal, Iris and Conjunctival Naevi Explained
- Choroidal Naevus vs Choroidal Melanoma: Understanding TFSOM-DIM Risk Factors
- How Often Should a Choroidal Naevus Be Checked? Follow-Up Intervals and Imaging Plans
- Iris “Freckles”: Using the ABCDEF Guide to Spot Higher-Risk Iris Naevi
- Conjunctival “Freckles” on the White of the Eye: When a Naevus Is Usually Harmless
- Primary Acquired Melanosis (PAM): Why Some Flat Conjunctival Pigment Needs Oncology Input
- Eye Freckle Symptoms You Shouldn’t Ignore: Blurred Vision, Distortion, Hyphema and Pain
- Multimodal Imaging for Eye Freckles: Optical Coherence Tomography, Autofluorescence, Ultrasound and Photography
- MOLES and TFSOM-DIM: How Specialists Score Choroidal Naevi and Decide on Referral
- Growth Without Transformation: When a Choroidal Naevus Gets Bigger but Isn’t Melanoma
- High-Risk Features in Conjunctival Pigmented Lesions: PAM, Forniceal Location and Feeder Vessels
- Eye Freckles in Young Patients: Special Considerations for Iris and Choroidal Naevi Under 40
- Monitoring an Eye Freckle Safely: Why Baseline Photos and Structured Recall Matter
- When Does an Eye Freckle Need Biopsy or Treatment Instead of Observation?
- Living With an Eye Freckle: Cancer Risk, Prognosis and When to Seek a Second Opinion
- Eye Freckle Assessment at Blue Fin Vision®: Photography and Optical Coherence Tomography
- B-scan Ultrasound for Eye Freckles: Measuring Thickness and Looking for Melanoma Features
- Monitoring a Choroidal Naevus at Blue Fin Vision®: Structured Imaging, Written Plans and When We Refer
- Second Opinion on a ‘Suspicious’ Eye Freckle: Differentiating Naevus from Choroidal Melanoma
- Linked Care With Ocular Oncology: Fast Referral and Follow-Up if Melanoma Is Suspected
