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Updated: Jun 2, 2026
05:46
Implantation and Evaluation of Melanoma in the Murine Choroid via Optical Coherence Tomography
Published on: December 2, 2022
KIT mutations in ocular melanoma: frequency and anatomic distribution.
Michelle L Wallander1, Lester J Layfield, Lyska L Emerson
1ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA.
Summary
KIT and PDGFRA mutations occur in 11% of ocular melanomas, similar to other types. CD117 status doesn't predict mutations, so all ocular melanomas need testing for targeted therapy eligibility.
Area of Science:
- Ophthalmology
- Oncology
- Genetics
Background:
- Activating KIT or PDGFRA mutations in melanomas may respond to tyrosine kinase inhibitors.
- KIT mutations are common in cutaneous, mucosal, and acral melanomas but rare in ocular melanoma.
- PDGFRA mutations in ocular melanoma are largely unknown.
Purpose of the Study:
- To investigate the frequency and distribution of KIT and PDGFRA mutations in various ocular melanoma subtypes.
- To correlate mutation status with anatomical site and CD117 (KIT) immunohistochemistry.
- To assess the potential for targeted therapy in ocular melanoma.
Main Methods:
- Analysis of 75 ocular melanomas (choroidal, iris, ciliary body, conjunctival).
- High-resolution melting curve analysis and sequencing for KIT and PDGFRA gene mutations.
- Correlation with anatomical site and KIT (CD117) immunohistochemistry.
Main Results:
- KIT or PDGFRA mutations were found in 8 of 75 (11%) ocular melanomas.
- Mutations were identified in choroidal (9%), iris (33%), and ciliary body (9%) melanomas; none in conjunctival.
- CD117 positivity did not reliably predict KIT mutational status.
Conclusions:
- KIT and PDGFRA mutations are present in ocular melanomas at a significant frequency.
- Mutation analysis is crucial for all ocular melanomas to identify potential candidates for imatinib therapy.
- CD117 immunohistochemistry is insufficient for predicting mutational status.
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