Immunophenotype of conjunctival melanomas: comparisons with uveal and cutaneous melanomas.
OBJECTIVE
To characterize the immunophenotypic expression pattern of conjunctival melanomas, with the use of standard melanoma markers as well as microphthalmia transcription factor and p75 neurotrophin receptor.


METHODS
Eleven conjunctival melanomas, including 1 caruncular melanoma, were immunolabeled with a panel of antibodies that included S100, tyrosinase, melan-A, HMB-45 and HMB-50 combination, microphthalmia transcription factor, and p75 neurotrophin receptor. The results were tabulated on the basis of intensity and pervasiveness of labeling and compared with a previous study of uveal melanomas.


RESULTS
Immunolabeling with S100 was at significantly higher levels in conjunctival melanomas than in uveal melanomas. Tyrosinase, HMB-45 and HMB-50 combination, melan-A, and microphthalmia transcription factor were expressed at high levels in conjunctival melanomas, whereas p75 neurotrophin receptor was not expressed.


CONCLUSIONS
Melanomas of the conjunctiva, including the caruncle, expressed S100, tyrosinase, melan-A, HMB-45 and HMB-50 combination, and microphthalmia transcription factor at high levels, suggesting that these are good markers for this melanoma subtype. Expression of S100 was significantly higher in conjunctival melanomas than in uveal melanomas. The immunophenotypic pattern of conjunctival melanomas is most similar to the epithelioid subtype of cutaneous melanomas.
Iwamoto
Satori
S
Division of Dermatology, Department of Medicine, University of Washington Medical Center, Box 356524, Seattle, WA 98195-6524, USA. siwamoto@u.washington.edu
Burrows
Robert C
RC
Grossniklaus
Hans E
HE
Orcutt
James
J
Kalina
Robert E
RE
Boehm
Michael
M
Bothwell
Mark A
MA
Schmidt
Rodney
R
D014408:Biomarkers, Tumor / Q000032:analysis; D003230:Conjunctival Neoplasms / Q000737:chemistry / Q000473:pathology*; D006801:Humans; D007124:Immunoenzyme Techniques; D016130:Immunophenotyping; D008545:Melanoma / Q000737:chemistry / Q000473:pathology*; D009363:Neoplasm Proteins / Q000032:analysis; D012878:Skin Neoplasms / Q000737:chemistry / Q000473:pathology*; D014604:Uveal Neoplasms / Q000737:chemistry / Q000473:pathology*
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins