EXPRESSION OF MCSP AND PRAME IN CONJUNCTIVAL MELANOMA.

Henrike Westekemper (1) , Sara Karimi (1) , Daniela Süsskind (2) , Gerassimos Anastassiou (1) , Michael Freistühler (1) , Daniel Meller (1) , Michael Zeschnigk (3) , Klaus-Peter Steuhl (1) , Norbert Bornfeld (1) , Kurt-Werner Schmid (4) , Florian Grabellus (1)

1 University of Duisburg-Essen, Department of Ophthalmology, Hufelandstr. 55, D-45122 Essen
2 Department of Ophthalmology, Eberhard-Karls University Tübingen, Schleichstr. 12-16, 72076 Tübingen
3 Institute for Humangenetics, University of Duisburg-Essen
4 Institute of Pathology and Neuropathology, University of Duisburg-Essen

Background: To analyse the expression of melanoma chondroitin sulphate proteoglycan (MCSP) and the preferentially expressed antigen of melanoma (PRAME) in conjunctival melanoma (CoM), lymph-node metastases of cutaneous melanoma (LN-met of CM) and conjunctival nevi (CoN) by immunohistology. Methods: Immunohistology was performed in 70 samples of CoM, 25 of LN-met. of CM and 12 of CoN. and assessed by an immuno-reactive-score (0-12 points). Statistical analysis was performed to disclose relevant differences in the expression-pattern. The diagnostic value of the markers was tested by receiver operating characteristics (ROC-analysis). Results: MCSP and PRAME were expressed significantly higher in CoM and LN-metastases of CM than in CoN (p=<0.0001). Within CoM, a MCSP-expression <9.0 points meant higher risk for recurrences (Cox HR=3.1) and a shorter recurrence-free survival (p=0.002) than a MCSP-expression >9.0 points. ROC-analysis showed an area under the curve of 91.3% for MCSP (p=0.0002) and 93.8% for PRAME (p<0.0001). Conclusions: MCSP and PRAME are differentially expressed in conjunctival melanomas and nevi. MCSP might have an impact on the risk for recurrence in being inversely correlated to the event. Both markers have high potential to discriminate CoM from CoN. Our results indicate that immunohistological characteristics gain relevance in the assessment of conjunctival melanoma.

Mots clés: Conjunctiva; Pathology; Neoplasia; Diagnostic tests/Investigation

Henrike Westekemper, Sara Karimi, Daniela Süsskind, Gerassimos Anastassiou, Michael Freistühler, et al.. EXPRESSION OF MCSP AND PRAME IN CONJUNCTIVAL MELANOMA.. British Journal of Ophthalmology, 2010, 94 (10), pp.1322. ⟨10.1136/bjo.2009.167445⟩. ⟨hal-00572624⟩