Purpose: Carcinoembryonic antigen cell adhesion molecule (CEACAM)-1 is a multi-functional protein, with strong predictive value for poor prognosis when found in primary cutaneous melanoma lesions. In this study, the expression of CEACAM1 in uveal melanoma was correlated with clinicopathologic parameters.
Methods: CEACAM1 expression was immunohistochemically evaluated in 79 primary uveal melanomas and 21 liver metastases of patients who were treated at the Hadassah-Hebrew University Medical Center between the years 1986 and 2006. The findings were correlated with location, cell type, extracellular matrix patterns, tumor size, and metastatic disease.
Results: CEACAM1 was expressed in 45% of the primary tumors compared with 81% of the metastases (Fisher's exact test, P = 0.003). There was no significant association between CEACAM1 and location of the primary tumors. Histologically, CEACAM1 was associated with epithelioid-type tumors (69.6%), but not with spindle-type tumors (25.0%) (Cramer's V = 0.354; P = 0.019). Also it was significantly associated with network extracellular matrix pattern (73.3%), but not with silent pattern (11.8%) (Cramer's V = 0.510; P = 0.004). CEACAM1-positive tumors were not statistically different in size from CEACAM1-negative tumors. The higher frequency of CEACAM1 in patients who ultimately developed metastases (58.8% vs. 41.7%) was not statistically significant (likelihood ratio χ(2) = 2.069; P = 0.1503).
Conclusions: This report describes CEACAM1 expression in uveal melanoma. Correlation with poor prognostic factors such as epithelioid cell type and networks of extracellular matrix pattern was found, but definitive prognostic conclusions still cannot be deduced. Additional validation studies on the use of CEACAM1 expression as a prognostic marker are warranted.