Cadherin expression in ovarian carcinoma and malignant mesothelioma cell effusions

OBJECTIVE: To analyze potential differences in cadherin expression between ovarian carcinoma/primary peritoneal carcinoma (OC/PPC) and malignant mesothelioma (MM) at this anatomic site. STUDY DESIGN: MM (N=24) and OC/PPC (N= 53) effusions were analyzed for E-cadherin, N-cadherin and P-cadherin protein expression using immunocytochemistry. RESULTS: Both MM and OC/PPC cells showed frequent expression of all 3 cadherins. OC/PPC specimens expressed E-cadherin and N-cadherin in 52 of 53 cases and P-cadherin in 51 of 53 cases. MM effusions expressed E-cadherin, N-cadherin and P-cadherin in 22 of 24, 21 of24 and 23 of24 cases, respectively. The differences in the percentage of cadherin-positive cells was weakly significant for P-cadherin (higher expression in MM, p = 0.04), but E-cadherin and N-cadherin expression was comparable (p > 0.05). CONCLUSION: MM and OC/PPC coexpress different cadherin family members. P-cadherin, E-cadherin and N-cadherin are not useful for differentiation between OC/PPC and MM in effusions.