LRRC4 and serous cystadenoma: We next examined LRRC4 expression in 8 serous cystoma, 30 primary HGSC, and 19 omental metastasis samples by using immunochemistry (IHC), verifying that LRRC4 was significantly down-regulated in primary HGSC (p < 0.05) and omental metastasis samples (p < 0.01) compared with serous cystoma samples.