CP and cystadenoma: The tissue microarray was prepared in the laboratory of Zhejiang Cancer Hospital, which consisted of 91 samples, including five patient groups: 36 samples of primary CP‐s (CP‐sp), 18 primary CP‐i (CP‐ip), 13 secondary CP‐s (CP‐ss), 15 secondary CP‐i (CP‐is), and 9 benign masses (cystadenoma).