The absence of the AGR2 protein was observed differentially expressed in high‐grade serous carcinoma (<0.001), samples with lymphatic vascular invasion (P = .003), bilateral involvement (P = 0.005) necrosis (P = .034), ovarian surface involvement (P = .032), and lymph node metastasis (P = .003). The gene discussed is AGR2; the disease is serous adenocarcinoma.