目的: 评估CA9在预测透明细胞肾细胞癌（clear cell renal cell carcinoma, ccRCC）患者术后复发或转移以及生存预后中的价值。方法: 回顾分析上海交通大学医学院附属瑞金医院2017年1月1日至2020年12月31日期间收治的231例ccRCC患者，所有患者均接受了肾癌根治或部分切除术，分析其临床病理资料，并对患者进行随访，统计其肿瘤复发、转移和总生存期（overall survival, OS）、无病生存期(disease-free survival, DFS)情况。收集所有肿瘤组织切片及蜡块，制作组织微阵列，使用CA9多克隆抗体对组织微阵列进行免疫组织化学分析。采用Kaplan-Meier和多元Cox回归模型分析，评估组织微阵列CA9表达水平与患者临床病理特征及OS、DFS间的相关性。结果: 231例ccRCC患者的中位随访时间为37个月(13~54个月)，有8例患者死亡，38例（16.5%）患者术后出现肿瘤复发和（或）转移，其中3例出现肿瘤复发，29例发生肿瘤转移，另6例患者同时出现肿瘤复发和肿瘤转移。231例患者中，CA9的阳性表达率为94%(217/231)，其中153例(66%) CA9染色率≥85%，78例（34%)CA9染色率<85%。卡方分析显示，CA9的表达不仅与肿瘤T分期、国际泌尿病理学会（International Society of Urological Pathology，ISUP）核分级、肉瘤样或横纹肌样分化（坏死）、被膜侵犯、血管浸润等组织病理学参数相关（P均<0.01），且与肿瘤复发、转移及患者生存状态相关（P均<0.01），但与年龄、性别及肿瘤发生部位无关（P均>0.05）。卡方分析表明，CA9（<85%）低表达是ccRCC患者术后OS、DFS不良的预测因素，危险比分别为6.211(P=0.002)和8.980（P<0.001）。结论: ccRCC组织中CA9低表达与低OS、DFS相关，是ccRCC患者术后短OS和短DFS的独立危险因素，可作为评估ccRCC患者预后的分子标志物。

Objective: To evaluate the prognostic value of CA9 in predicting postoperative recurrence， metastasis or survival in patients with clear cell renal cell carcinoma(ccRCC). Methods: The clinical pathological data from 231 patients with ccRCC who underwent radical or partial nephrectomy from January 1, 2017 to December 31, 2020 in Ruijin Hospital,Shanghai Jiao Tong University were retrospectively analyzed. The patients were followed up for the overall survival (OS),disease-free survival (DFS),and tumor recurrence or metastasis. All pathological sections and wax blocks of tumor issue were collected to make tissue microarray, and immunohistochemical analysis of tissue microarray was performed using CA9 polyclonal antibody. SPSS statistical software multivariate Cox and Kaplan-Meier were used to evaluate the correlation of CA9 expression with clinicopathological features, OS and DFS. Results: Of the 231 ccRCC patients had a median follow-up of 37 months (13-54 months). It revealed that postoperative recurrence and/or metastasis occurred in 38 cases, inclu-ding 6 cases with both recurrence and metastasis, 3 cases with only recurrence, 29 cases with only metastasis, and 8 deaths. Among 231 patients, CA9 positive expression rate was 94%(217/231), of which 153 (66%) were with cells stained with CA9 ≥85% and 78 (34%) were stained with CA9 <85%. Chi-square analysis showed that the expression of CA9 was not only correlated with T stage, ISUP nuclear grade, sarcomatoid or rhabdomyoid differentiation, necrosis, capsule invasion, vascular infiltration, but also correlated with tumor recurrence, metastasis and survival status. There was no relationship between CA9 expression and age, sex and tumor location (P>0.05). Univariate Kaplan-Meier analysis and multiva-riate Cox analysis showed that low expression of CA9 (<85%) was a poor prognostic factor for postoperative overall survival (OS) and disease-free survival (DFS) in patients with ccRCC, with hazard ratios of 6.211 (P=0.002) and 8.980 (P<0.001), respectively. Conclusions: In ccRCC, low expression of CA9 is associated with poor OS and DFS, and is an independent risk factor for OS and DFS in postoperative patients with ccRCC, which may serve as a useful prognostic indicator.