CA9 and neoplasm: There were 145 males and 49 females; 76 cases were < 60 years old, 118 cases were ≥ 60 years old, with an average age of 62.3 ± 12.2; 105 cases were < T1, 89 were T1; There were 80 cases of high differentiation and 114 cases of poor differentiation; 83 cases of single tumor and 111 cases of multiple tumors; 72 cases of tumor diameter ≥ 3 cm, 122 cases of tumor diameter < 3 cm; 76 cases had at least one recurrence during the 5-year follow-up period, and 118 cases had no recurrence; CA-IX expression was positive in 132 cases and negative in 62 cases.