用固相竞争抑制免疫放射法，体外测定病人血清中乳腺癌相关性抗原ＣＡ２７、２９。结果：乳腺癌病人ＣＡ２７、２９抗原水平明显高于乳腺良性疾病和非乳腺癌恶性肿瘤病人（Ｐ＜０．０１）。阳性率８８．９％，敏感性９０％。１４例乳腺癌术后监测其ＣＡ２７、２９抗原水平，１例肺部有转移者升高，余均较术前下降（Ｐ＜０．０１）。提示ＣＡ２７、２９抗原在乳腺癌的诊断及乳腺癌术后病人的监侧中有一定意义。 The solid-phase competition was used to suppress immunoradioactivity and in vitro serum levels of breast cancer-associated antigen CA27,29 were measured. Results: The levels of CA27 and 29 antigens in breast cancer patients were significantly higher than those in benign and non-malignant breast cancer patients (P<0.01). The positive rate was 88.9% and the sensitivity was 90%. After 14 cases of breast cancer, the levels of CA27 and 29 antigens were monitored. One case of metastases in the lungs was elevated, and the rest was lower than before surgery (P<0.01). This suggests that CA27 and 29 antigens have a certain significance in the diagnosis of breast cancer and the monitoring of breast cancer patients.