用单克隆抗体Ｈｂ３检测１３２例正常献血员，８４例消化道良性疾病患者及３８８例肿瘤病人血清中的肿瘤抗原ＣＡ－Ｈｂ３，发现其阳性率依次为：正常献血员３．Ｏ％，消化道良性疾病患者７．Ｏ％，结直肠癌病人５５．８％，胃癌及其他癌患者分别４３．Ｏ％和３１．４％。用根治手术切除的病人，其ＣＡ－Ｈｂ３以下降型为主，而呈下降趋势者术后复发率低；用姑息法和未切除的病人则结果相反。表明ＣＡ－Ｈｂ３的术后变化规律与手术种类和复发率有密切关系。 Monoclonal antibody Hb3 was used to detect the tumor antigen CA-Hb3 in 132 cases of normal blood donors, 84 cases of benign gastrointestinal diseases and 388 cases of tumor patients. The positive rate was found to be: normal blood donors. O%, patients with benign diseases of digestive tract 7. O%, 55.8% of colorectal cancer patients, gastric cancer and other cancer patients were 43. O% and 31.4%. In patients undergoing radical resection, the CA-Hb3 was predominantly declining, whereas the descending trend showed a low postoperative recurrence rate. The palliative and unresected patients had opposite results. It shows that the postoperative change of CA-Hb3 is closely related to the type of surgery and the recurrence rate.