目的：探讨血清凝集肿瘤细胞活性与肿瘤转移的相关性及其对恶性肿瘤临床诊断的意义。方法：采用体外细胞凝集实验，通过计算肿瘤细胞凝集率测定血清活性。结果：正常人、良性肿瘤患者、早期及中晚期恶性实体瘤患者的血清均诱导人鼻咽癌细胞凝集，凝集率分别为３５２％±９５％、３８１％±１１２％、５０７％±１１６％及７２３％±１０４％；血清此活性在恶性肿瘤诊断上的灵敏度为９０６％，特异性为９２１％，准确性为９１３％。结论：血清凝集肿瘤细胞活性与肿瘤转移呈正相关，其可能是一新的广谱恶性肿瘤标志，在恶性肿瘤的临床诊断及预后上具有重要应用价值。 Objective: To investigate the correlation between serum agglutination activity of tumor cells and tumor metastasis and its significance in the diagnosis of malignant tumors. Methods: In vitro cell agglutination assays were used to determine serum activity by calculating tumor cell agglutination. RESULTS: Normal, benign tumors, and serum of patients with early-stage and advanced malignant solid tumors all induced agglutination of human nasopharyngeal carcinoma cells. The agglutination rates were 352%±95% and 381%±112, respectively. %, 507%±116%, and 723%±104%; serum activity was 90. 3%. Conclusion: The activity of serum agglutination tumor cells is positively correlated with tumor metastasis. It may be a new marker of a broad spectrum of malignant tumors. It has important application value in the clinical diagnosis and prognosis of malignant tumors.