[Study of NK cell activity in patients with oral maxillofacial squamous cell carcinoma]

NK cell activity of peripheral blood lymphocytes against K562 cell line were tested with 125IUdR release assay in 50 normal controls and 50 patients with oral maxillofacial benign tumors and 178 patients with oral maxillofacial squamous cell carcinoma. The data show NK cell activity of patients with primary squamous cell carcinoma is lower than that of normal controls and that of patients with benign tumors (P less than 0.001 and P less than 0.001). NK cell activity of patients with benign tumors is not different from that of normal controls (P greater than 0.05). NK cell activity of patients with II and III grade squamous cell carcinoma is lower than that of patients with I grade squamous cell carcinoma (P less than 0.01). Stage-related NK cell activity is not observed and there is no significant difference between patients with and without lymph-node metastasis. NK cell activity of patients with recurrent squamous cell carcinoma is not only lower than non-recurrent patients and normal controls (P less than 0.001) but also lower than primary squamous cell carcinoma patients (P less than 0.01). The non-recurrent patients have normal NK cell activity. The results indicate that the patients with oral maxillofacial squamous cell carcinoma have impairment of NK cell function. NK cell activity of the patients depresses within one week of operation and returns preoperative level two weeks after operation. Chemotherapy inhibits NK cell activity, which may not return two weeks after chemotherapy. These give reference to clinicians. NK cell activity may be a parameter in monitoring the immunofunction of oral maxillofacial malignant tumor patients.