OBJECTIVE To investigate the relationship between serum LncRNA MALAT1 and miR-204-5p expression and prognosis in patients with supraglottic carcinoma.METHODS From November 2016 to November 2020,118 patients with supraglottic carcinoma who were treated in the Department of Otolaryngology,Baoding First Central Hospital were analyzed,as the observation group,and 118 healthy adults were selected as the control group.The observation group was divided into poor prognosis group(n=20 cases)and good prognosis group(n=98 cases)according to the survival situation.Real-time fluorescence quantitative PCR(qRT-PCR)technology was applied to detect the expression levels of LncRNA MALAT1 and miR-204-5p.Pearson method was applied to analyze the correlation between serum LncRNA MALAT1 and miR-204-5p levels.Receiver operating characteristic(ROC)curves were plotted to analyze the predictive value of serum LncRNA MALAT1 and miR-204-5p levels for the prognosis of patients with supraglottic carcinoma.RESULTS The serum LncRNA MALAT1 level in the observation group was prominently higher than that in the control group(P<0.05),and the miR-204-5p level was prominently lower than that in the control group(P<0.05).The expression level of serum LncRNA MALAT1 was negatively correlated with miR-204-5p(r=-0.487,P<0.001).The levels of serum LncRNA MALAT1 and miR-204-5p were related to T staging,lymph node metastasis,and differentiation degree(P<0.05).The level of serum LncRNA MALAT1 in the poor prognosis group was greatly higher than that in the good prognosis group(P<0.05),while the proportions of T1 stage,no lymph node metastasis,high differentiation,clinical stages Ⅰ-Ⅱ,and the level of serum miR-204-5p were greatly lower than those in the good prognosis group(P<0.05).ROC curve showed that the AUC of LncRNA MALAT1 combined miR-204-5p in predicting the prognosis of supraglottic carcinoma patients was prominently higher than that of LncRNA MALAT1 alone(Z=3.079,P=0.002)and miR-204-5p alone(Z=3.338,P=0.001).CONCLUSION Serum LncRNA MALAT1 level is elevated and serum miR-204-5p level is reduced in patients with supraglottic carcinoma.They have certain value in evaluating the prognosis of patients with supraglottic carcinoma.