Clinical Diagnostic Value Of Fine Needle Aspiration Cytology And Frozen Section In Parotid Gland Tumors

Objective:To explore the clinical diagnostic value of preoperative Fine needle aspiration cytology(FNAC)and intraoperative Frozen section(FS)in parotid gland tumors.Methods:1.There is a retrospective analysis of 389 patients who were determined to have parotid gland tumours by histopathology and underwent surgery at the Affiliated Hospital of Yanbian University from June 2002 to June 2021.Age,sex and histopathological type of these 389 patients were analyzed.2.Taking the postoperative histopathological diagnosis as the gold standard,I evaluated the diagnostic coincidence rate of FNAC and FS and calculated the Sensitivity(SE),Specificity(SP),Positive predictive value(PPV),Negative predictive value(NPV),Youden index(YI),Likelihood ratio(LR).The qualitative diagnostic value of the two methods for parotid gland tumor was compared in the patients who underwent both FNAC and FS.All data were statistically analyzed by SPSS 26.0 software.A P-value of <0.05 was considered statistically significant.Results:1.Among 389 patients with parotid gland tumors,335 patients(86.1%)suffered from benign tumors and 54 patients(13.9%)suffered from malignant tumors.Among the patients with benign tumors,there were 209 of them(62.4%)developing pleomorphic adenoma,107(31.9%)of them developing Warthin tumor,and 19patients(5.7%)developing other benign tumors.Among the cases with malignant tumors,there were 11 cases of adenoid cystic carcinoma,8 cases of mucoepidermoid carcinoma,8 cases of acinic cell carcinoma,8 cases of squamous cell carcinoma,6cases of pleomorphic adenocarcinoma,6 cases of malignant lymphoma,7 cases of other malignant tumors.The male to female ratio of patients with parotid gland tumors was 1.26:1(217/172 cases),and the male to female ratio of patients with Warthin tumors was 10.9:1(98/9 cases).It also can be seen that the mean age of patients with benign tumor was 50.9,and that of patients with malignant tumor was56.3.In addition,the mean age of onset of malignant tumor was higher than that of patients with benign tumor(P=0.011).2.Compared between preoperative FNAC diagnosis and postoperative histopathological diagnosis of 340 patients,it showed that the coincidence rate of definite diagnosis was 66.5% and of qualitative diagnosis was 92.6%.When it comes to definite diagnosis,the coincidence rate is 72.5% of benign tumor while it is 28.7%of malignant tumor.And the coincidence rate of qualitative diagnosis is 99.0% of benign tumor when it is 52.2% of malignant tumor.The SE,SP,YI,PPV,NPV,LR+,and LR-for detecting parotid gland malignancy were 52.2%,99.0%,0.51,89.0%,93.0%,51.1,and 0.48 respectively.3.Compared between intraoperative FS diagnosis and postoperative histopathology of 340 patients,it showed that the coincidence rate of definite diagnosis was 97.8%,and of qualitative diagnosis was 83.1%.When it comes to definite diagnosis,the coincidence rate is 99.4% of benign tumor while it is 88.5% of malignant tumors.And the coincidence rate of qualitative diagnosis is 89.0% of benign tumor when it is 48.1% of malignant tumor.The SE,SP,YI,PPV,NPV,LR+,and LR-for detecting parotid gland malignancy were 90.4%,99.4%,0.90,95.9%,98.4%,139.6,and 0.097 respectively.4.After comparing 317 patients who accepted both FNAC and FS,we realized that the qualitative diagnostic value of FS was higher than that of FNAC(P<0.001).The data of patients with benign tumor were not statistically significant(P=1.000)while the data of patients with malignant tumor is statistically significant(P<0.001).Conclusion:1.The results of FNAC can be applied to a preoperative reference to identity parotid gland tumor initially.FNAC are more reliable when the results are malignant,but false negative results should be vigilant when the results are benign.We should not regard FNAC as a only diagnostic basis for parotid tumor or use it to determine the specific histopathological type of parotid tumor.A good way we can do is to optimize its operation and reporting procedures and combine with other technical means to improve its accuracy in clinical practice.2.The diagnostic coincidence rate of parotid gland tumor of FS is high than it of FNAC.The missed diagnosis rate of FS is lower as well.Thus,FS are suitable to be routinely used in parotid gland tumor surgery.